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Pest Management Science Jun 2024Over the past two decades, bed bugs (Cimex spp.) have resurged as common urban pests around the world. The search for efficient and safe control measures has become a...
BACKGROUND
Over the past two decades, bed bugs (Cimex spp.) have resurged as common urban pests around the world. The search for efficient and safe control measures has become a key interest among researchers, manufacturers, and pest control professionals. In this study, we evaluated and compared the efficacy of steam, diatomaceous earth (DE) dust, and a combination of both against tropical bed bugs (Cimex hemipterus (F.)) under laboratory and field conditions.
RESULTS
In the laboratory study, the mortality of bed bugs after 2 days of exposure to DE dust was 100%. When bed bugs stayed on the surface of an object or in cracks, a brief steam treatment (1 s) caused 100% mortality. However, when bed bugs were hidden under a fabric cover, steam application for 10 s only caused 89 ± 6% mortality. Bed bugs that survived steam treatment exhibited reduced feeding activity. In a 14-week long study, there was no significant difference in the reduction rate of bed bugs between steam treatment and DE dust treatment. A 37-week long control study showed that steam and steam plus DE dust treatments eliminated 97-100% of the infestations.
CONCLUSION
Applying steam and DE dust are effective strategies for eliminating natural tropical bed bug infestations. Continuous follow-up monitoring and treatment until no bed bugs are found are crucial in completely eliminating the infestation of tropical bed bugs. © 2024 Society of Chemical Industry.
PubMed: 38847149
DOI: 10.1002/ps.8227 -
Journal of the Mechanical Behavior of... Sep 2022The effect of a natural filler (diatomaceous earth [DE], a promising drug-delivery agent) and its content was investigated on the performance of a model glass-ionomer...
The effect of a natural filler (diatomaceous earth [DE], a promising drug-delivery agent) and its content was investigated on the performance of a model glass-ionomer cement (GIC). Three sample series, differing in DE content (0, 2.5 and 5 wt%), were prepared using a commercial GIC as a matrix (3M Ketac Molar Easymix). The resultant surface microhardness and roughness, wear performance, and compressive strength of the samples were measured after the samples had been stored in deionized water at 37°C for a fixed time. Moreover, the film thickness was tested for the freshly mixed samples. The numerical data was subjected to statistical analysis, in order to test the null hypotheses of the equality of the measured properties between the reference and the DE-modified samples. According to the results, diatomaceous earth particles are uniformly distributed in the GIC matrix, and the cavities of frustules tend to be filled with the GIC. This translates into the observed performance of the DE-loaded GIC. Compared with the reference material (0 wt% DE), the surface microhardness (2.5 wt% DE, p = 0.014; 5 wt% DE, p = 0.005) and roughness (e.g. Ra; 2.5 wt% DE, p = 0.003; 5 wt% DE, p < 0.001) are increased. No effect on the wear performance (p = 0.530 and 0.256, respectively) or compressive strength (p = 0.514) was noticed in the case of DE partially substituting the glass phase. Based on the study results, it is evidenced that diatom frustules are a suitable filler for application in conventional glass-ionomer cements as the glass-substituting drug-loaded carrier. Notably, however, the surface finish method of the DE-filled materials needs development.
Topics: Compressive Strength; Diatomaceous Earth; Drug Carriers; Glass Ionomer Cements; Materials Testing
PubMed: 35738132
DOI: 10.1016/j.jmbbm.2022.105324 -
Molecules (Basel, Switzerland) Dec 2023Heparin, a highly sulfated glycosaminoglycan, is a naturally occurring anticoagulant that plays a vital role in various physiological processes. The remarkable...
Heparin, a highly sulfated glycosaminoglycan, is a naturally occurring anticoagulant that plays a vital role in various physiological processes. The remarkable structural complexity of heparin, consisting of repeating disaccharide units, makes it a crucial molecule for the development of commercial drugs in the pharmaceutical industry. Over the past few decades, significant progress has been made in the development of cost-effective adsorbents specifically designed for the adsorption of heparin from porcine intestinal mucosa. This advancement has been driven by the need for efficient and scalable methods to extract heparin from natural sources. In this study, we investigated the use of cationic ammonium-functionalized diatomaceous earth, featuring enhanced porosity, larger surface area, and higher thermal stability, to maximize the isolated heparin recovery. Our results showed that the higher cationic density and less bulky quaternary modified diatomaceous earth (QDADE) could adsorb up to 16.3 mg·g (31%) of heparin from the real mucosa samples. Additionally, we explored the conditions of the adsorbent surface for recovery of the heparin molecule and optimized various factors, such as temperature and pH, to optimize the heparin uptake. This is the introductory account of the implementation of modified diatomaceous earth with quaternary amines for heparin capture.
Topics: Animals; Swine; Diatomaceous Earth; Heparin; Anticoagulants; Temperature; Intestinal Mucosa
PubMed: 38138471
DOI: 10.3390/molecules28247982 -
International Journal of Molecular... Aug 2022A neoteric round sieve diatomite (De) decorated with sea-urchin-like alpha-type iron trioxide (α-FeO) synthetics was prepared by the hydrothermal method and further...
A neoteric round sieve diatomite (De) decorated with sea-urchin-like alpha-type iron trioxide (α-FeO) synthetics was prepared by the hydrothermal method and further calcination. The results of the electromagnetic (EM) parameters of α-FeO-decorated De (α-FeO@D) showed that the minimum reflection loss (RL) of α-FeO@D could reach -54.2 dB at 11.52 GHz and the matched absorber thickness was 3 mm. The frequency bandwidth corresponding to the microwave RL value below -20 dB was up to 8.24 GHz (9.76-18 GHz). This indicates that α-FeO@D composite can be a lightweight and stable material; because of the low density of De (1.9-2.3 g/cm), the density of α-FeO@D composite material is lower than that of α-FeO (5.18 g/cm). We found that the combination of the magnetic loss of sea-urchin-like α-FeO and the dielectric loss of De has the most dominant role in electromagnetic wave absorption and loss. We focused on comparing the absorbing properties before and after the formation of sea-urchin-like α-FeO and explain in detail the effects of the structure and crystal shape of this novel composite on the absorbing properties.
Topics: Diatomaceous Earth; Microwaves
PubMed: 36012621
DOI: 10.3390/ijms23169362 -
Materials (Basel, Switzerland) Feb 2022In this study, the potential use of waste diatomaceous earth from the production of diatomaceous earth for filtration purposes, as an alternative raw material for foam...
In this study, the potential use of waste diatomaceous earth from the production of diatomaceous earth for filtration purposes, as an alternative raw material for foam glass production, was explored. The chemical and mineralogical composition and the high temperature behavior of waste diatomite were studied to assess its suitability for foam glass production. Glass-ceramic foams were prepared using NaOH solution as a foaming agent, via a hydrate mechanism. The influence of different pretreatments and firing temperatures on the foam's structure, bulk density and compressive strength was investigated. High temperature behavior was studied using TG/DTA analysis and high temperature microscopy. Phase composition was studied using X-ray diffraction analysis. Glass-ceramic foam samples of a high porosity comparable to conventional foam glass products were fabricated. The pretreatment temperature, foaming temperature and sintering holding time were found to have a significant influence on foam properties. With increased pretreatment temperature, pyrogenic carbon from the thermal decomposition of organic matter contained in the raw material acted as an additional foaming agent and remained partially unoxidized in prepared foams. The bulk densities of prepared samples ranged from 150 kg/m to 510 kg/m and their compressive strengths were between 140 and 1270 kPa.
PubMed: 35207924
DOI: 10.3390/ma15041384 -
Molecules (Basel, Switzerland) Dec 2021Nowadays, we are tackling various issues related to the overuse of synthetic insecticides. Growing concerns about biodiversity, animal and human welfare, and food... (Review)
Review
Nowadays, we are tackling various issues related to the overuse of synthetic insecticides. Growing concerns about biodiversity, animal and human welfare, and food security are pushing agriculture toward a more sustainable approach, and research is moving in this direction, looking for environmentally friendly alternatives to be adopted in Integrated Pest Management (IPM) protocols. In this regard, inert dusts, especially diatomaceous earths (DEs), hold a significant promise to prevent and control a wide range of arthropod pests. DEs are a type of naturally occurring soft siliceous sedimentary rock, consisting of the fossilized exoskeleton of unicellular algae, which are called diatoms. Mainly adopted for the control of stored product pests, DEs have found also their use against some household insects living in a dry environment, such as bed bugs, or insects of agricultural interest. In this article, we reported a comprehensive review of the use of DEs against different arthropod pest taxa, such as Acarina, Blattodea, Coleoptera, Diptera, Hemiptera, Hymenoptera, Ixodida, Lepidoptera, when applied either alone or in combination with other techniques. The mechanisms of action of DEs, their real-world applications, and challenges related to their adoption in IPM programs are critically reported.
Topics: Animals; Arthropods; Diatomaceous Earth; Insect Control; Insecticides
PubMed: 34946567
DOI: 10.3390/molecules26247487 -
Biotechnology Advances Nov 2022Phospholipids are unique and versatile molecules, essential in a variety of biological systems. Moreover, their diverse structures and amphiphilic properties endorse... (Review)
Review
Phospholipids are unique and versatile molecules, essential in a variety of biological systems. Moreover, their diverse structures and amphiphilic properties endorse their indispensable and unparalleled roles in research and industrial-related applications. However, in most cases of applications, naturally occurring phospholipids are either deficit in structural variety or insufficient in quantity; therefore, novel methods must be developed for the synthesis of new molecules or modification of natural structures. To identify sustainable and environmentally friendly approaches, this work reviews the latest progress in the acquisition of structurally defined phospholipids (designer phospholipids) from natural resources, including structural retrieval, redesign and synthesis of designer phospholipids via chemo-/enzymatic approaches. This review additionally highlights the opportunity to use biological systems to direct the production of specific phospholipid species through genetic engineering via defined metabolic pathways, and functionalization of natural phospholipids through synthetic modifications: substitutions, removals or additions of specific functional groups. A particular focus is given to the establishment of chemical and biological systems for the synthesis of isotopically labelled phospholipids for biomedical applications. The application of green chemistry principles in semi-synthesis of phospholipids including extended use of greener biocatalysts and diatomaceous earth and reduced use of hazardous and toxic solvents is also summarized.
Topics: Diatomaceous Earth; Phospholipids; Solvents
PubMed: 35914627
DOI: 10.1016/j.biotechadv.2022.108025 -
Environmental Science and Pollution... Feb 2021In the present study, we evaluated the insecticidal efficacy of diatomaceous earth (DE) and pirimiphos-methyl for the control of phosphine-susceptible and...
In the present study, we evaluated the insecticidal efficacy of diatomaceous earth (DE) and pirimiphos-methyl for the control of phosphine-susceptible and phosphine-resistant populations of Tribolium castaneum (Herbst) and Sitophilus oryzae (L.). Insecticides were applied on wheat or rice at two doses: DE was applied at 1000 and 2000 ppm and pirimiphos-methyl at 1 and 5 ppm. Adult mortality was measured after 7, 14, and 21 days of exposure, and progeny production capacity on the treated substrates was evaluated 65 days later. For T. castaneum, we found that DE, at 2000 ppm, was able to provide 100% control of two of the three populations tested, while for the third population mortality reached only 84%. Similarly, there were differences in mortality levels after exposure to DE-treated grains between the two S. oryzae populations tested. At 1 ppm, pirimiphos-methyl was not effective for any of the T. castaneum populations tested, but complete mortality was recorded for all populations at 5 ppm. In general, populations of S. oryzae were more susceptible than those of T. castaneum, for both commodities. Our data indicate that both insecticides can be used with success in phosphine resistance management programs, but there are populations of a given species that may be less susceptible, which constitutes a preliminary screening essential.
PubMed: 33635464
DOI: 10.1007/s11356-021-12971-1 -
Journal of Food Protection Jan 2021Almonds rejected as inedible are often used for production of almond oil. However, low-quality almonds are frequently contaminated with aflatoxins, and little is known...
ABSTRACT
Almonds rejected as inedible are often used for production of almond oil. However, low-quality almonds are frequently contaminated with aflatoxins, and little is known regarding transfer of aflatoxins to almond oil during processing. In this study, oil was produced from reject almonds by hexane extraction. Of 19 almond samples that were naturally contaminated with aflatoxins, 17 oil samples contained measurable amounts of aflatoxins, and aflatoxin content of contaminated oil was correlated with aflatoxin content of the nuts. However, oil aflatoxin levels were not correlated with the oxidation level of the oil as measured by percent free fatty acids and peroxide value. Adsorbents used in oil refining were tested for their ability to remove aflatoxins from contaminated oil. Fuller's earth and bentonite were the most effective, removing 96 and 86% of total aflatoxins from contaminated oil samples, respectively. Treatment with diatomaceous earth, in contrast, had no effect on aflatoxin levels in oil. These results show that oil refining steps using mineral clay adsorbents may also function to remove aflatoxins from contaminated oil.
Topics: Aflatoxins; Nuts; Plant Oils; Prunus dulcis
PubMed: 32882027
DOI: 10.4315/JFP-20-229 -
Science & Justice : Journal of the... May 2023Environmental trace evidence offers useful circumstantial intelligence to link persons and scenes of forensic interest. An increasing empirical research base is...
Environmental trace evidence offers useful circumstantial intelligence to link persons and scenes of forensic interest. An increasing empirical research base is dedicated towards understanding the transfer and persistence dynamics of environmental indicators including pollen, soils, and diatoms, within a diverse range of experimental frameworks. This paper presents two discrete studies exploring transfer and persistence of soils and sediments on footwear and diatomaceous earth adhered to clothing in forensically pertinent scenarios. Variables including sediment type, foot position, clothing type, and body positioning were also explored throughout. Both experiments incorporated a field-based methodology during the sampling effort. Photographs were collected of an initial transfer sample and of a retained assemblage following hours, days, and up to one-week of wear, facilitating macroscopic assessment of trace evidence dynamics. All images were processed using accessible, open-source software before spatial analysis of evidence distribution within and temporal assessment (% retention) upon each evidential surface. The results highlighted consistent loss of transferred sediment from footwear with significantly greater retention of loamy clay soil than dune sand which was absent beyond 24 h of wear. Loss was not influenced by wearer gait but was more rapid from those areas of the shoe sole in direct contact with the ground. Diatomaceous earth was retrieved from all three clothing types tested after one week - significant losses of material occurred before 48 h with a consistent assemblage identified beyond this. Denim was significantly more effective than acrylic and fleece for diatomaceous earth retention and significantly more material was lost from clothing worn on the lower body. These findings highlight the value of using visual environmental markers and a macroscopic analytical approach during the investigation of environmental trace dynamics. The methodology offers a novel, non-destructive assessment of soil and diatom transfer and persistence, complementing more extensive laboratory-based examinations to ensure the development of a well-rounded research base within the forensic sciences.
Topics: Humans; Clothing; Diatomaceous Earth; Forensic Medicine; Shoes; Forensic Sciences; Soil
PubMed: 37169463
DOI: 10.1016/j.scijus.2023.03.004