Route Of Absorption Research Articles

Phenotypic Changes of Trichinella Spiralis Treated By Commiphora Molmol,Lepidium Sativum, and Albendazole: in Vitro Study.

SummaryTrichinellosis is a nematode-causing disease distinguished by its continuous transmission in the carnivores and omnivores. Despite effective eradication of the enteral forms, conventional drugs fail to eliminate the migrating and muscle ones. Over the past years, researchers intensified the work on herbal medicines as alternatives or aids to albendazole, the reference drug. This research hypothesizes that the therapeutic agent absorption route could be an evidence-based carrier molecule or auxiliary drug to albendazole. Accordingly, this in vitro study was designed to investigate mainly the phenotypic changes induced by a mono-treatment of albendazole, Lipidium sativum (garden cress), and Commiphora molmol (myrrh). Incredibly, no data were reported on the morphological alterations of T. spiralis larvae treated by any of these drugs. The experimental design tested various concentrations (25, 50, 100, and 200 μg/ml) of each herbal medicine for the lethal effects on the parasite forms for a day (1, 12, and 24h). The data showed that the highest significant mortality rate of the parasite forms was in favor of the concentration 200 μg/ml of both plant extracts in a time-dependent manner. Therefore, albendazole at 200 μg/ml dose was tested in parallel, and all experimental groups were compared to non-treated muscle larvae and worms. Albendazole-treated worms accounted for the least significant (p<0.001) survival rate (2 %), followed by myrrh (5 %), and the adverse was valid for the survival rate of the muscle larvae at that time. None of the larvae/worms was alive after 24 hours of incubation with the 200μg/ml of either treatment. The scanning electron microscope investigation of the experimental groups provided a shred of evidence for different routes of taking up the candidate drugs by the parasite. In conclusion, the results of the previous work in vivo and current in vitro study recommend myrrh over garden cress as a complementary agent of albendazole.

A nationwide survey of 20 legacy brominated flame retardants in indoor dust from China: continuing occurrence, national distribution, and implication for human exposure.

Despite the restrictions on polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDDs), these chemicals are still ubiquitous environmental pollutants. In this study, we measured the concentrations and profiles of 17 PBDE congeners and 3 HBCDD isomers in indoor dust samples collected from 23 provinces and cities across China. The summed concentrations of PBDEs (Σ17PBDEs) ranged from 4.19 to 817ng/g, with an average of 171 ± 184ng/g. BDE-209 was the most abundant congener. The concentrations of HBCDDs ranged from 6.65 to 1335ng/g, with an average of 236 ± 324ng/g. Unlike commercial HBCDD formulations, α-HBCDD was the predominant isomer in the indoor dust samples analyzed. Geographical distributions showed that the concentrations of PBDEs and HBCDDs varied significantly among different regions. Higher PBDE and HBCDD levels were observed in samples from eastern coastal and economically developed regions. Further, we estimated the daily intakes of PBDEs and HBCDDs through the routes of dust ingestion and dust dermal absorption for different age groups. Dust dermal absorption is an unneglectable exposure pathway to PBDEs and HBCDs for the Chinese population. Among the age groups, infants had the highest exposure via dust dermal absorption, and toddlers had the highest exposure via dust ingestion. Compared with the threshold values, the exposure doses of PBDEs and HBCDDs are unlikely to pose significant health concerns for both infants and adults in China. This is the first national survey of PBDEs and HBCDDs in indoor dust samples across China after the restriction.

Effect of Massage with Oil Balanced in Essential Fatty Acids on Development and Lipid Parameters in Very Premature Neonates: A Randomized, Controlled Study.

Background: Oil massage versus only massage can increase preterm newborn development, especially weight gain, via a supposed percutaneous absorption of oil lipids, but data are contradictory. Aims: Investigating whether massage with a vegetable oil balanced in essential fatty acids improves neonatal weight gain, and digestive autonomy as proxy for neuro-development outcomes. Methods: A prospective monocentric randomized study was conducted in very premature newborns who received massage with oil (isio4 10 mL/kg/day, n = 18) versus with no oil (n = 18) for five consecutive days (10-min session twice daily) at a corrected gestational age of 34–35 weeks. Anthropometrics and clinical characteristics were recorded. Plasma triglyceride and total cholesterol concentrations were analyzed with an enzymatic kit. The fatty acid composition (weight%, mg/mL) of total plasma lipids and of red blood cell (RBC) membrane was analyzed by gas chromatography. Results: Weight gain velocity at the end of massage period was 12.3 ± 1.4 g/kg/day with oil vs. 9.8 ± 1.4 g/kg/day with no oil (p = 0.1). Digestive autonomy, plasma lipid parameters, polyunsaturated fatty acids in plasma total lipids or in RBC were comparable. The no oil group displayed a higher RBC level in nervonic acid at discharge (4.3 ± 0.2 vs. 3.4 ± 0.2%; p = 0.025) and in C18:1n-9 plasmalogen species at the end of the massage period and at discharge (0.73 ± 0.06 vs. 0.48 ± 0.06; 0.92 ± 0.06 vs. 0.69 ± 0.06%; p < 0.01), two molecules that are involved in neurodevelopment. Conclusions: The use of isio4 oil did not provide additional benefits for the development of very premature newborns, neither changed lipid metabolism nor polyunsaturated fatty acid biological status, which did not corroborate the existence of a percutaneous route for oil lipid absorption. The reason for different levels of nervonic acid and plasmalogen in RBC remains to be explored.

Effects of Cadmium Exposure on Gut Villi in Danio rerio.

In aquatic organisms, cadmium exposure occurs from ovum to death and the route of absorption is particularly wide, being represented by skin, gills and gastrointestinal tract, through which contaminated water and/or preys are ingested. It is known that cadmium interferes with the gut; however, less information is available on cadmium effects on an important component of the gut, namely goblet cells, specialized in mucus synthesis. In the present work, we studied the effects of two sublethal cadmium concentrations on the gut mucosa of Danio rerio. Particular attention was paid to changes in the distribution of glycan residues, and in metallothionein expression in intestinal cells. The results show that cadmium interferes with gut mucosa and goblet cells features. The effects are dose- and site-dependent, the anterior gut being more markedly affected than the midgut. Cadmium modifies the presence and/or distribution of glycans in the brush border and cytoplasm of enterocytes and in the goblet cells’ cytoplasm and alters the metallothionein expression and localization. The results suggest a significant interference of cadmium with mucosal efficiency, representing a health risk for the organism in direct contact with contamination and indirectly for the trophic chain.

Tailoring microstructures in (Ni/NiO)@C composites via facile route for broadband microwave absorption

The pollution of microwave radiation has gradually become a serious problem at the current stage. In the accepted method of material absorption, the rational regulation of electromagnetic parameters in composites via adjustment of their microstructures is an effective strategy to enhance their microwave absorbing ability. Herein, a kind of (Ni/NiO)@C composite with radial structure was obtained by co-hydrothermal and annealing method. The results show that the microstructure of composite could be regulated by adjusting the additional content of PTA, thus the commendable interface and dipole polarization, eddy current and exchange resonance loss, multiple reflection and scattering loss can be gathered together to absorb incident microwave. The optimal effective absorption bandwidth of as-prepared composite can reach an ultra-wide frequency range of 9.07 GHz for a great application at the thickness of only 1.79 mm, although the maximal reflected loss is −18.45 dB at 14.58 GHz for 1.5 mm thickness. The work reported here provides a facile route to modulate the self-organizing microstructure in composite and realize the wider band of microwave absorption.

Noninvasive Drug Delivery System Progress in Protein and Peptide Delivery

Protein and peptide drugs have tremendous therapeutic potential, and their usage in the treatment of various severe diseases has revolutionized the fields of pharmaceuticals and biotechnology. For successful therapeutic effects, several efforts have been made to deliver protein/peptide drugs through various routes of administration. Parenteral and nonparenteral drug deliveries are regarded as significant routes of drug absorption. However, there is a need to improve nonparenteral drug delivery systems (DDSs) through subsequent routes, including buccal, pulmonary, oral, ocular, transdermal, and nasal routes to increase drug absorption effectively. The study evaluated various DDS routes proposed for the distribution of proteins and peptides in terms of both parenteral and nonparenteral delivery systems. For this purpose, numerous research articles were searched from the year 2000 to 2021 using search engines such as PubMed, Google Scholar, Medline, ISI Web of Knowledge, and Bioline International while applying different keywords such as “protein and peptide drugs,” “drug delivery systems,” “parenteral and nonparenteral routes of drug delivery,” and “physicochemical barriers.” The invasive/parenteral routes have several limitations associated with drug delivery, such as poor patient compliance and the pain and discomfort associated with these routes inconvenience in treating the pediatric population. The oral route is one of the most convenient routes of noninvasive or nonparenteral drug administration; here, no pain and discomfort arise, thus helping in maintaining higher patient compliance or acceptance. The other routes of administration of proteins and peptides through buccal, intranasal, pulmonary, transdermal, rectal, and ocular routes have also been showing successful results. The success of the therapeutics is strongly influenced by the differential delivery of the targeted antigen, the choice of targeting protein or peptide, and the drug-release characteristics of the linker used. Furthermore, there should be an improvement in nonparenteral DDSs so that the drugs might be administered appropriately.

Environmental Hazards of Heavy Metal Pollution and Toxicity: A Review

Metals and especially heavy metals are one of the major constituents of environmental pollution. The sources of heavy metal pollution can be geogenic or anthropogenic. The man-made sources include fumes, metal laden dust or food components. Although, many metals are essential for animal metabolism but a dose exceeding the required concentration is often deleterious. The hazardous nature of these heavy metals has been extensively studied in human, animal and plants showing various toxicological impacts of toxic metals. The acute or chronic exposure of heavy metals to animals and human can result in severe injury to the structure and function of vital organs as liver, kidney, brain along with systemic disease conditions. The growth of plants is also severely affected by the intake of metallic compounds through the mineral and water absorption route. The deleterious effects on plants range from symptoms of injury to metabolic, enzymatic, and growth inhibition. The study of heavy metal pollution and the subsequent impact to flora and fauna can contribute in spreading public awareness and sensitizing policy makers to develop strategic planning in order to reduce the pollution and implement biological protection strategies.

Polymeric and electrospun patches for drug delivery through buccal route: Formulation and biointerface evaluation

IntroductionOf the various transmucosal routes which are being considered for extended and controlled drug delivery, buccal route is superior to other methods owing to high administrability and milder environment for drug absorption. In this direction, mucoadhesive buccal films of venlafaxine were fabricated using a combination of biocompatible polymers. AimThe main objective of the study was to standardize an optimized formulation of polyvinyl alcohol, sodium carboxymethyl cellulose and sodium alginate that would lead to sustained drug delivery in the form of buccal patches. MethodsVarying polymeric concentrations were utilized for the fabrication of buccal patches via solvent casting method. The physical parameters were evaluated, followed by in vitro drug release studies. The electrospun nanofibers were prepared for optimized formulations and the buccal delivery system was compared to oral and intravenous routes for absorption, distribution, and elimination during in vivo studies using venlaflaxine. ResultsThe patches had high tensile strength with uniform drug content and surface pH in the range of 6.28–6.88. The release of drug was steady witha maximum release of 89.97% at 5 h. The negative hemolytic and cytotoxicity studies with TR146 cells over a range of concentrations indicated biocompatibility of the mucoadhesive patch with human tissues. The pharmacokinetics of the buccal patch of the radiolabeled drug, 99mTc-venlaflaxine, displayed favorable release pattern. The radiolabeled patch attached to rabbit buccal mucosa displayed high retention with controlled drug release as indicated by the Cmax and T1/2 values (19.94 ng/ml and 3 h). The drug release mechanism corresponded to a pure fickian diffusion-controlled mechanism following Higuchi's model. Electrospun fibrous patch of the drug had a 10% higher drug release than solvent cast patch. ConclusionIn vitro and in vivo data indicate that the polymeric system was successfully optimized for sustained drug release for about 5 h in a continuous manner with electrospun fibrous patch showing 10% increase in drug release studies. The patches displayed ideal physical and biocompatibility characteristics. This polymeric combination can therefore be further utilized for development of novel drug delivery systems with sustained drug release pattern.

In vitro stability and ex vivo absorption of thymol monoglucosides in the porcine gut

Thymol α-D-glucopyranoside (TαG) and thymol β-D-glucopyranoside (TβG) are believed to have different kinetic behaviours in the porcine gut than its parent aglycon thymol. However, recently, it was shown that concentrations of both glucosides decreased rapidly in the stomach and proximal small intestine following oral supplementation to piglets as did thymol. Yet, the stability of thymol glucosides in gut contents and their absorption route remains obscure. Therefore, a series of in vitro incubations were performed, simulating the impact of pH, digestive enzymes, bacterial activity and mucosal extracts on stability of these glucosides. Their absorption mechanisms were investigated using the Ussing chamber model in the presence or the absence of inhibitors of sodium-dependent glucose linked transporter 1 and lactase phlorizin hydrolase. Both glucosides remained intact at physiological pH levels in the presence of digestive enzymes. Recoveries from TαG and TβG were below 90% when incubated with small intestinal homogenates from the distal jejunum or from all sampled sites, respectively. However, no aglycon could be detected in these samples. Bacterial inoculum of the small intestine, on the other hand, hydrolysed TβG quickly with up to 44% of free aglycon appearing. TαG proved more resistant to porcine gastro-intestinal bacterial glucosidases with only trace amounts (<1%) of free thymol at the end of the incubations. Electrophysiological measurements in Ussing chambers did not suggest active transport of the glucosides. Mucosal TαG and TβG concentrations were unchanged between start and end of the absorption measurements. Additionally, no TαG and only a very limited amount of TβG were retrieved from the serosal side. Tissue associated concentrations, although marginal (<1% of luminal concentration), were mainly as intact glucoside or as aglycon for TαG and TβG, respectively. Addition of both inhibitors significantly increased the amount of intact glucosides retrieved from the mucosal tissues as compared to controls. In conclusion, bacterial hydrolysis was identified as the most important source of TβG loss, whereas TαG seemed less prone to degradation or absorption in these in vitro and ex vivo models.

Exposure of Caenorhabditis elegans to Dietary Nε-Carboxymethyllysine Emphasizes Endocytosis as a New Route for Intestinal Absorption of Advanced Glycation End Products.

The impact of dietary advanced glycation end products (dAGEs) on human health has been discussed in many studies but, to date, no consensual pathophysiological process has been demonstrated. The intestinal absorption pathways which have so far been described for dAGEs, the passive diffusion of free AGE adducts and transport of glycated di-tripeptides by the peptide transporter 1 (PEPT-1), are not compatible with certain pathophysiological processes described. To get new insight into the intestinal absorption pathways and the pathophysiological mechanisms of dAGEs, we initiated an in vivo study with a so-called simple animal model with a complete digestive tract, Caenorhabditis elegans. Dietary bacteria were chemically modified with glyoxylic acid to mainly produce Nε-carboxymethyllysine (CML) and used to feed the worms. We performed different immunotechniques using an anti-CML antibody for the relative quantification of ingested CML and localization of this AGE in the worms’ intestine. The relative expression of genes encoding different biological processes such as response to stresses and intestinal digestion were determined. The physiological development of the worms was verified. All the results were compared with those obtained with the control bacteria. The results revealed a new route for the intestinal absorption of dietary CML (dCML), endocytosis, which could be mediated by scavenger receptors. The exposure of worms to dCML induced a reproductive defect and a transcriptional response reflecting oxidative, carbonyl and protein folding stresses. These data, in particular the demonstration of endocytosis of dCML by enterocytes, open up new perspectives to better characterize the pathophysiological mechanisms of dAGEs.

Posterior Segment Ophthalmic Drug Delivery: Role of Muco-Adhesion with a Special Focus on Chitosan.

Posterior segment eye diseases (PSEDs) including age macular degeneration (AMD) and diabetic retinopathy (DR) are amongst the major causes of irreversible blindness worldwide. Due to the numerous barriers encountered, highly invasive intravitreal (IVT) injections represent the primary route to deliver drugs to the posterior eye tissues. Thus, the potential of a more patient friendly topical route has been widely investigated. Mucoadhesive formulations can decrease precorneal clearance while prolonging precorneal residence. Thus, they are expected to enhance the chances of adherence to corneal and conjunctival surfaces and as such, enable increased delivery to the posterior eye segment. Among the mucoadhesive polymers available, chitosan is the most widely explored due to its outstanding mucoadhesive characteristics. In this review, the major PSEDs, their treatments, barriers to topical delivery, and routes of topical drug absorption to the posterior eye are presented. To enable the successful design of mucoadhesive ophthalmic drug delivery systems (DDSs), an overview of mucoadhesion, its theory, characterization, and considerations for ocular mucoadhesion is given. Furthermore, chitosan-based DDs that have been explored to promote topical drug delivery to the posterior eye segment are reviewed. Finally, challenges of successful preclinical to clinical translation of these DDSs for posterior eye drug delivery are discussed.

Sophistication in a seemingly simple creature: a review of wild holothurian nutrition in marine ecosystems.

ABSTRACTHolothurians are marine invertebrates that are among the most widespread benthic megafauna communities by both biomass and abundance in shallow‐water and deep‐sea ecosystems, their functions supporting important ecological services worldwide. Despite their simple appearance as sea cucumbers, holothurians show a wide range of feeding practices. However, information on what and how these animals eat is scattered and potentially confusing. We provide a comprehensive review of holothurian nutrition in coastal and deep‐sea ecosystems. First, we describe morphological aspects of holothurian feeding and the ultrastructure of tentacles. We discuss the two processes for food capture, concluding that mucus adhesion is likely the main method; two mucous cells, type‐1 and type‐2, possibly allow the adhesion and de‐adhesion, respectively, of food particles. Secondly, this review aims to clarify behavioural aspects of holothurian suspension‐ and deposit‐feeding. We discuss the daily feeding cycle, and selective feeding strategies. We conclude that there is selectivity for fine and organically rich particles, and that feeding through the cloaca is also a route for nutrient absorption. Third, we provide a wide description of the diet of holothurians, which can be split into two categories: living and non‐living material. We suggest that Synallactida, Molpadida, Persiculida, Holothuriida and Elasipodida, ingest the same fractions, and emphasise the importance of bacteria in the diet of holothurians.

Trace minerals for improved performance: a review of Zn and Cu supplementation effects on male reproduction in goats.

Minerals are required in small amounts but play significant roles in many physiological functions related with growth, reproduction, and health of goats such as biochemical, molecular systems, and optimized enzymatic activities due to their roles as co-factors to metalloenzymes. Among them, zinc (Zn) and copper (Cu) are leading essential elements in goat nutrition, because of their role across several biological functions. The proportion of these minerals availability and absorption from the ingested feed is usually less, because of their complexities with un-degradable parts of feed resources. Hence, their exogenous supplementation is required for normal animal functions. On this background, this review presents findings associated with supplementation of these minerals in organic form as a way for improving the fertility of male goats with special focus on physico-chemical-kinetics of the semen for improving the application of reproductive technologies. This review emphasizes the organic sources of these minerals to replace the inorganic sources, based on their significance in improving semen qualities, antioxidant protection, and mediation of molecular activities. This review also discusses salient routes of Zn and Cu absorption and identifies the need for molecular exploration for positive outcomes with supplementation of these minerals as an area of the future goat nutrition-reproduction improvement strategy.

Growth Hormone Overexpression Induces Hyperphagia and Intestinal Morphophysiological Adaptations to Improve Nutrient Uptake in Zebrafish.

The excess of circulating growth hormone (GH) in most transgenic animals implies mandatory growth resulting in higher metabolic demand. Considering that the intestine is the main organ responsible for the digestion, absorption, and direction of dietary nutrients to other tissues, this study aimed to investigate the mechanisms by which gh overexpression modulates the intestine to support higher growth. For this purpose, we designed an 8-weeks feeding trial to evaluate growth parameters, feed intake, and intestinal morphometric indices in the adult gh-transgenic zebrafish (Danio rerio) model. To access the sensitivity of the intestine to the excess of circulating GH, the messenger RNA (mRNA) expression of intestine GH receptors (GHRs) (ghra and ghrb) was analyzed. In addition, the expression of insulin-like growth factor 1a (igf1a) and genes encoding for di and tripeptide transporters (pept1a and pept1b) were assessed. Gh-transgenic zebrafish had better growth performance and higher feed intake compared to non-transgenic sibling controls. Chronic excess of GH upregulates the expression of its cognate receptor (ghrb) and the main growth factor related to trophic effects in the intestine (igf1a). Moreover, transgenic zebrafish showed an increased intestinal absorptive area and higher expression of crucial genes related to the absorption of products from meal protein degradation. These results reinforce the ability of GH to modulate intestinal morphology and the mechanisms of assimilation of nutrients to sustain the energy demand for the continuous growth induced by the excess of circulating GH.

Oral administration of cyanocobalamin for functional vitamin В&lt;sub&gt;12&lt;/sub&gt; deficiency: efficacy and safety

The prevalence of vitamin В12deficiency is about 3—16% in the general population, while in older people, it ranges from 10 to 20%. An increase in the proportion of people on reduced-calorie diets, the widespread use of drugs that can result in vitamin В12deficiency, an increase in life expectancy, on the one hand, a variety of clinical manifestations and the lack of precise algorithms for laboratory diagnostics, on the other hand, suggest that the number of patients with vitamin В12deficiency is significantly higher. Vitamin В12can be absorbed by passive diffusion, regardless of intrinsic factor and other underlying causes of the deficiency. The presence of an additional route of absorption brings in new expectations for the oral administration of cyanocobalamin in therapeutic doses. Comparative clinical trials of the use of cyanocobalamin have shown that the oral route of administration is as effective as the parenteral. Considering the need for long-term, and in some cases — life-long, use of the drug, there is a need to develop dosage regimens for oral administration comparable in effectiveness to parenteral administration. The use of functional vitamin В12deficiency biomarkers, such as vitamin В12levels, cholotranscobalamin, methylmalonic acid, homocysteine, made it possible to establish that a daily dose of 1000 mkg is the most effective, which at the initial stage is as efficient as intramuscular administration. In some circumstances, maintenance therapy (intramuscularly at a dose of 1 mg/month) was more effective; thus, a differentiated approach scheme to determining the maintenance oral dose was proposed, depending on the result obtained at the initial stage of therapy. Comparative studies covering the entire spectrum from the recommended dietary allowance to the dose commonly used for cobalamin injections have shown that an oral daily dose of 1000 mcg of cyanocobalamin normalizes serum vitamin В12levels and causes an 80—90% decrease in plasma methylmalonic acid concentration from the assumed maximum value. The oral route of administration provides a higher patient treatment adherence.

Increasing the Power of Polyphenols through Nanoencapsulation for Adjuvant Therapy against Cardiovascular Diseases

Polyphenols play a therapeutic role in vascular diseases, acting in inherent illness-associate conditions such as inflammation, diabetes, dyslipidemia, hypertension, and oxidative stress, as demonstrated by clinical trials and epidemiological surveys. The main polyphenol cardioprotective mechanisms rely on increased nitric oxide, decreased asymmetric dimethylarginine levels, upregulation of genes encoding antioxidant enzymes via the Nrf2-ARE pathway and anti-inflammatory action through the redox-sensitive transcription factor NF-κB and PPAR-γ receptor. However, poor polyphenol bioavailability and extensive metabolization restrict their applicability. Polyphenols carried by nanoparticles circumvent these limitations providing controlled release and better solubility, chemical protection, and target achievement. Nano-encapsulate polyphenols loaded in food grade polymers and lipids appear to be safe, gaining resistance in the enteric route for intestinal absorption, in which the mucoadhesiveness ensures their increased uptake, achieving high systemic levels in non-metabolized forms. Nano-capsules confer a gradual release to these compounds, as well as longer half-lives and cell and whole organism permanence, reinforcing their effectiveness, as demonstrated in pre-clinical trials, enabling their application as an adjuvant therapy against cardiovascular diseases. Polyphenol entrapment in nanoparticles should be encouraged in nutraceutical manufacturing for the fortification of foods and beverages. This study discusses pre-clinical trials evaluating how nano-encapsulate polyphenols following oral administration can aid in cardiovascular performance.

Calcium looping post-combustion CO2 capture in sugarcane bagasse fuelled power plants

Biomass energy conversion with carbon capture and storage (BECCS) can lead to the net removal of CO2 from the atmosphere. Calcium looping (CaL) is a promising carbon capture process for existing or greenfield capture-ready biomass-fired plants. This paper investigates the technical and economic performance of BECCS using CaL systems as a retrofit to Brazilian cogeneration plants fuelled with sugarcane bagasse. Bagasse-fired cogeneration plants integrated with CaL were compared with their correspondent base plant without CO2 capture and with chemical absorption using Cansolv solvent, the current benchmark for post-combustion CO2 capture. Key parameters such as CO2 removal potential, water use, added plant footprint, and levelized energy cost (LCOE) were analyzed. Although the Bio-CaL alternative is not cost-effective compared to Cansolv for a first of a kind plant, the assessed system presents competitive advantages in operational flexibility, energy efficiency, and electricity surplus in comparison with the chemical absorption route. For future plants, economic results are promising and can match those of more conventional technologies. Therefore, investments in pilot size biomass-fired CaL units should be stimulated to promote learning and allow the implementation of large-scale plants that would likely operate with similar costs but greater flexibility and thermal efficiency than the current more mature CO2 capture technologies.

A wide-angle broadband electromagnetic absorbing metastructure using 3D printing technology

Gradient composite metastructures have been demonstrated in effectively improving the microwave absorbing performance. However, the preparation of the complex structures still remains challenging. Herein, a complex gradient composite microwave absorbing metastructure is designed and fabricated by the low cost, high-efficiency fused deposition modeling of 3D printing technologies. The metastructure is composed of flaky carbonyl iron particles and Polyether-ether-ketone composite which demands only 50% loss material mass addition. Structural parameters are investigated and optimized for absorbing bandwidth and reflectivity intensity. Simulations and experiments demonstrate that the designed complex gradient metastructure with the thickness of 10 mm can achieve the −10 dB absorbing bandwidth in the frequency range from 5.1 to 40 GHz, and the absorbing bandwidth corresponding to −15 dB in 7.7–14.7 GHz and 22.6–36.3 GHz. Meanwhile, this metastructure also can maintain the broadband and strong microwave absorption with incident angle from 0° to 55° for transverse electric polarization and 0° to 70° for transverse magnetic polarization. Moreover, the proposed metastructure is also demonstrated with good compression strength which shows preferable mechanical stability. This work provides a simple and promising route of broadband and wide-angle microwave strong absorption for practical application.

Magnetic resonance imaging analysis of human skull diploic venous anatomy.

Background: The skull diploic venous space (DVS) represents a potential route for cerebrospinal fluid (CSF) diversion and absorption in the treatment of hydrocephalus. The goal of this study was to carry out a detailed characterization of the drainage pattern of the DVS of the skull using high-resolution MRI, especially the diploic veins draining to the lacunae laterales (LLs) since the LLs constitute an important channel for the CSF to access the superior sagittal sinus and subsequently the systemic circulation. The objective was to identify those skull regions optimally suited for an intraosseous CSF diversion system.Methods: High-resolution, T1-weighted MRI scans from 20 adult and 16 pediatric subjects were selected for analysis. Skulls were divided into four regions, that is, frontal, parietal, temporal, and occipital. On each scan, a trained observer counted all diploic veins in every skull region. Each diploic vein was also followed to determine its final drainage pathway (i.e., dural venous sinus, dural vein, LL, or indeterminate).Results: In the adult age group, the frontal and occipital skull regions showed the highest number of diploic veins. However, the highest number of draining diploic veins connecting to the lacunae lateralis was found in the frontal and parietal skull region, just anterior and just posterior to the coronal suture. In the pediatric age group, the parietal skull region, just posterior to the coronal suture, showed the highest overall number of diploic veins and also the highest number of draining diploic veins connecting to the LL.Conclusion: This study suggested that diploic venous density across the skull varies with age, with more parietal diploic veins in the pediatric age range, and more occipital and frontal diploic veins in adults. If the DVS is ultimately used for CSF diversion, our anatomical data point to optimal sites for the insertion of specially designed intraosseous infusion devices for the treatment of hydrocephalus. Likely the optimal sites for CSF diversion would be the parietal region just posterior to the coronal suture in children, and in adults, frontal and/or parietal just anterior or just posterior to the coronal suture.

Spatio-temporal assessment, sources and health risks of water pollutants at trace levels in public supply river using multivariate statistical techniques

The Joanes River is located in the northeast of Brazil, crosses the Camaçari Petrochemical Complex, the largest integrated industrial complex in the Southern Hemisphere, which has over 90 companies in the chemical and petrochemical industry. The present study aims to evaluate spatial distribution, seasonal variation and identify possible sources of trace metal contamination in surface water samples of the Joanes River. Samples were collected in the dry (December 2018) and rainy (August 2019) seasons. Analysis of trace elements (As, Cd, Cr, Cu, Ni, Mn and Pb) were performed by ICP-MS. A total of 60 water samples were obtained. Samples were analyzed using exploratory techniques such as principal component analysis (PCA) and cluster analysis (CA). It was possible to characterize the samples according to the seasonal variation. The formation of two groups was observed. Among these, samples from the rainy season presented the higher levels of metals in relation to the samples of the dry season. Natural and anthropic sources of metal contamination were identified using CA. Similarity was shown in the relationship between the metals As–Pb and Ni–Cd–Cr–Cu in the dry season, and Cd–Ni and Pb–As–Cr–Cu in the rainy season. Dermal absorption (HQderm) and ingestion hazard quotients (HQing) routes exhibited values of less than one for all the elements analyzed for adults and children, in both rainy and dry seasons. This indicated that the pollutants analyzed posed little or no health risk over a lifetime of exposure. According to international guidelines (US EPA), the values of Cu, Pb and Cr were above the limit established.