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Marek's disease virus (MDV) integrates its genome into the telomeres of host chromosomes and causes fatal lymphomas in chickens. This integration is facilitated by telomeric repeat sequences (TMRs) at the ends of the viral genome, and is crucial for MDV-induced lymphomagenesis. The SB-1 vaccine virus is commonly used in commercial bivalent vaccines against MDV and also contains TMRs at its ends. Here, we demonstrate that SB-1 efficiently integrates its genome into the chromosomes of latently infected T cells. Deletion of the TMRs from the SB-1 genome did not affect virus replication, but severely impaired virus integration and genome maintenance in latently infected T cells and in chickens. Strikingly, the reduced integration and maintenance of latent SB-1 significantly impaired vaccine protection. Taken together, our data revealed that the TMRs facilitate SB-1 integration and that integration and/or maintenance of the latent viral genome is critical for vaccine protection. [ABSTRACT FROM AUTHOR]

The adsorption of pollutants onto metal and metal oxide nanoparticles of zinc oxide, silver, magnetite, and copper oxide as efficient adsorbents has received tremendous attention in recent years. However, only a few reports are available on the adsorption potentials of NiO nanoparticles (NiONPs). This work reports the adsorption of amoxicillin and nortriptyline pharmaceuticals onto biosynthesized NiONPs prepared from the aqueous leave extract of Platanus occidentalis. The plant leaf-mediated NiONPs were characterized via standard techniques and revealed successful synthesis of the nano-adsorbent. The NiONPs showed a pHpzc of 8.6, a surface area of 128.4 m2/g, pore volume of 0.486 cm3/g, and a pore diameter of 12.84 nm. The adsorption capacity of NiONPs for amoxicillin and nortriptyline was 116.7 mg/g and 72.62 mg/g, respectively. The Freundlich model was well suited to the isotherm modeling of the process compared to Temkin and Langmuir models. Kinetics was well described by the pseudo-second-order and intraparticle diffusion rate equations. The adsorption was found to be exothermic and spontaneous with a decrease in randomness at the pharmaceutical NiONPs interface. The biosynthesized NiONPs showed less than 10% decrease in the percentage adsorption of both pollutants after five cycles of reuse. This research showed that Platanus occidentalis leaf-mediated NiONPs is an efficient material for the adsorption of amoxicillin and nortriptyline. [ABSTRACT FROM AUTHOR]

Bromophenol blue is a toxic triphenylmethane dye that is widely used in various industries. The dye-contaminated wastewater released from the industries results in substantial water pollution, causing several health problems and having severe negative consequences for the ecosystem. As a result, its toxic presence in environmental water is a cause for serious concern. Therefore, the removal of wastewater is vital to preserving environmental quality. The adsorption process stands out among several water treatment techniques due to its low cost, efficiency, simplicity, selectivity, and recyclability. Thus, several adsorbents have been applied for the treatment of bromophenol blue-contaminated water via the adsorption technique. This review presents the adsorption of bromophenol blue onto bio-based adsorbents such as biomass, activated carbon, and biochar as well as other potent materials like nanoparticles, polymers, and composite. The isotherm, kinetics, thermodynamics, and mechanism of the adsorption process were all discussed. We also considered the regeneration of the adsorbents and their reusability in the treatment process. Moreover, research gaps in many aspects were discovered, and future research proposals were offered. [ABSTRACT FROM AUTHOR]

Context: The solvation of metal ions is crucial to understanding relevant properties in physics, chemistry, or biology. Therefore, we present solvation enthalpies and solvation free energies of the ferrous ion in water and ammonia. Our results agree well with the experimental reports for the hydration free energy and hydration enthalpy. We obtained - 1888.7 kJ mol - 1 for the hydration free energy and - 1900.7 kJ mol - 1 for the hydration enthalpy of ferrous ion in water at room temperature. At ambient temperature, we obtained - 2065.7 kJ mol - 1 as the F e 2 + ammoniation free energy and - 2124.2 kJ mol - 1 for the ammoniation enthalpy. In addition, the free energy of solvation is deeply affected when the temperature increases. This pattern can be attributed to the rise of entropy when the temperature rises. Besides, the temperature does not affect the ammoniation enthalpies and the hydration enthalpy of the F e 2 + ion. Method: All the geometry optimizations are performed at the MP2 methods associated with the 6-31++g(d,p) basis set of Pople. solvated phase structures of F e 2 + ion in water or in ammonia are performed using the PCM model. The G a u s s i a n 16 program suite was used to perform all the calculations. The program TEMPO was also used to evaluate the temperature sensitivity of the different obtained geometries. [ABSTRACT FROM AUTHOR]

Many recent AI policies have been structured under labels that follow a particular trend: national or international guidelines, policies or regulations, such as the EU’s and USA’s ‘Trustworthy AI’ and China’s and India’s adoption of ‘Responsible AI’, use a label that follows the recipe of [agentially loaded notion + ‘AI’]. A result of this branding, even if implicit, is to encourage the application by laypeople of these agentially loaded notions to the AI technologies themselves. Yet, these notions are appropriate only when applied to agents, which current AI technologies are not; and the concern is that this misapplication creates an incentive to inappropriately attribute trustworthiness or responsibility to AI technologies. We endeavour to show that we have good reason to avoid any general AI policy that uses agentially loaded labelling. We suggest labelling these policies not in terms of some qualification of AI, but rather in terms of our approach to the technology and its wider development and use context – focusing on being trustworthy and responsible about AI, rather than on trustworthy or responsible AI. [ABSTRACT FROM AUTHOR]

Context: It has been reported that photoexcitation of azastilbene compounds like E-1,2-bispyrazinyl-ethylene (bpe) can undergo E → Z photoisomerization of its quaternary salts via the excited triplet state. However, experimentally it is possible to get low fluorescence and photoisomerisation quantum yields in a state with higher internal conversion than intersystem crossing. We modelled bpe and its methylated derivative (bpeMe), as well as its quaternary halogen salts (bpeMeX with X = F−, Cl−, Br− and I−) to study levels of fluorescence, phosphorescence and excited state potential energy surfaces (PES). Results support experimental observations of molecules where the anion of a salt is an efficient electron donor, that molecules with weak electron-donating anions like Cl− to give increased fluorescence and photoisomerization, as compared to molecules with stronger electron-donating anions like I−, which are dominated by competing electron transfer. The fluorescence of bpeMeF and bpeMeCl was found to be stronger than bpeMeBr and bpeMeI. A deep well in the triplet excited state of bpeMeI is considered responsible for the decreased photoisomerization, compared to what was experimentally observed for bpeMeCl. Uniquely, the bpeMeI molecule is characterised by near-zero splitting of the s1 and t1 excited states that can enhance charge transfer. The quaternary salt of bpeMe with stronger electron-donating Br− anion was observed to undergo fluorescence and phosphorescence at much lower energy compared to those with weak electron-donating F− and Cl− anions. This research shows how to control the excited state fluorescence, phosphorescence and isomerization of quaternary halogen salts of methyl derivatives of 1,2-bispyrazinyl-ethylene, which aids experimental design where excited state isomerization is considered. Methods: Geometry optimization, molecular electrostatic potential (MESP), and time dependent density functional theory (TDDFT) calculations were conducted utilizing Gaussian 16 with the B3LYP functional and the 6–31 + G(d,p) basis set. The minimum energy path (MEP) for the E to Z isomerization of the molecules was established employing the Nudged-Elastic-Band (NEB) method, implemented in Orca 4.2. Precise energies of the E → Z isomerization reaction path were determined employing CASSCF and a more accurate multireference method, NEVPT2. [ABSTRACT FROM AUTHOR]

Recent biological surveys of ancient inselbergs in southern Malawi and northern Mozambique have led to the discovery and description of many species new to science, and overlapping centres of endemism across multiple taxa. Combining these endemic taxa with data on geology and climate, we propose the 'South East Africa Montane Archipelago' (SEAMA) as a distinct ecoregion of global biological importance. The ecoregion encompasses 30 granitic inselbergs reaching > 1000 m above sea level, hosting the largest (Mt Mabu) and smallest (Mt Lico) mid-elevation rainforests in southern Africa, as well as biologically unique montane grasslands. Endemic taxa include 127 plants, 45 vertebrates (amphibians, reptiles, birds, mammals) and 45 invertebrate species (butterflies, freshwater crabs), and two endemic genera of plants and reptiles. Existing dated phylogenies of endemic animal lineages suggests this endemism arose from divergence events coinciding with repeated isolation of these mountains from the pan-African forests, together with the mountains' great age and relative climatic stability. Since 2000, the SEAMA has lost 18% of its primary humid forest cover (up to 43% in some sites)—one of the highest deforestation rates in Africa. Urgently rectifying this situation, while addressing the resource needs of local communities, is a global priority for biodiversity conservation. [ABSTRACT FROM AUTHOR]

The need for low-cost and efficient biosorbent materials for the decontamination of heavy metal polluted water is important to abate the toxic effects on humans and the environment. Therefore, the present research reports the adsorption of cadmium ions from an aqueous solution onto alkaline-treated coconut shell (Alk-CCS) powder as a low-cost potential biosorbent. The biosorbent was characterized by SEM, XRD, FTIR, and EDX. Batch biosorption experiments were used to determine the effect of pH, time, temperature, dosage, and concentration on biosorption. The isotherm, kinetic, and thermodynamic modelling of the process was performed. The optimum condition for the adsorption of Cd2+ onto Alk-CCS was a pH of 6.4, adsorbent dosage of 0.2 g, and a contact time of 30 min. Moreover, a maximum monolayer adsorption capacity of 14.22 mg/g was obtained from the Langmuir model for Cd2+ adsorption. From the nonlinear isotherm and kinetics analysis, cadmium ions adsorption on Alk-CCS followed the pseudo-second-order model involving chemical interactions, while the Sips model best fitted the isotherm evaluation. According to the satisfactory fitting to the Sips isotherm model, the adsorption could not be best fitted to the classical adsorption isotherm models such as Langmuir and Freundlich. Thermodynamic parameters indicated that the adsorption of Cd ions on Alk-CCS was feasible, spontaneous (negative value of ∆G°), and exothermic (negative value of ∆H°). Moreover, the nonlinear modelling showed that alkaline modified coconut shell powder is a viable and efficient adsorbent for the removal of cadmium ions from polluted water. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate whether the content of Corporate Social Responsibility (CSR) messages predicts communication outcomes in South African nonprofit organisations (NPOs). The study found a positive association between CSR message content and CSR communication outcomes. Additionally, CSR message content in nonprofit organisations is positively linked to their CSR communication outcomes. Furthermore, support for community-related activities positively impacts CSR communication outcomes, thereby explaining the correlation between CSR message content and communication effectiveness. The study lays the groundwork for non-profit organisations seeking optimisation of their CSR messaging to achieve a wider socio-economic impact on the public at large. These results underscore the importance for nonprofit organisations to strategically develop CSR messages that highlight their support for community-related activities. By emphasising such content in their communication efforts, organisations can enhance their CSR communication outcomes, potentially fostering stronger relationships with stakeholders and garnering increased support for their initiatives. [ABSTRACT FROM AUTHOR]

Context: Micro-hydration of the aminobenzoic acid is essential to understand its interaction with surrounding water molecules. Understanding the micro-hydration of the aminobenzoic acid is also essential to study its remediation from wastewater. Therefore, we explored the potential energy surfaces (PESs) of the para-aminobenzoic acid-water clusters, ABW n , n = 1 - 10 , to study the microsolvation of the aminobenzoic acid in water. In addition, we performed a quantum theory of atoms in molecules (QTAIM) analysis to identify the nature of non-covalent bondings in the aminobenzoic acid-water clusters. Furthermore, temperature effects on the stability of the located isomers have been examined. The located structures have been used to calculate the hydration free energy and the hydration enthalpy of the aminobenzoic acid using the cluster continuum solvation model. The hydration free energy and the hydration enthalpy of the aminobenzoic acid at room temperature are evaluated to be −7.0 kcal/mol and −18.1 kcal/mol, respectively. The hydration enthalpy is in perfect agreement with a previous experimental estimate. Besides, temperature effects on the calculated hydration enthalpy and free energy are reported. Finally, we calculated the gas phase binding energies of the most stable structures of the ABW n clusters using twelve functionals of density functional theory (DFT), including empirical dispersion. The DFT functionals are benchmarked against the DLPNO-CCSD(T)/CBS. We have found that the three most suitable DFT functionals are classified in the following order: PW6B95D3 > MN15 > ω B97XD. Therefore, the PW6B95D3 functional is recommended for further study of the aminobenzoic acid-water clusters and similar systems. Methods: The exploration started with classical molecular dynamics simulations followed by complete optimization at the PW6B95D3/def2-TZVP level of theory. Optimizations are performed using Gaussian 16 suite of codes. QTAIM analysis is performed using the AIMAll program. [ABSTRACT FROM AUTHOR]

Context: Bis(terpyridine)manganese(III) exhibits Jahn–Teller distortion due to the inequivalent occupation of the degenerate eg orbitals of this high-spin d4 pseudo octahedral complex. Due to the spatially constrained nature of the terpyridine ligand, the central Mn-N bonds will always be shorter than the Mn-N terminal bonds, making it more difficult to distinguish between compression and elongation Jahn–Teller structures for bis(terpyridine)manganese(III). Density functional theory (DFT) calculations were utilized as a tool to evaluate the type of Jahn–Teller distortion in the high-spin d4 bis(terpyridine)manganese(III). The nature of the Jahn–Teller distortion calculated does depend upon the choice of density functional approximation (DFA) with the B3LYP, M06, and OLYP-D3 DFAs giving compression and the PW6B95D3, MN15, and MN15-D3 DFAs giving elongation in gas-phase calculations. All solvent-phase calculations yield an elongated structure for the bis(terpyridine)manganese(III) compound, which is yet to be structurally characterized experimentally. However, both gas and solvent OLYP-D3 calculations result in a compressed structure for the only experimentally isolated and characterized bis(terpyridine)manganese(III) complex, specifically the complex with terpyridine = 4′-(4-methylphenyl)-2,2′:6′,2′′-terpyridine. This alignment with the experimentally observed compression Jahn–Teller structure enhances the credibility of OLYP-D3 calculations in reproducing the observed geometries. The compressed Jahn–Teller geometries were near D2d symmetry with the z-axis for compression defined along the Mn-N central bonds. Elongation Jahn–Teller distortion is not possible along the Mn-N central bonds, due to their spatially constrained nature. Thus, elongation occur along one pair of opposite Mn-N terminal bonds that are longer than the other pair of opposite terminal bonds, with shorter central bonds. The highest symmetry of the elongation Jahn–Teller distortion geometry of bis(terpyridine)manganese(III) is C2v. Criteria to distinguish between a compression and elongation Jahn–Teller geometry for bis(terpyridine)manganese(III) are identified. The nature of the singly occupied eg molecular orbital, exhibiting anti-bonding interaction with the nitrogen-p MOs involved, dictates the type of Jahn–Teller distortion that occurs. The low-energy occupied bonding t2g molecular orbitals establish bonds with and undergo mixing with the ligand molecular orbitals. The OLYP-D3 functional is recommended for calculating bis(terpyridine)manganese(III) and related compounds due to its consistent generation of metal–ligand bonds slightly longer than observed in experiments, in line with the required behavior. Additionally, OLYP-D3 offers a realistic electronic structure for Jahn–Teller distorted bis(terpyridine)manganese(III), correctly identifying alpha eg molecular orbitals as the highest occupied molecular orbital and lowest unoccupied molecular orbital in agreement with experimental electrochemical studies. Furthermore, OLYP-D3 accurately reproduces the experimental compression geometry for the only structurally known bis(terpyridine)manganese(III) compound, instilling confidence in its reliability for such calculations. Methods: DFT geometry optimization and frequency calculations were done on the two different modes of Jahn–Teller distortion of bis(terpyridine)manganese(III), using the OLYP, B3LYP, M06, PW6B95D3, and MN15 functionals, with and without the Grimme's D3 dispersion correction, and the 6-311G(d,p) or def2TZVPP basis set, as implemented in Gaussian 16. All optimizations were in the gas phase and also in the solvent phase with CH3CN as implicit solvent using IEFPCM. DFT calculations were utilized to determine the Jahn–Teller effect on the geometry of high-spin d4 bis(terpyridine)manganese(III) complex containing two structurally constrained tridentate ligands. [ABSTRACT FROM AUTHOR]

Biochars are efficient materials for the adsorption of water pollutants. Moreover, the modification of biochars might enhance the adsorption potentials but increase the process cost. Therefore, the search for low-cost unmodified biochars with high adsorption capacity is needed. In this study, we prepared new biochar (PLBC) from low-cost Populus nigra leaves for oil sorption, in an attempt to search for unmodified biochar with high uptake capacity. The biochar was prepared by low-temperature pyrolysis at 350 °C in other to maintain a low process cost. The sorbent characterization revealed the presence of functional groups and surface pores on PLBC desirable for the sorption of oil. A decrease in the surface area of the biochar from 36.82 to 18.55 m2/g, the pore volume from 0.0372 to 0.0152 cm3/g, and the pore diameter from 4.434 to 3.276 nm was obtained after oil sorption. Elemental analysis of PLBC showed carbon content of 55.9% and a biochar yield of 58.6%. PLBC exhibited an oil uptake capacity of 4.634 g/g. The Freundlich and Pseudo-second-order models provided the best fit to the isotherm and kinetic evaluations, respectively, with the involvement of the intraparticle diffusion mechanism. Thermodynamics revealed a physicochemical, endothermic, feasible, and spontaneous oil uptake onto PLBC. High oil desorption (<92.5%) was achieved using petroleum ether as eluent, and PLBC exhibited good potentials for reuse. These investigations revealed the potential of PLBC as a viable low-cost sorbent for the treatment of oil spills. [ABSTRACT FROM AUTHOR]

Context: The search for highly efficient adsorbent materials remains a significant requirement in the field of adsorption for wastewater treatment. Computational study can highly contribute to the identification of efficient material. In this work, we propose a computational approach to study the adsorption of four cationic basic dyes, basic blue 26 (BB26), basic green 1 (BG1), basic yellow 2 (BY2), and basic red 1 (BR1), onto two models of graphene oxide as adsorbents. The main objectives of this study are the assessment of the adsorption capacity of the graphene oxide towards basic dyes and the evaluation of the environmental and temperature effects on the adsorption capacity. Quantum theory of atoms in molecules (QTAIM) analysis has been used to understand the interactions between the dyes and graphene oxides. In addition, adsorption free energies of the dyes onto graphene oxides are calculated in gas and solvent phases for temperatures varying from 200 to 400 K. As a result, the adsorption free energy varies linearly depending on the temperature, highlighting the importance of temperature effects in the adsorption processes. Furthermore, the results indicate that the environment (through the solvation) considerably affects the calculated adsorption free energies. Overall, the results show that the two models of graphene oxide used in this work are efficient for removing dyes from wastewater. Methods: We have optimized the complexes formed by the interaction of dyes with graphene oxides at the PW6B95-D3/def2-SVP level of theory. The SMD solvation model realizes the implicit solvation, and water is used as the solvent. Calculations are performed using the Gaussian 16 suite of program. QTAIM analysis is performed using the AIMAll program. Gibbs free energies as function of temperature are calculated using the TEMPO program. [ABSTRACT FROM AUTHOR]

Interactions between humans and smart products (i.e. digital components integrated in physical Internet of Things devices) are becoming more complex and less visible. Yet designers lack tools to capture these interactions and incorporate them into their design. In this paper we present the Human-Computer-Context Interaction (HCCI) tool that helps the designer to consider the different interactions of the user early in the conceptualisation phase, in order to eventually improve the user experience for smart products. This tool introduces 5 relevant interaction levels to be considered, when defining the context-of-use. In this paper we assess the use of the tool by means of a design challenge with a total of 34 industrial design students, given the task to design a smart kitchen concept. The tool was evaluated by a mixed method approach. Results show that the tool was evaluated as useful and usable during the early concept phase of the design of smart products. Unsupported concepts typically envisioned a single user interacting with one object through explicit interactions. Hence, tool-supported designs were more holistic and better captured interactions with other objects, users, content and services. From this we conclude that the tool can help to detect possible pitfalls of design selections. The tool is aimed to be used in a new product development process by HCI researchers, designers, and developers and is technology independent. Based on observations and participant feedback, we reflect on the strengths and limitations of this tool. [ABSTRACT FROM AUTHOR]

Metal oxide nanoparticles are prospective materials for wastewater treatment because of their natural abundance, low cost, and potent textural characteristics. Among metal oxide nanoparticles, manganese dioxide nanoparticles (MnO2NPs) are promising due to the associated structural flexibility, environmentally friendly nature, good stability, and high activity. However, there is a dearth of research on the use of MnO2NPs as adsorbents for water pollutants. In this work, MnO2NPs were synthesized by a green technique using the aqueous leaf extract of Populus nigra for the adsorption of nortriptyline antidepressant and celestine blue dye. The FTIR, XRD, SEM, EDX, TGA, BET, and pHpzc characterizations revealed the successful synthesis of MnO2NPs, possessing potent surface characteristics. The maximum adsorption capacity of 33.94 mg/g and 60.31 mg/g was obtained for the adsorption of nortriptyline and celestine blue, respectively. Optimum adsorption conditions of pH 7.0, concentration 50 mg/L, and sonication time of 60 min for nortriptyline and 180 min for celestine blue were maintained. The isotherm, kinetic, and thermodynamic evaluation revealed the participation of various processes in the adsorption of the pollutants on MnO2NPs. Moreover, MnO2NPs were successfully regenerated with ethanol and reused for adsorption over five cycles. The findings proved that MnO2NPs are promising materials for the efficient decontamination of nortriptyline and celestine blue from wastewater, especially for the dye pollutant. [ABSTRACT FROM AUTHOR]

In this work, we have investigated the electronic, optoelectronic, optical, and thermodynamic properties of the parent molecules diphenanthro [3,4,5,6-efghi:3′,4′,5′,6′-uvabc]ovalene (C48H18), tribenzo[jk,mn,pq]dibenzo [5,6:7,8] pentapheno [2,1,14,13,12-stuvabcd] ovalene (C60H22), and its derivatives formed by through functionalization with chlorine and potassium atoms. All calculations were performed using Density Functional Theory (DFT) (HSE, ωB97XD, and CAM-B3LYP) and time-dependent density functional theory (TD-DFT), associated with the 6-31G(d) basis set. The results show that the molecules functionalized with potassium atoms have small gap energy values, which gives them good applications in electronics. These same molecules present a non-centrosymmetric architecture with a first hyperpolarizability value higher than that of the reference molecule for nonlinear optics, which is the paranitroaniline molecule. The high values of the average electric field, of the susceptibility, of the refractive index, and the small value of the dielectric constant of the molecules functionalized with potassium allow us to say that these molecules have good optoelectronic and photonic applications. [ABSTRACT FROM AUTHOR]

Ipomoea batatas peel (IBP) is established as a viable lignocellulosic sorbent for wastewater treatment but has not been applied for the decontamination of oil-polluted water. This work reports for the first time the sorption of motor oil from water onto IBP as a natural eco-friendly sorbent. The FTIR spectra of IBP showed several functional groups desirable for efficient uptake of motor oil from water. SEM characterizations revealed an irregular and porous surface morphology, while EDX showed carbon (56.2%) and oxygen (39.0%) as major constituents of IBP sorbent. The BET surface area and pore characterizations of IBP revealed a surface of 5.774 m2/g, a pore volume of 0.00423 cm3/g, and an average pore diameter of 3.062 nm. The Langmuir model presented the best fit to the isotherm oil sorption analysis with a coefficient of determination (R2) of 0.9034 and a sum square error (SSE) of 0.0071. Kinetic modeling revealed that the process conformed to the intraparticle diffusion and pseudo-second-order model, while thermodynamics displayed a physical, endothermic, and feasible uptake of motor oil onto IBP. The oil sorption was found to be dominated by absorption mechanism and hydrophobic interactions. The motor oil-loaded IBP showed 96.2% oil desorption using petroleum ether as eluent. Besides, IBP exhibited efficient recycling and reuse for oil uptake with a decrease from 3.39 (initial uptake) to 2.82 g/g (fourth cycle). These investigations prove that IBP sorbent is a highly efficient biodegradable, eco-friendly, and reusable natural organic material for sequestration of motor oil from water. [ABSTRACT FROM AUTHOR]

Several anthropogenic activities produce radioactive materials into the environment. According to reports, exposure to high concentrations of radioactive elements such as potassium (40K), uranium (238U and 235U), and thorium (232Th) poses serious health concerns. The scarcity of reviews addressing the occurrence/sources, distribution, and remedial solutions of radioactive contamination in the ecosystems has fueled data collection for this bibliometric survey. In rivers and potable water, reports show that several parts of Europe and Asia have recorded radionuclide concentrations much higher than the permissible level of 1 Bq/L. According to various investigations, activity concentrations of gamma-emitting radioactive elements discovered in soils are higher than the global average crustal values, especially around mining activities. Adsorption technique is the most prevalent remedial method for decontaminating radiochemically polluted sites. However, there is a need to investigate integrated approaches/combination techniques. Although complete radionuclide decontamination utilizing the various technologies is feasible, future research should focus on cost-effectiveness, waste minimization, sustainability, and rapid radionuclide decontamination. Radioactive materials can be harnessed as fuel for nuclear power generation to meet worldwide energy demand. However, proper infrastructure must be put in place to prevent catastrophic disasters. [ABSTRACT FROM AUTHOR]

In this research, the mechanism and efficiency of Cr(VI) uptake onto Irvingia gabonensis stem bark extract modified silica gel (IGMS) was reported for the first time. The pristine silica gel (PS) and IGMS adsorbents were characterized by the XRD, FTIR, FESEM, EDX, BET, and TGA techniques. The characterizations proved the successful coating of the plant extract onto silica gel. The FTIR spectra showed the Si–O–Si bands present on the silica gel materials. The FESEM revealed an increase in surface roughness of IGMS after coating with the plant extract, while TGA showed a high thermal stability of both PS and IGMS with over 65% of the initial weight retained at 800 °C. The batch Cr(VI) adsorption revealed optimum uptake at pH 2.0, with a maximum monolayer uptake capacity of 23.26–26.18 mg/g for IGMS at temperatures of 295 to 318 K. The kinetic modeling of Cr(VI) uptake onto PS and IGMS was best fitted by the Elovich model in comparison to the pseudo-second-order, pseudo-first-order, and intraparticle diffusion model. The Langmuir and Freundlich isotherms gave the best fit to the adsorption of Cr(VI) onto IGMS and PS, respectively. Adsorption thermodynamics revealed endothermic, increased randomness and spontaneous removal of Cr(VI) onto IGMS and PS adsorbents. The results revealed that Irvingia gabonensis stem bark extract modified silica gel is a viable and highly efficient adsorbent for the removal of Cr(VI) from Cr(VI)-contaminated effluents. [ABSTRACT FROM AUTHOR]

Despite the potent antimicrobial activity of magnetite nanoparticles (MtNPs), research on the antifungal activity of MtNP against filamentous fungi is rare. In this study, MtNP was synthesized by an inexpensive and easy green approach using the aqueous extract of Ananas comosus (pineapple) peels (AP), and applied as an antifungal agent against the filamentous fungal pathogens Fusarium verticilliodes, Aspergillus flavus, and Alternaria alternata (CGJM3078 and CGJM3006). The AP-mediated MtNP (AP-MtNP) was characterized by the XRD, UV-Visible, FTIR, BET, TGA, SEM, TEM, and EDX techniques. These characterizations revealed the successful synthesis of AP-MtNP by the reducing and stabilizing action of the aqueous extract of AP. The BET analysis showed a high surface area of 233.8 m2/g, while high thermal stability of AP-MtNP was displayed by the TGA. The SEM and TEM images mostly showed spherical AP-MtNPs with an average size of 17.87 nm and a somewhat dispersed and porous surface morphology. The newly synthesized AP-MtNPs exhibited effective antifungal activity against the four fungal strains. [ABSTRACT FROM AUTHOR]

In this research, a novel green tillite-based adsorbent (CMT) was synthesized by modifying the surface of natural/pristine tillite (PT) with Chrysophyllum albidum stem bark extract for the efficient removal of Cr(VI) from water. The physicochemical characteristics of PT and CMT were assessed by the use of the FTIR, XRD, BET, TGA, and SEM techniques. Cardinal adsorptive parameters such as solution pH, contact time, adsorbent dose, and initial concentration were used to optimize the efficiency of PT and CMT for Cr(VI) adsorption. The Elovich kinetic model was noticed to best describe the uptake of Cr(VI) onto PT and CMT. Hence, chemisorption was the rate-controlling step for Cr(VI) uptake onto both PT and CMT. Meanwhile, the Langmuir maximum adsorption capacity of PT and CMT was 51.06 and 291.8 mg g−1 respectively, which was higher than those obtained for most materials used for Cr(VI) uptake. The Langmuir and Freundlich models best describe the equilibrium adsorption data for PT and CMT respectively. The reusability assessment of PT and CMT showed over 90% of the initial Cr(VI) uptake even after the fifth cycle of reuse. Electrostatic interaction and reduction of Cr(VI) were responsible for the removal of Cr(VI) from water onto the green material. The uptake of Cr(VI) was thermodynamically feasible, entropy-driven, and endothermic on both PT and CMT. The outcome of this study revealed that the anchoring of Chrysophyllum albidum stem bark extract on tillite produced a green adsorbent, which was highly efficient for the removal of Cr(VI) from polluted water. [ABSTRACT FROM AUTHOR]

The introduction of Autonomous Military Systems (AMS) onto contemporary battlefields raises concerns that they will bring with them the possibility of a techno-responsibility gap, leaving insecurity about how to attribute responsibility in scenarios involving these systems. In this work I approach this problem in the domain of applied ethics with foundational conceptual work on autonomy and responsibility. I argue that concerns over the use of AMS can be assuaged by recognising the richly interrelated context in which these systems will most likely be deployed. This will allow us to move beyond the solely individualist understandings of responsibility at work in most treatments of these cases, toward one that includes collective responsibility. This allows us to attribute collective responsibility to the collectives of which the AMS form a part, and to account for the distribution of burdens that follows from this attribution. I argue that this expansion of our responsibility practices will close at least some otherwise intractable techno-responsibility gaps. [ABSTRACT FROM AUTHOR]

Copper oxide nanoparticles (CuONPs) have received tremendous attention as efficient adsorbents owing to their low cost, desirable surface area, abundant active sites, potent textural characteristics and high adsorption capacities. However, CuONPs have not been employed to decontaminate water laden with increasing environmental contaminants such as thiazolyl blue and paracetamol. Herein, the adsorption of thiazolyl blue and paracetamol onto green synthesized CuONPs prepared from the aqueous leaf extract of Platanus occidentalis was studied. The BET, SEM, FTIR, XRD, EDX and pH point of zero charge showed the successful synthesis of CuONPs having desirable surface properties with a surface area of 58.76 m2/g and an average size of 82.13 nm. The maximum monolayer adsorption capacities of 72.46 mg/g and 64.52 mg/g were obtained for thiazolyl blue and paracetamol, respectively. The Freundlich, pseudo-second-order and intraparticle diffusion models were well fitted to the adsorption of both pollutants. The pH studies suggested the predominance of electrostatic and weaker intermolecular interactions in the adsorption of the thiazolyl blue and paracetamol, respectively. Spontaneous, physical, endothermic and random adsorption of the pollutants on CuONPs was obtained from the thermodynamic consideration. The biosynthesized CuONPs were found to be highly reusable and efficient for the adsorption of thiazolyl blue and paracetamol from water. [ABSTRACT FROM AUTHOR]

The contamination of environmental waters with heavy metals and radionuclides is increasing because of rapid industrial and population growth. The removal of these contaminants from water via adsorption onto metal nanoparticles is an efficient and promising technique to abate the toxic effects associated with these pollutants. Among metal nanoparticle adsorbents, zinc oxide nanoparticles (ZnONPs) have received tremendous attention owing to their biocompatibility, affordability, long-term stability, surface characteristics, nontoxicity, and powerful antibacterial activity against microbes found in water. In this review, we considered the adsorption of heavy metals and radionuclides onto ZnONPs. We examined the isotherm, kinetic, and thermodynamic modeling of the process as well as the adsorption mechanism to provide significant insights into the interactions between the pollutants and the nanoparticles. The ZnONPs with surface areas (3.93 to 58.0 m2/g) synthesized by different methods exhibited different adsorption capacities (0.30 to 1500 mg/g) for the pollutants. The Langmuir and Freundlich isotherms were most suitable for the adsorption process. The Langmuir separation factor indicated favorable adsorption of all the pollutants on ZnONPs. The pseudo-second-order kinetics presented the best for the adsorption of the adsorbates with regression values in the range of 0.986–1.000. Spontaneous adsorption was obtained in most of the studies involving endothermic and exothermic processes. The complexation, precipitation, ion exchange, and electrostatic interactions are the probable mechanisms in the adsorption onto ZnONPs with a predominance of complexation. The desorption process, reusability of ZnONPs as well as direction for future investigations were also presented. [ABSTRACT FROM AUTHOR]

Global carbon reduction targets can be facilitated via energy storage enhancements. Energy derived from solar and wind sources requires effective storage to guarantee supply consistency due to the characteristic changeability of its sources. Supercapacitors (SCs), also known as electrochemical capacitors, have been identified as a key part of solving the problem. In addition, SCs can provide solutions to charging electric vehicles much faster than is possible using lithium-ion batteries. Nevertheless, further research into high-performance supercapacitor development is urgently needed to enable their use for effective large electricity storage. In general, energy utilization will subsequently depend on consumers/industries that are generating, storing and utilizing energy more effectively, with SCs being identified as one of the emerging technologies for intermittent energy storage, harvesting and high-power delivery. In this review, we have highlighted the historical information concerning the evolution of supercapacitor technology and its application as an energy storage device. A detailed account of the device's electrode materials/electrolytes, processes, designs, and various applications is discussed. The primary characteristics of the energy storage system, such as capacitance/capacity, operating temperature, energy/power density, operating potential, kinetic storage mechanism, cycling lifetime, self-discharge, voltage holding/floating test, and the makeup of the electrode materials, are also briefly discussed. In addition, based on the current research scenario, the potential, challenges, and development patterns for SCs are summarized. [ABSTRACT FROM AUTHOR]

Optoelectrical, electronic, and thermodynamic properties of {6}cycloparaphenylene ({6}CPP) and its derivative, N,N-dimethyl-diaza{6}cycloparaphenylene (DMDA{6}CPP), are theoretically investigated in this work. Using the density functional theory (DFT) and time-dependent DFT (TD-DFT) supported by the APFD and B3LYP-D3 functionals and the 6-311++G (d,p) basis set, the new compound, DMDA{6}CPP, revealed an optical band gap E opt = 1.20 eV. With the lowest energy transition excited state recorded at λ = 1029 nm and associated light-harvesting efficiency (LHE) = 25 % , this derivative demonstrates good characteristics as absorber material in organic solar cell (OSC) devices. The analysis of its charge transport abilities exhibits a ratio of hole/electron reorganization energies λ h / λ e = 0.68 , providing very consistent information on good hole transport abilities. Moreover, this derivative of {6}CPP registered amazing linear and NLO properties with polarizability and first-order hyperpolarizability α = 626.7 a.u and β = 10195.8 a.u, respectively. These values are far higher than those of both para-nitro aniline (p-NA) and urea commonly used as reference molecules in linear and nonlinear optics, positioning this molecule as a perfect candidate for NLO applications and optoelectronics. Molecular atomization energy calculation, spectra analysis, and thermodynamic descriptor calculations have also revealed a very stable structure. [ABSTRACT FROM AUTHOR]

We have investigated the structures, electronic properties, hole and electron mobilities of perfluorinated, perchlorinated and percyanated coronene molecules, using the density functional theory (DFT) and Time Dependent DFT (TDDFT) at the B3LYP-D3/6-311++G(d,p) and ω B97XD/6-311++G(d,p) levels and Markus-Hush charge transfer theory. The calculated geometric parameters for coronene and perchlorocoronene are in good agreement with the experimental data. Our theoretical investigations have shown that B3LYP-D3 functional is suitable to well define vibrational assignments for studied molecules. The quantified effect of the complete substitution of peripheral hydrogen atoms with cyanide groups for the key properties relevant for optoelectronic and photonics such as electron affinities, ionization energies, HOMO-LUMO energies, reorganisation energies, optical absorption spectra, and electron mobilities were discussed. Compared to perfluorination and perchlorination, the percyanation of coronene considerably increases the adiabatic/vertical electron affinities (AEAs/VEAs), the electron mobilities, the HOMO-LUMO gap and reduces the LUMO energy level thus indicating an ambipolar behavior and air-stable material. We have discussed the possible implications of cyanide groups as important substitutes for the design of the new organic compounds useful in electronics. [ABSTRACT FROM AUTHOR]

Summary: Rationale: Early surgery is recommended for hip fractures. Main result: In this study only one-third of subjects with hip fractures were admitted within 24 h of the fracture, and surgery was delayed beyond 48 h in the majority. Significance: These findings highlight the need to improve access to care for hip fracture subjects. Purpose: There is limited data on the timing of admission and surgery following a low trauma hip fracture (HF) in South Africa (SA). Methods: A prospective, observational study was conducted at public and private hospitals in three provinces, Gauteng (GP), KwaZulu-Natal (KZN) and the Western Cape (WC), in SA to determine time from fracture to admission and from admission to surgery in patients presenting with low trauma HF. Associations with delayed admission and surgery were explored using logistic regression. Results: The median age of the 1996 subjects was 73 years (IQR 63–81 years), the majority were women (1346, 67%) and 1347 (67%) were admitted to the public hospitals. In one-third of subjects (661, 33%), admission was delayed to beyond 24 h after the fracture. There was a significantly longer time to admission in public compared to private hospitals (21 h [IQR 10.0–48.5] versus 6 h [IQR 3.3–14.1], p < 0.001), in subjects < 65 years, the WC and when admission occurred on a weekday. Surgery was delayed beyond 48 h in the majority (1272, 69%) of subjects and was significantly longer in public compared to private hospitals (130 h [IQR 62.6–212.4] versus 45.4 h [IQR 24.0–75.5], p < 0.001), in KZN, and when admission occurred after hours. Conclusion: The burden of HFs is higher at public hospitals in SA, where there is a significant delay in admission after a fracture and surgery after admission. This highlights the need for a review of HF care pathways, resources and policies. [ABSTRACT FROM AUTHOR]

TTP is a life-threatening disorder with limited pharmaceutical treatment options. Recently, the potential of streptokinase in the treatment of acquired TTP was demonstrated in humans in vitro, and in vivo in a mouse model. We aimed to determine the in vitro and in vivo effects of streptokinase in an established Papio ursinus model of acquired TTP. In vitro: VWF activities & multimer patterns and thromboelastograms were assessed with increasing concentrations of streptokinase. In vivo: After induction of TTP, escalating streptokinase doses (ranging from 50,000 to 900,000 IU) were administered, and the effects of streptokinase assessed on peripheral blood counts, fibrinolysis, VWF activities & multimer patterns and thromboelastograms. In an extension of the study, high-dose streptokinase (1,500,000–3,000,000 IU) was administered to another baboon. After spiking, fibrinolysis with loss of large VWF multimers was observed at [2200 IU/mL]—roughly equivalent to 1,500,000 IU. However, administration of escalating intravenous streptokinase doses had no in vivo effect on the TTP phenotype, and in vivo increases in plasmin activity were mild when compared with baseline, even at high doses. Minimal effect on VWF multimer patterns was observed but only at doses ≥ 1500,000 IU. Streptokinase is not effective in resolving TTP in a Papio ursinus model of TTP, possibly due to limited activation of the baboon fibrinolytic system. Modifications to this model, the use of alternative higher animal models, or alternative thrombolytics, should be considered to establish proof-of-concept. [ABSTRACT FROM AUTHOR]

Aluminium oxide (ALU) and carbon-coated aluminium oxide modified with Kigelia africana leaf extract (KECA) were employed for the removal of toxic hexavalent chromium (Cr(VI)) from the aqueous phase. The adsorbents (ALU and KECA) were characterized by TGA, BET, FESEM, FTIR, Raman and XRD spectroscopic techniques. The potential of KECA and ALU to remove Cr(VI) from simulated wastewater was optimum at pH 2, sorbent dose of 0.025 g and a contact time of 200 min. Meanwhile, the uptake capacity of KECA and ALU was enhanced with an increase in sorbent dose, contact time and initial Cr(VI) concentration. The uptake of Cr(VI) onto the adsorbents ALU and KECA was kinetically best described by the pseudo-second-order and Elovich models, respectively. Besides, the equilibrium data acquired for ALU and KECA obeyed Freundlich and Langmuir isotherm models, respectively. ALU and KECA were observed to have optimum adsorption capacity of 56.45 mg g−1 and 258.2 mg g−1, respectively. The adsorption of Cr(VI) onto the adsorbents was thermodynamically feasible, endothermic in nature and entropy-driven. A decrease in efficiency was observed on regeneration of the absorbents, thus limiting their reusability. However, the presence of functional groups with reducing property in the extract of Kigelia africana leaves was noticed to enhance the capacity of the adsorbent to abstract Cr(VI) from the solution. Hence, this study demonstrates the potential of KECA to sequestrate Cr(VI) from an aqueous solution and provides a reference for its application to the treatment of Cr(VI)-laden industrial wastewater. [ABSTRACT FROM AUTHOR]

In the present study, we theoretically determine the optoelectronic, electronic, nonlinear optical (NLO) and thermodynamic properties of new materials from the conjugated organic polymer poly (3,4-ethylenedioxythiophene) (PEDOT) doped with halogens (fluorine and chlorine), combined with the organic semiconductor 4-[2-(2-N, N-dihydroxy amino thiophene) vinyl] benzenamine (DATVB). The molecular geometry of the ground state, the optoelectronics and electronic parameters have been calculated by combining the 6-311++G (d, p) basis set with various functionals of the density functional theory (DFT). The functionals B3LYP and CAM-B3LYP have been used for NLO parameters. The energy gaps obtained for all the compounds are less than 3.0 eV. These results clearly show that PEDOT and its derivatives can be considered as good semiconductors. They can be tested for use in the manufacture of organic solar cells (OSC) and organic light-emitting diodes (OLED). The first order hyperpolarizabilities of these PEDOT hybrid compounds are much higher than those of the reference compound for NLO applications, namely para-nitroaniline (p-NA), which opens up a new field of application for PEDOT in NLO devices. The thermodynamic parameters such as the zero-point vibrational energy (ZPVE), the enthalpy (H), the heat capacity at constant volume (cv), the entropy (S) and the free energy (G) have been calculated and are reported herein. [ABSTRACT FROM AUTHOR]

Development of wearable mental workload (MWL) measures thrives, especially as leveraged by Industry 4.0. When employees object to wearing such gauges; however, research efforts might end up redundant. Based on self-determination and communication theories, this study assumed that employees' acceptability of wearable MWL-monitoring is shaped by framing characteristics in corporate communication. Specifically, we hypothesized that acceptability depends on how (1) the technology's goals and (2) context of implementation is framed. A pilot study (N = 150) revealed that framing wearable MWL-monitoring in terms of serving intrinsic goals (e.g., improving health) in an autonomy-supportive context (e.g., allowing discussion) induced a higher employee acceptability, compared to framing the technology in terms of serving extrinsic goals (e.g., increasing productivity) in a controlling context (e.g., mandating use). A subsequent pre-registered study (N = 350) could, however, not replicate this result. Instead, higher acceptability was associated with higher technology readiness, lower education levels, and being a woman (for the trust component of acceptability). Independent of conditions, mean acceptability, interestingly, panned out neutral. The current work is thereby the first exploring the complexities of employee acceptability of wearable MWL-monitoring and, based on open-ended questions, finally suggests that privacy management might be the most pivotal explanatory variable. [ABSTRACT FROM AUTHOR]

Multiwalled carbon nanotubes/quartzite nanocomposite modified with the extract of Dacryodes edulis leaves was synthesized and designated as Q, which was applied for the removal of Cr(VI) from water. The adsorbents (PQ and Q) were characterized using the SEM, EDX, FTIR, TGA, XRD, and BET analyses. The XRD revealed the crystalline composition of the nanocomposite while the TGA indicated the incorporated extract as the primary component that degraded with an increase in temperature. The implication of the modifier was noticed to enhance the adsorption capacity of Q for Cr(VI) by the introduction of chemical functional groups. Optimum Cr(VI) removal was noticed at a pH of 2.0, adsorbent dose (50 mg), initial concentration (100 mg dm−3), and contact time (180 min). The kinetic adsorption data for both adsorbents was noticed to fit well to the pseudo-second-order model. The adsorption equilibrium data were best described by the Langmuir model. The uptake of Cr(VI) onto PQ and Q was feasible, endothermic (ΔH: PQ = 1.194 kJ mol−1 and Q = 34.64 kJ mol−1) and entropy-driven (ΔS : PQ = 64.89 J K−1 mol−1 and q = 189.7 J K−1 mol−1). Hence, the nanocomposite demonstrated potential for robust capacity to trap Cr(VI) from aqueous solution. [ABSTRACT FROM AUTHOR]

Hydroxybenzophenone (HBP) molecules have their applications in commercial sunscreens as an UV chromophore because of their photostability and lack of reactivity after several hours of irradiation. They are usually photoexcited from the ground state chelated enol form to excited state where it undergoes proton transfer to chelated keto form and undergoes dihedral twisting to the ground state twisted keto form before going back to enol form. In this research, the three proposed isomers of five substituted 2-hydroxybenzophenones were modelled with additional three conformational changes in the ground state chelated enol and the results are related to the available experimental observations in solvents acetonitrile, n-dimethylformamide and dimethylsulfoxide. A significant difference in reduction potential, electron affinity and molecular properties was observed within the four ground state conformations and also the two excited-state proton transfer geometries for each of the five derivatives. The nature of the solvents also had significant effects on the electron affinity, HOMO, LUMO and energy bandgap of the molecules. The best possible conformation from the theoretical models that better described the experimental observations is the ground state trans chelated enol (named M1d) because of the close range of its reduction potential values and their strong level of correlation to that of the experiment and also a close range of its λmax values to that of the experiment. [ABSTRACT FROM AUTHOR]

Metallic nanoparticles (NPs) have gained significant attention in recent years due to their efficiency in the adsorption of water pollutants. Except for magnetic NPs, metallic NPs are rarely used in oil sorption studies, due to the difficulty in recovering the NPs from the treated water. This study reports for the first time the application of ZnONPs for oil spill treatment. The ZnONPs were impregnated onto Musa acuminata peel (MP) support to form a novel material (ZnOMP), which was utilized for the sorption of oil from synthetic oil spills. The as-prepared sorbents were characterized by the SEM, EDS, BET, FTIR, FE-SEM, TGA, and XRD techniques. The presence of 31.32-nm average-sized ZnONPs enhanced the oil uptake characteristics, with clear affinity for the oil phase in comparison to the pristine MP. A maximum sorption capacity of 4.146 g/g and 5.236 g/g was obtained for biosorbents MP and ZnOMP, respectively, which was higher than most reported sorbents. The Freundlich model presented the best fit for the isotherm data, while the pseudo-second-order model was most suited for the kinetics. The presence of competing heavy metal ions in solution did not have any significant effect on the oil sorption capacity onto ZnOMP. The sorption mechanism was attributed to absorption and hydrophobic interactions. ZnONPs impregnated onto the biomass enhanced the spontaneity of oil uptake at higher temperatures. Over 82% desorption of the oil contaminant from the biosorbents was achieved during recovery, using petroleum ether and n-pentane as eluents. Concisely, ZnONPs enhanced the uptake and hydrophobic characteristic of MP biomass and showed good recovery and reusability. Thus, the application of ZnONPs impregnated onto biosorbents in oil spill treatment is highly recommended. [ABSTRACT FROM AUTHOR]

In this research, zinc oxide nanoparticles (ZnONPs) were prepared via a facile one-pot chemical precipitation approach and applied in the adsorption of bromophenol blue (BRB) and as antifungal agents against the filamentous fungi and plant pathogens; Alternaria alternata CGJM3078, Alternaria alternata CGJM3006 and Fusarium verticilliodes CGJM3823. The ZnONPs were characterized by the UV–Vis, FTIR, XRD, TGA, BET, SEM, TEM, and EDX techniques, which showed efficient synthesis. The characteristics ZnO UV–Vis absorption band was observed at 375 nm, while the XRD showed an average ZnONPs crystalline size of 47.2 nm. The SEM and TEM images showed an irregular shaped and aggregated porous structure of 65.3 nm average-sized ZnONPs. The TGA showed 22.9% weight loss at 800 °C indicating the high thermal stability of ZnONPs, while BET analysis revealed a surface area, pore volume and pore diameter of 9.259 m2/g, 0.03745 cm3/g and 9.87 nm respectively. The Freundlich, pseudo-second-order, and intra-particle diffusion models showed R2 > 0.9494 and SSE < 0.7412, thus, exhibited the best fit to the isotherm and kinetics models. Thermodynamics revealed feasible, endothermic, random, and spontaneous adsorption of BRB onto the synthesized ZnONPs. The antifungal assay conducted depicts strong antifungal activities against all three tested fungi. Noticeably, ZnONPs (0.002–5 mg/mL) showed maximum activities with the largest zone of inhibition against A. alternata CGJM 3006 from 25.09 to 36.28 mm. This was followed by the strain F. verticilliodes CGJM 3823 (range from 23.77 to 34.77 mm) > A. alternata CGJM3078 (range from 22.73 to 30.63 mm) in comparison to Bleach 5% (positive control). Additionally a model was proposed based on the possible underlying mechanisms for the antifungal effect. This research demonstrated the potent use of ZnONPs for the adsorption of BRB and as effective antifungal agents. [ABSTRACT FROM AUTHOR]

In this work, we study the influence of different metals on the electronic, linear, and nonlinear optical properties of phenalenyl based complexes by using the density functional theory (DFT) method through the functional B3LYP and the basis set 6-31++G(d,p). The experimentally known zinc-ethyl-dimethyl-phenalenyl (ZEP) has a DFT calculated gap energy Egap of 3.12 eV and a second-order static hyperpolarizability γ0 of 106711.86 au. By doping zinc with copper, we have obtained copper-ethyl-dimethyl-phenalenyl (CEP) with a DFT calculated gap energy Egap of 2.43 eV and a second-order static hyperpolarizability γ0 of 142177.38 au. The calculated average polarizabilities, first- and second-order static hyperpolarizabilities show that the molecular structures are promising materials for application in the nonlinear optical (NLO) devices. Hole and electron mobilities are respectively 2 × 10−3 cm2 V−1 s−1 and 51 × 10−3 cm2 V−1 s−1 for the ZEP dimer. Similarly, the CEP holes and electrons mobilities are respectively 14,336 × 10−3 cm2 V−1 s−1 and 2039 × 10−3 cm2 V−1 s−1. These values show that the proposed CEP molecule as well as ZEP have good charge transfer properties that can be used in data storage and electronic devices, thin films, and field effect transistors. [ABSTRACT FROM AUTHOR]

Summary: The hip fracture rates in South Africa were used to create ethnic-specific FRAX® models to facilitate fracture risk assessment. Introduction: The aim of this study was to develop FRAX models to compute the 10-year probability of hip fracture and major osteoporotic fracture and assess their potential clinical application. Methods: Age- and sex-specific incidence of hip fracture and national mortality rates were incorporated into a FRAX model for the White, Black African, Coloured and Indian population of South Africa. Age-specific 10-year probabilities of a major osteoporotic fracture were calculated in women to determine fracture probabilities at a femoral neck T score of -2.5 SD, or those equivalent to a woman with a prior fragility fracture. Fracture probabilities were compared with those from selected countries. Results: Probabilities were consistently higher in Indian than in Coloured men and women, in turn, higher than in Black South Africans. For White South Africans, probabilities were lower than in Indians at young ages up to the age of about 80 years. When a BMD T score of −2.5 SD was used as an intervention threshold, FRAX probabilities in women age 50 years were approximately 2-fold higher than in women of the same age but with an average BMD and no risk factors. The increment in risk associated with the BMD threshold decreased progressively with age such that, at the age of 80 years or more, a T score of −2.5 SD was no longer a risk factor. Probabilities equivalent to women with a previous fracture rose with age and identified women at increased risk at all ages. Conclusions: These FRAX models should enhance accuracy of determining fracture probability amongst the South African population and help guide decisions about treatment. [ABSTRACT FROM AUTHOR]

Background: Data on the factors that influence mortality after surgery in South Africa are scarce, and neither these data nor data on risk-adjusted in-hospital mortality after surgery are routinely collected. Predictors related to the context or setting of surgical care delivery may also provide insight into variation in practice. Variation must be addressed when planning for improvement of risk-adjusted outcomes. Our objective was to identify the factors predicting in-hospital mortality after surgery in South Africa from available data. Methods: A multivariable logistic regression model was developed to identify predictors of 30-day in-hospital mortality in surgical patients in South Africa. Data from the South African contribution to the African Surgical Outcomes Study were used and included 3800 cases from 51 hospitals. A forward stepwise regression technique was then employed to select for possible predictors prior to model specification. Model performance was evaluated by assessing calibration and discrimination. The South African Surgical Outcomes Study cohort was used to validate the model. Results: Variables found to predict 30-day in-hospital mortality were age, American Society of Anesthesiologists Physical Status category, urgent or emergent surgery, major surgery, and gastrointestinal-, head and neck-, thoracic- and neurosurgery. The area under the receiver operating curve or c-statistic was 0.859 (95% confidence interval: 0.827–0.892) for the full model. Calibration, as assessed using a calibration plot, was acceptable. Performance was similar in the validation cohort as compared to the derivation cohort. Conclusion: The prediction model did not include factors that can explain how the context of care influences post-operative mortality in South Africa. It does, however, provide a basis for reporting risk-adjusted perioperative mortality rate in the future, and identifies the types of surgery to be prioritised in quality improvement projects at a local or national level. [ABSTRACT FROM AUTHOR]

Involvement of users in the design process is generally viewed favourably, both within academia and industry. Their involvement can be seen as a strategy for designers to clarify their design task and reduce uncertainties in the design process. Simultaneously, there is a lack of understanding about the impact that user involvement has on students and how they experience doing so. This paper reports on a study where students were asked to self-report their motivation and self-confidence throughout a design exercise, stretching 11 days, with surveys repeating daily. Additionally, students were asked to indicate which—if any—strategies of user involvement they used every day. We find that students self-reported motivation did not change statistically significantly, while self-confidence did change. However, in neither case did student's involvement of end-users impact how motivated or self-confident they were. We discuss our results in relation to existing research on method use in general and user involvement in particular and conclude with some suggestions for future work. [ABSTRACT FROM AUTHOR]

Robotic and artificially intelligent (AI) systems are becoming prevalent in our day-to-day lives. As human interaction is increasingly replaced by human–computer and human–robot interaction (HCI and HRI), we occasionally speak and act as though we are blaming or praising various technological devices. While such responses may arise naturally, they are still unusual. Indeed, for some authors, it is the programmers or users—and not the system itself—that we properly hold responsible in these cases. Furthermore, some argue that since directing blame or praise at technology itself is unfitting, designing systems in ways that encourage such practices can only exacerbate the problem. On the other hand, there may be good moral reasons to continue engaging in our natural practices, even in cases involving AI systems or robots. In particular, daily interactions with technology may stand to impact the development of our moral practices in human-to-human interactions. In this paper, we put forward an empirically grounded argument in favor of some technologies being designed for social responsiveness. Although our usual practices will likely undergo adjustments in response to innovative technologies, some systems which we encounter can be designed to accommodate our natural moral responses. In short, fostering HCI and HRI that sustains and promotes our natural moral practices calls for a co-developmental process with some AI and robotic technologies. [ABSTRACT FROM AUTHOR]

In this work, we propose a modified model of graphene oxide nanosheet (GON), based on the Lerf-Klinowski model, through which we attach a carboxyl group (GON-COOH) to the non-equivalent C atom of coronene-based graphene oxide with formation of sp3-like orbital bond. Beryllium, boron, nitrogen, oxygen, and fluorine atoms are integrated into the GON at identical sites in order to study their impact on the physical and chemical properties of GON. Our aim is to propose new efficient materials for applications in optoelectronics and nonlinear optics (NLO). Chemical reactivity and structural, optical, and nonlinear optical properties of GON and its derivatives GON-X (X: Be, B, N, O, and F atoms) were investigated by using the density functional theory (DFT) at the B3LYP-D3/6-31+G(d,p) level of theory. According to the results obtained, the binding energy per atom of GON compound decreases slightly with addition of atoms of the second period elements of the periodic table. The GON-F compound exhibits the smallest value of gap energy compared to other studied compounds and can then be considered a proficient candidate for photovoltaic applications. In regard to NLO properties, we found that the studied models of GON compound theoretically exhibit a larger value of the first static hyperpolarizability than urea, the reference compound for NLO properties. [ABSTRACT FROM AUTHOR]

The synthesis of derivatives of bio-based lubricants from vegetable oil as an alternative to petroleum oil is significant due to the oil crisis, global warming, higher demand and serious environmental threat. In this study, the molecular properties of three derivatives of oil derived from Plukenetia conophora seeds, namely Plukenetia conophora oil (PK), rpoxidised Plukenetia conophora oil (EP) and poly(hydroxybutanethiol-ether) derivative of Plukenetia conophora oil (BP), were examined in acidic media and crystal form. The derivative BP has the highest resistance to acidic attack as evident from their poor interaction with acidic H3O+ from both HCl and HNO3. BP also has the best tendency of forming a crystal as evident from the lowest atomic diffusion in crystal model (L12). However, the result of the molecular electrostatic potential (MESP) analysis shows that BP has more electron-deficient surface compare to EP derivatives. The derivative BP is also found to have the lowest potential energy and higher root means square deviation (RMSD) of its atoms. Density clustering analysis further confirms that BP did not retain its most stable conformation for a longer period of simulation compared to PK and EP. The most visited conformation from the hierarchical and density clustering also corresponds to the minimum potential energy on the potential energy surface. Graphical abstract [ABSTRACT FROM AUTHOR]

We show that positive surjective isometries between symmetric spaces associated with semi-finite von Neumann algebras are projection disjointness preserving if they are finiteness preserving. This is subsequently used to obtain a structural description of such isometries. Furthermore, it is shown that if the initial symmetric space is a strongly symmetric space with absolutely continuous norm, then a similar structural description can be obtained without requiring positivity of the isometry. [ABSTRACT FROM AUTHOR]

Pollution of environmental waters and ecosystems is increasing. Adsorption is an effective technique for water decontamination, but is limited by the cost of commercial adsorbents such as activated carbon. Research has thus focused on the recycling and transformation of biowaste as low-cost, biodegradable adsorbents. In particular, banana peel is promising for commercial use due to its wide availability and efficiency. Here, we review the use of natural banana peel for the biosorption of pollutants from water. We discuss the factors controlling pollutants removal, and the regeneration and reuse of the biosorbent. pH of 5.0 to 7.0 is favorable for the removal of cationic pollutants, while pH of 2.0 to 4.0 is suitable for anionic pollutants. Generally, higher pollutant concentration induces lower removal, whereas higher banana peel dosage induces higher removal. Banana peel exhibits efficient removal of pollutants at various temperatures, with adsorption capacities mostly within 1–100 mg/g. Nitric acid is the most efficient eluent for heavy metal desorption from banana peel. Most studies showed efficient biosorbent reuse up to five cycles and above. We also discuss the thermodynamics, kinetics and isotherms of the adsorption process. [ABSTRACT FROM AUTHOR]

Populations of adaptable mesopredators are expanding globally where passive rewilding and natural recolonization are taking place, increasing the risk of conflict with remaining livestock farmers. We analysed data from two social surveys of farmers in the Karoo, South Africa, where black-backed jackals (Canis mesomelas) and caracals (Caracal caracal) have re-emerged as a threat to sheep farms in the context of falling agricultural employment and the expansion of natural areas. We show that irrespective of measurement approach, lethal control of mesopredators in this fragmented socio-economic landscape was associated with increased livestock losses the following year. Terrain ruggedness was positively, and number of farmworkers negatively, associated with livestock losses. Our study provides further evidence that lethal control of mesopredators in this context is probably counter-productive and supports calls to develop, share and financially support a range of non-lethal methods to protect livestock, especially where natural recolonization of mesopredators is occurring. A graphical abstract can be found in Electronic supplementary material. [ABSTRACT FROM AUTHOR]

Natural-based polyols are seen by polyurethane industries as an alternative to the petroleum-based polyols because of increasing challenges due to the oil crisis and global warming. In this research, four different derivatives of bio-polyols are examined, which include the precursor Jatropha curcas oil (JC) that was extracted from Jatropha curcas seeds, as well as the derivatives epoxidated-polyol (EJ), hydroxylated epoxy-polyol (JP) and epoxy-polyurethane (JU). The computational studies provide more insight into their experimentally observed properties and can be useful in further customized design of this type of bio-polyols for industrial application. Results show that the JU monomer is more stable in terms of potential energy, level of atomic fluctuation, diffusion, radial distribution function, and with properties indicating the possibility of forming the best crystal solid. Monomer JU is also found to have the best resistance to acidic attack, using the results from the interaction energy, radial distribution function (RDF) and level of diffusion. [ABSTRACT FROM AUTHOR]

This study presents the effects of substituent groups R1 and R2 of β-diketonato ligands (R1COCHCOR2)− in [Fe(β-diketonato)3] complexes, on the interaction energy between the ligand fragments and the central iron(III) atom, coupled with the nonlinear optical properties and electronic properties of the [Fe(β-diketonato)3] molecules. The results show that a CF3 group on the ligand reduces the nucleophilicity of the Fe atom and favours stability of the mer isomer above the fac isomer, contrary to what is observed in other unsymmetrically substituted molecules without a CF3 substituent group. The reduction of the molecules results in the weakening of the Fe–O coordination bonds, but increasing strength of the C–O covalent bonds of the ligands. The molecules that have favourable experimental reduction potentials (more positive values) are characterised by lower ionisation potential of the reduced iron(II), lower inductive effect and a lower energy of the lowest occupied molecular orbital (LUMO) before reduction (iron(III)), but by higher chemical potential and higher LUMO energy level after reduction (iron(II)). The experimental reduction potentials are found to correlate significantly with the inter-fragment total energy of interaction (ΔEtot) between the β-diketonato ligands and the iron(III) atom (R2 = 0.948), with a mean absolute deviation (MAD) of the predicted reduction potential of 0.073. Also, the contribution of electrical energy (EL) to the interaction energy (ΔEtot) correlates significantly with the experimental reduction potential (R2 = 0.951), resulting in an even better prediction of reduction potential (MAD = 0.067). It is observed that ring substituents (Ph, C4H3O, C4H3S), dipole moment and polarisability have a greater effect on the hyperpolarisability of the molecules, than merely the presence of a more withdrawing substituent, like CF3. Therefore, molecule [Fe(PhCOCHCOH)3] with a phenyl ring substituent is found to be the compound best suited for nonlinear optical (NLO) applications, extraordinarily higher than the other molecules of this study. [ABSTRACT FROM AUTHOR]

Purpose of Review: We review the international evolution of HIV and solid organ transplantation over 30 years. We emphasise recent developments in solid organ transplantation from HIV-infected to HIV-uninfected individuals, and their implications. Recent Findings: In 2017, Johannesburg, South Africa, a life-saving partial liver transplant from an HIV-infected mother to her HIV-uninfected child was performed. This procedure laid the foundation not only for consideration of HIV-infected individuals as living donors, but also for the possibility that HIV-uninfected individuals could receive organs from HIV-infected donors. Summary: Recent advances in this field are inclusion of HIV-infected individuals as living organ donors and the possibility of offering HIV-uninfected individuals organs from HIV-infected donors who are well-controlled on combination antiretroviral therapy (cART). The large number of HIV-infected individuals on cART is an unutilised source of otherwise eligible living organ donors. HIV-positive-to-HIV-negative organ transplantation has become a reality, providing possible new therapeutic options to address extreme organ shortages. [ABSTRACT FROM AUTHOR]