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The combined effects of substrate temperature, substrate orientation, and energetic particle impingement on the structure of GaN films grown by reactive radio-frequency magnetron sputtering are investigated. Monte-Carlo based simulations are employed to analyze the energies of the species generated in the plasma and colliding with the growing surface. Polycrystalline films grown at temperatures ranging from 500 to 1000 °C clearly showed a dependence of orientation texture and surface morphology on substrate orientation (c- and a-plane sapphire) in which the (0001) GaN planes were parallel to the substrate surface. A large increase in interplanar spacing associated with the increase in both a- and c-parameters of the hexagonal lattice and a redshift of the optical bandgap were observed at substrate temperatures higher than 600 °C. The results showed that the tensile stresses produced during the film's growth in high-temperature deposition ranges were much larger than the expected compressive stresses caused by the difference in the thermal expansion coefficients of the film and substrate in the cool-down process after the film growth. The best films were deposited at 500 °C, 30 W and 600 °C, 45 W, which corresponds to conditions where the out diffusion from the film is low. Under these conditions the benefits of the temperature increase because of the decrease in defect density are greater than the problems caused by the strongly strained lattice that occurr at higher temperatures. The results are useful to the analysis of the growth conditions of GaN films by reactive sputtering. [ABSTRACT FROM AUTHOR]

In this study, an innovative sorbent that is obtained by shoe soles waste was proposed. This low‐cost sorbent was tested for the removal of yellow Bezacryl (YB) from aqueous solutions in batch reactor. The central composite design (CCD) technique and the response surface methodology (RSM) were both applied to study the effect of operating parameters, namely initial YB concentration (Z1), shoe soles waste sorbent dosage (Z2), and pH of the medium (Z3); and determine their optimum giving the highest YB sorption yield. The experimental factors levels studied were respectively 10 ≤ [YB]0 ≤ 50 (mg/L), 0.1 ≤ [sorbent] ≤ 1 (g/250 mL), and 2 ≤ pH ≤ 10. The model equation for YB sorption yield was developed using Microsoft EXCEL Software and the predicted values were found to be in good agreement with experimental values (R2 = 0.996). The experimental results and statistical analysis show that all operating parameters influence individually and interactively the sorption yields response. The optimum conditions for maximizing sorption yield were calculated as [YB]0 = 30 mg/L, [sorbent]0 = 0.1 g/250 mL, and pH 6, respectively. In addition to this, the sorption process studied is best described by the pseudo‐second‐order kinetic model. Langmuir sorption isotherm gave a satisfactory fit of the equilibrium data. The maximum sorption capacity is 130 mg YB/g shoe soles waste. Results from this study suggest that shoe soles waste is an effective sorbent for the removal of YB from aqueous solutions. © 2018 American Institute of Chemical Engineers Environ Prog, 38: S412–S421, 2019 [ABSTRACT FROM AUTHOR]

This study investigated the elaboration of novel porous absorbent granules by mixing powdered hydroxyapatite, metakaolin, sodium metasilicate, polyethylene glycol, and sodium dodecyl sulfate (SDS), an anionic surfactant. The effect of sodium dodecyl sulfate (SDS) was then studied by introducing it as a powder to the powdered mixture or dissolved into the granulation fluid. Characterization of the granules indicated that the incorporation of SDS dissolved in the granulation fluid into the G-PEG granules improved their specific surface area (97.9 m 2 /g) and porosity, resulting in a synergistic increase in the adsorption of crystal violet and methylene blue dyes compared to G-PEG granules and hydroxyapatite or metakaolin geopolymer alone. Moreover, the granules exhibited satisfactory compressive strength of 0.81 MPa, making them suitable for large-scale adsorption columns. Finally, the regeneratiοn prοcess οf the granules was modeled and optimized by using surface response methodology based on Box-Behnken design. The granules cοuld be regenerated fοr eight cycles under οptimum cοnditiοns οf acetic acid cοncentratiοn οf 0.72 mοl/L, a temperature οf 323 K, and a cοntact time οf 173.22 min, withοut a significant lοss in the adsοrptiοn capacity οr degradatiοn οf the granules. These results suggest that the pοrοus granules prepared in this study have pοtential tο be used in industrial wastewater treatment., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Onthophagus (Furconthophagus) shaykh Montanaro Ziani, new species (Coleoptera: Scarabaeidae: Onthophagini), until now confused with Onthophagus (Furconthophagus) aethiopicus dOrbigny, 1902, is described, illustrated, and compared with morphologically similar taxa. The phylogenetic relationships between the new species and the Palaearctic Onthophagus (Furconthophagus) furcatus (Fabricius, 1781) are briefly discussed.

There is an increasing need for rapid, reliable, non-invasive, and inexpensive mass testing methods as the global COVID-19 pandemic continues. Detection dogs could be a possible solution to identify individuals infected with SARS-CoV-2. Previous studies have shown that dogs can detect SARS-CoV-2 on sweat samples. This study aims to establish the dogs' sensitivity (true positive rate) which measures the proportion of people with COVID-19 that are correctly identified, and specificity (true negative rate) which measures the proportion of people without COVID-19 that are correctly identified. Seven search and rescue dogs were tested using a total of 218 axillary sweat samples (62 positive and 156 negative) in olfaction cones following a randomised and double-blind protocol. Sensitivity ranged from 87% to 94%, and specificity ranged from 78% to 92%, with four dogs over 90%. These results were used to calculate the positive predictive value and negative predictive value for each dog for different infection probabilities (how likely it is for an individual to be SARS-CoV-2 positive), ranging from 10-50%. These results were compared with a reference diagnostic tool which has 95% specificity and sensitivity. Negative predictive values for six dogs ranged from ≥98% at 10% infection probability to ≥88% at 50% infection probability compared with the reference tool which ranged from 99% to 95%. Positive predictive values ranged from ≥40% at 10% infection probability to ≥80% at 50% infection probability compared with the reference tool which ranged from 68% to 95%. This study confirms previous results, suggesting that dogs could play an important role in mass-testing situations. Future challenges include optimal training methods and standardisation for large numbers of detection dogs and infrastructure supporting their deployment., Competing Interests: The authors have declared that no competing interests exist.

Cholestatic liver diseases including primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) are associated with active hepatic fibrogenesis, which can ultimately lead to the development of cirrhosis. However, the exact relationship between the development of liver fibrosis and the progression of cholestatic liver disease remains elusive. Periductular fibroblasts located around the bile ducts seem biologically different from hepatic stellate cells (HSCs). The fibrotic events in these clinical conditions appear to be related to complex crosstalk between immune/inflammatory mechanisms, cytokine signalling, and perturbed homeostasis between cholangiocytes and mesenchymal cells. Several animal models including bile duct ligation (BDL) and the Mdr2-knockout mice have improved our understanding of mechanisms underlying chronic cholestasis. In the present review, we aim to elucidate the mechanisms of fibrosis in order to help to identify potential diagnostic and therapeutic targets.

The onthophagine fauna of the Arabian Peninsula is reviewed. New data from public and private collections are given. The total number of Onthophagini known from the Peninsula now stands at 30 species, without taking into account dubious records, belonging to seven genera. Of these 30 species, three (Onthophagus aethiopicus d'Orbigny, 1902, O. falsus Gillet, 1925 and O. frontalis Raffray, 1877) are reported for the first time from the Arabian Peninsula, six species (Digitonthophagus eucatta Génier in Génier Moretto, 2017, Onthophagus aethiopicus d'Orbigny, 1902, O. brittoni Paulian, 1948, O. falsus Gillet, 1925, O. rugulipennis Fairmaire, 1887, and O. trapezicornis d'Orbigny, 1902) are new records from Saudi Arabia, three (D. eucatta, O. aethiopicus and O. frontalis) are new from Yemen and five (O. bicolor Raffray, 1877, O. latipennis d'Orbigny, 1898, O. nitidulus Klug, 1856, O. quadriarmatus Fairmaire 1892 and O. sellatus Klug, 1845) are new from Oman. Furthermore, Onthophagus infuscatus Klug, 1845 is recorded from Djibouti for the first time. For all the treated species a general distribution, literature citations and eventual unpublished records are provided. A new synonymy (Onthophagus saudiensis Frey, 1962 under O. sticticus Harold, 1867) is proposed. Most of the species were recorded from locations in southern Saudi Arabia, Oman and Yemen, south Tropic of Cancer. Yemen and Saudi Arabia have the highest species numbers, hosting the richest fauna with 24 and 23 species, respectively. The majority of the Onthophagini fauna (73.33 %) has Afrotropical and Afrotropical-Palaearctic affinities, while the Palaearctic and Oriental-Palaearctic species are both represented by 6.66 %. The four Arabian endemisms represent the 13.33 % of the whole fauna. Lastly, a dichotomous key for the identification of Arabian onthophagine species is provided and a redescription of Onthophagus brittoni is supplied.

In nucleotide excision repair (NER), damage recognition by XPC-hHR23b is described as a critical step in the formation of the preincision complex (PInC) further composed of TFIIH, XPA, RPA, XPG, and ERCC1-XPF. To obtain new molecular insights into the assembly of the PInC, we analyzed its formation independently of DNA damage by using the lactose operator/repressor reporter system. We observed a sequential and ordered self-assembly of the PInC operating upon immobilization of individual NER factors on undamaged chromatin and mimicking that functioning on a bona fide NER substrate. We also revealed that the recruitment of the TFIIH subunit TTDA, involved in trichothiodystrophy group A disorder (TTD-A), was key in the completion of the PInC. TTDA recruits XPA through its first 15 amino acids, depleted in some TTD-A patients. More generally, these results show that proteins forming large nuclear complexes can be recruited sequentially on chromatin in the absence of their natural DNA target and with no reciprocity in their recruitment., (© 2014 Ziani et al.)

UV-induced DNA damage causes repression of RNA synthesis. Following the removal of DNA lesions, transcription recovery operates through a process that is not understood yet. Here we show that knocking-out of the histone methyltransferase DOT1L in mouse embryonic fibroblasts (MEF(DOT1L)) leads to a UV hypersensitivity coupled to a deficient recovery of transcription initiation after UV irradiation. However, DOT1L is not implicated in the removal of the UV-induced DNA damage by the nucleotide excision repair pathway. Using FRAP and ChIP experiments we established that DOT1L promotes the formation of the pre-initiation complex on the promoters of UV-repressed genes and the appearance of transcriptionally active chromatin marks. Treatment with Trichostatin A, relaxing chromatin, recovers both transcription initiation and UV-survival. Our data suggest that DOT1L secures an open chromatin structure in order to reactivate RNA Pol II transcription initiation after a genotoxic attack., Competing Interests: The authors have declared that no competing interests exist.

S-100B protein is selectively synthesized by glial cells, and is released in biological fluids after acute brain damage. We analyzed initial levels and evolution of plasma S-100B protein concentrations after resuscitated cardiopulmonary arrest (CPA). S-100B levels were determined in 27 subjects at the time of CPA (H0) then 12, 24 and 48 h after resuscitation. Initial levels of S-100B and kinetics revealed that: 1) 95% the of subjects with a concentration of protein S-100B greater than 0.80 microg/L at H0 did not survive; 2) 62% of subjects with a concentration of protein S-100B lower than 0.80 microg/L at H0 survived; 3) 100% of subjects with a protein S-100B level lower than 0.80 microg/L at H0 and whose evolution kinetics of S-100B levels showed a decrease survived; 4) 100% of the subjects whose S-100B levels increased from H12 died. In summary, this study suggests that the threshold of 0.80 microg/L for S-100B plasma levels at H0 could be predictive for the outcome of the CPA, when associated with the kinetic study of S-100B plasma concentration.

Clinical laboratories shall have a perfect control of "in vitro diagnostic medical devices" to ensure the quality of their analytical results. This introductory presentation to a serie of documents of recommendations tackles the different standards of metrology concerning the requirements to reference materials, metrological traceability, metrological confirmation, management of measurement as well as uncertainty of measurement. The standards concerning clinical laboratories are then succinctly described., (Copyright John Libbey Eurotext 20003.)