A direct synthetic route to allyl sulfides from cyclic Morita–Baylis–Hillman alcohols

p-TsOH-mediated the direct α-substitution of cyclic Morita–Baylis–Hillman alcohols with aliphatic and aromatic thiols in refluxing THF. The reaction proceeded with complete α-regioselectivity and provided the corresponding allyl sulfides in moderate to good yields.     

Enhancing speech intelligibility in reverberant spaces by a speech features distributions dependent pre-processing

In this paper, we deal with a pre-processing based on speech envelope modulation for intelligibility enhancement in reverberant large dimension public enclosed spaces. In fact, the blurring effect due to reverberation alters the speech perception in such conditions. This phenomenon results from the masking of consonants by the reverberated tails of the previous vowels. This is particularly accentuated for elderly persons suffering from presbycusis. The proposed pre-processing is inspired from the steady-state suppression technique which consists in the detection of the steady-state portions of speech and the multiplication of their waveforms with an attenuation coefficient in order to decrease their masking effect. While the steady-state suppression technique is performed in the frequency domain, the pre-processing described in this paper is rather performed in the temporal domain. Its key novelty consists in the detection of the speech voiced segments using a priori knowledge about the distributions of the powers and the durations of voiced and unvoiced phonemes. The performances of this pre-processing are evaluated with an objective criterion and with subjective listening tests involving normal hearing persons and using a set of nonsense Vowel–Consonant–Vowel syllables and railway station vocal announcements.     

Modified insulator semiconductor electrode with functionalized nanoparticles for Proteus mirabilis bacteria biosensor development

The development of enzymatic sensors for biological purposes such as biomedicine, pharmacy, food industry, and environmental toxicity requires the purification step of the enzyme. To prevent the loss of the enzyme activity, a new strategy is held in order to immobilize the bacteria. It will constitute the biological sensing element leading to a high operational stability and multiple adaptations to various conditions such as temperature, pH and ionic strength changes. In this work we describe the development of a urea biosensor by immobilizing Proteus mirabilis bacteria onto an insulator–semiconductor electrode on functionalized Fe₃O₄ nanoparticles (NPs), using cationic, Poly (allylamine hydrochloride) then anionic, Poly (sodium 4-styrenesulfonate) polyelectrolytes, BSA (serum bovin albumin), and glutaraldehyde as a cross-linking agent. The response of P. mirabilis to urea addition is evaluated in homogeneous and heterogeneous phases. Before the immobilization step, the activity of urease produced from the P. mirabilis bacteria was attempted using the ion ammonium selective electrodes (ISEs). Adhesion of the bacteria cells on IS electrodes have been studied using contact angle measurements.After immobilization of the bacteria, on the (Si/SiO₂/Si₃N₄) and (Si/SiO₂) substrates, the relationship between the evolution of the flat band potential ?V_FB and the urea concentration is found to be linear for values ranging from 10^? 2 M to 10^? 5 M.     

In Vitro Rescue of the Bile Acid Transport Function of ABCB11 Variants by CFTR Potentiators

ABCB11 is responsible for biliary bile acid secretion at the canalicular membrane of hepatocytes. Variations in the ABCB11 gene cause a spectrum of rare liver diseases. The most severe form is progressive familial intrahepatic cholestasis type 2 (PFIC2). Current medical treatments have limited efficacy. Here, we report the in vitro study of Abcb11 missense variants identified in PFIC2 patients and their functional rescue using cystic fibrosis transmembrane conductance regulator potentiators. Three ABCB11 disease-causing variations identified in PFIC2 patients (i.e., A257V, T463I and G562D) were reproduced in a plasmid encoding an Abcb11-green fluorescent protein. After transfection, the expression and localization of the variants were studied in HepG2 cells. Taurocholate transport activity and the effect of potentiators were studied in Madin–Darby canine kidney (MDCK) clones coexpressing Abcb11 and the sodium taurocholate cotransporting polypeptide (Ntcp/Slc10A1). As predicted using three-dimensional structure analysis, the three variants were expressed at the canalicular membrane but showed a defective function. Ivacaftor, GLP1837, SBC040 and SBC219 potentiators increased the bile acid transport of A257V and T463I and to a lesser extent, of G562D Abcb11 missense variants. In addition, a synergic effect was observed when ivacaftor was combined with SBC040 or SBC219. Such potentiators could represent new pharmacological approaches for improving the condition of patients with ABCB11 deficiency due to missense variations affecting the function of the transporter.     

The instructional benefits of dynamic visualizations in the acquisition of basketball tactical actions

Recent studies exploring the effects of dynamic visualizations on learning compared with static visualizations have yielded mixed results. Procedural motor learning is one of the few fields in which dynamic representations have shown to be effective. Many of the studies have suggested that this advantage is mainly due to the activation of the “mirror‐neuron system.” This study explores this explanation in physical education domain and analysed the effects of instructional media (video vs. photographs), showing tactical actions in basketball, on learning outcomes (i.e., game understanding and game performance), cognitive load (i.e., mental effort invested and estimated difficulty), and attitudes (i.e., attention, enjoyment, engagement, and challenge) in secondary school students. For all of the indicators, the results show that learning from video was more effective than learning from photographs. These findings have implications for the effective design of instructional media and provide confirmation of the superiority of video for teaching tactical actions involving the entire body.     

Purification and characterization of trypsin from the viscera of sardine (Sardina pilchardus)

Trypsin from the viscera of Sardina pilchardus was purified by fractionation with ammonium sulphate, heat treatment and Sephadex G-100 gel filtration with a ninefold increase in specific activity and 9% recovery. The molecular weight of the enzyme was estimated to be 25,000 Da on SDS–PAGE. This enzyme showed esterase-specific activity on Nα-benzoyl-l-arginine ethyl ester (BAEE). The purified enzyme was inhibited by benzamidine, a synthetic trypsin inhibitor, and phenylmethylsulphonyl fluoride (PMSF) a serine-protease inhibitor, but was not inhibited by the β-mercaptoethanol. The optimum pH and temperature for the enzyme activity were pH 8.0 and 60 °C, respectively. The relative activity at pH 9.0 was 95.5% and the enzyme showed pH stability between 6.0 and 9.0. The N-terminal amino acid sequence of the first 12 amino acids of the purified trypsin was IVGGYECQKYSQ. S. pilchardus trypsin, which showed high homology to other fish trypsins, had a charged Lys residue at position 9, where Pro or Ala are common in fish trypsins. The enzyme was strongly inhibited by Zn²⁺ and Cu²⁺.     

Combined Post-harvest Treatments for Improving Quality and Extending Shelf-Life of Minimally Processed Broccoli Florets (<Emphasis Type="Italic">Brassica oleracea var. italica</Emphasis>)

Broccoli is an important source of many nutritional and bioactive compounds. However, its shelf-life is very short due to physicochemical losses and microbiological degradation. This study was undertaken to implement treatments that could improve the quality of ready-to-eat (RTE) broccoli during storage by evaluating the effect of pre-treatment with calcium chloride (CaCl₂) and alginate coating on the physicochemical and microbial properties of RTE broccoli. Broccoli florets were pre-treated with three different concentrations of CaCl₂ (1, 2.5, and 4 g L^?1), then coated with an alginate formulation (13 g L^?1) and stored at 4 °C for 24 days. Texture, color, weight loss, respiration rate, and total mesophilic flora (TMF) counts were evaluated at days 0, 3, 7, 14, and 24 of storage. The obtained results in this study showed that combining pre-treatment with calcium and alginate coating led to reducing the weight loss and respiration rate of broccoli, maintaining its color and texture as well as extending its shelf-life by 6 days. These results not only allowed reducing post-harvest losses resulting in the loss of the product but also have a major impact on the environment and resources involved in the production process.