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Erbium doping (0.1, 0.15, 0.20 at % Er) markedly increases the photosensitivity and photoluminescence (PL) intensity of GaS crystals. Most likely, erbium substitutes on the gallium site. Irradiation with low gamma doses increases the photosensitivity and PL intensity of the crystals, broadens their PL spectrum, and shifts the PL peaks to longer wavelengths. It seems likely that the radiation-induced recombination centers consist of gallium vacancies and erbium atoms. The concentration of such defect complexes depends on the gamma dose. [ABSTRACT FROM AUTHOR]

Membrane-based processes are taking a more and more prominent position in the search for sustainable and energy-efficient gas separation applications. It is known that the separation performance of pure polymers may significantly be improved by the dispersion of suitable filler materials in the polymer matrix, to produce so-called mixed matrix membranes. In the present work, four different organic cages were dispersed in the poly(ether ether ketone) with cardo group, PEEK-WC. The m-xylyl imine and furanyl imine-based fillers yielded mechanically robust and selective films after silicone coating. Instead, poor dispersion of p-xylyl imine and diphenyl imine cages did not allow the formation of selective films. The H2, He, O2, N2, CH4, and CO2 pure gas permeability of the neat polymer and the MMMs were measured, and the effect of filler was compared with the maximum limits expected for infinitely permeable and impermeable fillers, according to the Maxwell model. Time lag measurements allowed the calculation of the diffusion coefficient and demonstrated that 20 wt % of furanyl imine cage strongly increased the diffusion coefficient of the bulkier gases and decreased the diffusion selectivity, whereas the m-xylyl imine cage slightly increased the diffusion coefficient and improved the size-selectivity. The performance and properties of the membranes were discussed in relation to their composition and morphology. [ABSTRACT FROM AUTHOR]

• Commercial and waste carbon-based fillers are compared in lime-based mixes. • Waste fillers increase the compressive strength of lime-based mixes. • Waste fillers decrease lime-based mixes water suction and increase VOCs adsorption. • Waste fillers increase electrical conductivity and EMI SE of lime-based mixes. • Waste fillers are a sustainable and cheap alternative for multifunctional mixes. Carbon-based fillers from industrial wastes and commercial ones were compared to improve the properties of lime-based mixes. As commercial fillers, graphene nanoplatelets and activated carbon were used, whereas as industrial wastes a char obtained by the gasification of biomasses and a used foundry sand were chosen. Carbon-based wastes were found to be a good cost-effective alternative to commercial carbon based fillers to increase the compressive strength (of about 25%) and to reduce water capillary absorption (of about 50%) thanks to the paste refinement; to enhance depollution capacity (of about 25%) and increase both electrical conductivity (up to 65%) and electromagnetic shielding effectiveness (of about 6%) of the hardened compounds thanks to the carbon content. [ABSTRACT FROM AUTHOR]

• Electrical impedance is used as NDT for concrete health status assessment. • Three concrete compositions were subjected to accelerated degradation tests. • Wenner's method is used for measuring electrical impedance in AC configuration. • Electrical impedance decreases with water/chlorides penetration. • Low-clinker cements help in increasing detectability of aggressive agents. This paper discusses the electrical impedance behaviour, measured according to the Wenner's method, of three different concrete mixes during accelerated degradation tests. Being a first attempt to move from laboratory to in-field applications targeted to long-term monitoring, the same electrode array configuration and set-up (AC current at 10 kHz) is used. Results show that electrical impedance decreases down to 24% in capillary water absorption tests, 77% and 86% in salt-spray chamber and wet/dry cycles with 3.5% NaCl solution, respectively. The two new low-clinker cements adopted seem to improve the measurement sensitivity towards contaminants ingress with respect to the commercial one (reference). [ABSTRACT FROM AUTHOR]

Introduction: placental mesenchymal dysplasia (PMD) is a rare placental anomaly characterized by placentomegaly and grapelike vesicles which resemble molar pregnancy. Case: we report the case of 33-year-old woman (1-gravid) who visited our clinic at 11 weeks of gestation due to a suspected molar pregnancy. Ultrasound examination showed an enlarged placenta with multiple vesicular lesions. Maternal human chorionic gonadotropin level was normal and chorionic villus sampling showed a normal male karyotype (46 XY). The fetus exhibited no specific anomalies and fetal growth was normal during pregnancy with no signs of fetal suffering. At 31 weeks, the pregnancy ended owing to intrauterine fetal death (IUFD). The patient delivered a normal-sized male fetus (1800 g) with no definite anomalies. A pathological examination led to a diagnosis of placental mesenchymal dysplasia. Conclusion: in the presence of placental ultrasound anomalies with no other sign of fetal suffering, the pregnancy should be considered at risk and, therefore, should be monitored carefully including the option of hospitalization. [ABSTRACT FROM AUTHOR]

• OPC, CSA, and AAC mortars are compared at the same strength class. • AAC mortars are less rigid but shrink more than CSA and CEM ones. • AAC mortars are more permeable and sulfates resistant than CEM and CSA ones. • AAC and CSA mortars absorb less water than CEM ones. There is an increasing interest towards the development of alternative binders for the manufacture of sustainable mortars and concretes. Ordinary Portland cement (OPC) is the most commonly used material in construction, even if its production process is highly polluting. Both calcium sulfoaluminate (CSA) and alkali-activated cements (AAC) are potential alternative binders to be used in both structural (R3 class, with R c ≥ 25 MPa) and non-structural applications (R1 and R2 classes, with R c ≥ 10 MPa and R c ≥ 15 MPa, respectively) according to UNI EN 1504-3. This paper reports the hydration mechanisms and the evolution of porosity of OPC-, CSA- and AAC-based binders. The properties of fresh and hardened mortars, belonging to the above-mentioned mechanical strength classes, were evaluated and compared with particular emphasis on durability properties in terms of capillary water absorption, drying shrinkage, and resistance to sulfate attack. The results show that CSA-based mortars exhibit the lowest drying shrinkage due to their highest elasticity modulus. AAC mortars are characterized by the highest water vapor permeability and the lowest capillary water absorption for the highest presence of large pores (>3000 nm). [ABSTRACT FROM AUTHOR]

The paper aims to provide a comprehensive study on the compositional optimization of high-conductive multifunctional fiber-reinforced cement mortars (FRCMs). Therefore, the effects of three different fiber types: virgin carbon fibers (VCFs), recycled carbon fibers (RCFs), and brass-plated steel fibers (BSFs), added at a broad range of concentrations, as 0.05%, 0.1%, 0.2%, 0.4%, 0.8%, 1.2%, and 1.6% by volume, on the mechanical, electrical and durability properties of FRCMs have been compared. The results showed that RCFs increase the flexural and tensile splitting strength up to 100%, whereas BSFs improve the compressive strength by 38%. Moreover, the fibers decrease both the capillary water absorption and the drying shrinkage by 39%. Electrical conductivity tests show that RCFs decrease the electrical resistivity of mortars up to one order of magnitude, in addition to a percolation threshold between 0.1 and 0.2 vol%. [ABSTRACT FROM AUTHOR]

We aimed to screen for connexin26 gene (GJB2) mutations associated with autosomal recessive non-syndromic neurosensory deafness (NSRD) in a general risk population. Screening for the most common connexin26 gene mutations was offered to all women undergoing a second-trimester amniocentesis for fetal karyotype analysis in our Center. After rapid DNA extraction from amniotic fluid, PCR amplification was performed and products analysed to detect mutations of GJB2 gene by a sequencing technique. In particular, we searched for the 20 most frequently reported mutations (out of the approximately 90 so far described) and for which there are commercially available tests. From a total of 4819 consecutive amniotic fluids examined, the following five different heterozygous mutations were detected: 35delG in 80 cases, 167delT in 3 cases and 1 occurrence of each of the following mutations: M34T, 35insG and W77R. From these data, a prevalence of 1 : 56 (1.78%) for the heterozygous condition can be estimated in the Mediterranean general risk population. The striking predominance of 35delG mutation is confirmed. In addition, we detected a homozygous 35delG mutation condition in a foetus of no risk parents. In this case, the early diagnosis permitted prompt application of an acoustic prosthesis allowing for cochlear implantation in due time, with significant improvement of the prognosis. In a general risk population, a carrier status for congenital deafness can be observed in 1 : 56 (1.78%) amniotic fluids; this is mostly due to the presence of a 35delG mutation of the connexin26 gene. Occasional identification of homozygous states, although rare, allows the best therapeutic approach. Copyright © 2003 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The increased interest of consumers in probiotic foods requires a deeper knowledge on the possible interactions with drugs, because their pharmacological properties could be modified. In this context, these studies are relevant for drugs such as acenocoumarol, whose dosage must be controlled due to, among other factors, food-drug interactions. Acenocoumarol is an oral anticoagulant with a narrow therapeutic range. The aim of the present research is to evaluate, in vitro , the effect of bifidobacteria on acenocoumarol. The drug was incubated with Bifidobacterium bifidum CIDCA 5310 or Bifidobacterium adolescentis CIDCA 5317 in MRS broth at 37°C for 24 h in anaerobic conditions. The effect of incubation with sterilized spent culture supernatants (SSCS) was also evaluated. Analysis by RP-HPLC showed that both bifidobacterial strains reduced the area of the acenocoumarol peak and two new peaks were evidenced. In addition, a decrease in the intensity of the bands at 1650, 1390 and 1110/cm was observed in the FTIR spectroscopic determinations. Moreover, a new band appeared at 1720/cm. No effect on the drug was observed when incubation was performed with SSCS. The present study showed a significant change in the concentration of the anticoagulant after incubation with bifidobacteria and results are compatible with biomodification of the drug due to enzymatic activity of bifidobacteria. [ABSTRACT FROM AUTHOR]

The possibility of recycling mixed colour waste glass as it is for manufacturing decorative architectural mortars, has been investigated. In mortars, the 0-33-66-100% of calcareous gravel volume has been replaced with recycled glass cullets, with no other inorganic addition. To mitigate the possible alkali-silica reaction, mixes with a hydrophobic admixture were also compared. The obtained results show that the replacement of calcareous gravel with glass cullets of similar grain size distribution permits to reduce the dosage of the superplasticizer admixture to obtain the same workability of fresh mortar; it does not affect significantly the mechanical performances, the water vapour permeability and the capillary water absorption but it reduces significantly the drying shrinkage deformation. The used recycled glass is classified as no reactive in terms of alkali-silica reaction neither in water nor in NaOH solution following the parameters of the current normative, even in the absence of the hydrophobic admixture. The hydrophobic admixture further delays the expansion trigger but not the speed of its propagation. [ABSTRACT FROM AUTHOR]

Purpose: The aim of our study is to evaluate taste changes in patients affected by solid tumors not involving oral cavity within the first month of standard chemotherapy. Methods: In this monocentric, prospective, cohort study, we enrolled patients treated at our institution for different types of solid tumors between February and July 2019. Taste cotton swabs assay was used to assess taste changes. Results: Thirty-one patients were enrolled and most of them had at least one change in taste. The taste that changed less was acid (42% of the population) whereas the one that changed the most was the perception of sweet (reduced in 35% of the population and increased in 45% of the population) and sour (reduced in 35% of the population). We did not find any statistical significant difference in terms of changes of taste and type of chemotherapy (emetogenic vs not, p > 0.05 for salty, sweet, bitter, and acid tastes). The type of primary tumor (breast vs GI-related) had a significant impact on perception of both salty (p = 0.0163) and acid (p = 0.0312) flavor. Furthermore, body mass composition assessed by BIA showed that obese patients had different changes in acid flavor vs non-obese patients (p = 0.04). This could not be proven when the assessment was made using BMI calculation. Conclusions: Our study suggests that type of primary tumor (GI vs breast) more than type of chemotherapy used could be relevant in determining changes in taste during chemotherapy. Individualized dietary strategies based on these reported data are suggested, as to optimize patients' management. [ABSTRACT FROM AUTHOR]

The research on systems able to perform controllable motions under external stimuli arises great interest in the scientific community. Over the years, a library of innovative devices has been produced, classified in different categories according to the molecular or supramolecular level of motion. This minireview aims to highlight some representative studies, in which organic cages are used as building blocks for mechanically interlocked molecules, and in which intramolecular motions are triggered by external input. However, the application of organic cages in the construction of molecular machines is hardly achieved. A good compromise must actually be reached, between flexibility and rigidity of the cage's framework for an effective control of the intra‐ and/or intermolecular motion in the final mechanical device. Our final goal is to stimulate researchers′ curiosity towards cage‐like molecules, so that they take on the challenge of converting a cage into a molecular machine. [ABSTRACT FROM AUTHOR]

In a seismic context, it is fundamental to deploy distributed sensor networks for Structural Health Monitoring (SHM). Indeed, regularly gathering data from a structure/infrastructure gives insight on the structural health status, and Artificial Intelligence (AI) technologies can help in exploiting this information to generate early warnings useful for decision-making purposes. With a perspective of developing a remote monitoring platform for the built environment in a seismic context, the authors tested self-sensing concrete beams in loading tests, focusing on the measured electrical impedance. The formed cracks were objectively assessed through a vision-based system. Also, a comparative analysis of AI-based and statistical prediction methods, including Prophet, ARIMA, and SARIMAX, was conducted for predicting electrical impedance. Results show that the real part of electrical impedance is highly correlated with the applied load (Pearson's correlation coefficient > 0.9); hence, the piezoresistive ability of the manufactured specimens has been confirmed. Concerning prediction methods, the superiority of the Prophet model over statistical techniques was demonstrated (Mean Absolute Percentage Error, MAPE < 1.00%). Thus, the exploitation of electrical impedance sensors, vision-based systems, and AI technologies can be significant to enhance SHM and maintenance needs prediction in the built environment. [ABSTRACT FROM AUTHOR]

Prosopis nigra , a sucrose-rich crop, was used to enzymatically synthesize fructo-oligosaccharides (FOS). The obtained products were used as stabilizing matrices during freeze-drying and storage of Lactobacillus delbrueckii subsp. bulgaricus CIDCA 333. The centesimal composition of P. nigra flour was firstly determined. FOS were synthesized using Viscozyme L as biocatalyst. The progress of the enzymatic reaction was monitored by HPLC and compared with a reaction carried out using equivalent concentrations of pure sucrose as substrate (control). Then, P. nigra containing or not the obtained FOS (P. nigra + FOS or P. nigra) were used as matrices for freeze-drying and storage of L. delbrueckii subsp. bulgaricus CIDCA 333. P. nigra flour was rich in simple sugars (sucrose and fructose), total dietary fiber, and polyphenols. The main products of synthesis were FOS with degrees of polymerization (DP) within 3 and 5, and these results were comparable with those of the controls. DP3 was the first product obtained, attaining the maximal production after 1.29 hours of synthesis. The maximal production of total FOS (DP3 + DP4 + DP5) was achieved after 2.57 hours, indicating that larger FOS (DP4, DP5) were produced from DP3. Glucose was obtained as secondary product, but with significantly lower V max and K f (maximal velocity for the production and constant for the formation) than DP3. Both P. nigra + FOS or P. nigra matrices stabilized the highly sensitive L. delbrueckii subsp. bulgaricus CIDCA 333 strain during freeze-drying and storage for up to 140 days at 4 °C, and were significantly better protectants than the controls of sucrose (p <0.05). The concomitant presence of prebiotics (FOS), antioxidants (polypyhenols) and lactic acid bacteria in the matrices provides a smart strategy to increase the value of this underutilized regional crop, turning it in an interesting ingredient potentially useful in the food industry. Unlabelled Image • P. nigra was used as substrate for the synthesis of FOS. • The kinetics for the production of the different FOS was investigated. • The obtained FOS were used to protect L. bulgaricus during freeze-drying/storage. • P. nigra and P. nigra + FOS were significantly better protectants than sucrose. • Results appear as a smart strategy to add value to P. nigra regional crop. [ABSTRACT FROM AUTHOR]

An abstract of the article "How the proportion of invasive prenatal diagnosis changed in 33,679 invasive procedures after the introduction of cfDNA," by C. Coco and colleagues is presented.

Highlights • Cotton shell ash can be used to synthesise metakaolin inorganic polymers. • Heating the ash at 850 °C for 1 h improves its reactivity. • The optimum K/Al ratio could not be determined from the reaction enthalpy. • The formation of kalsilite and zeolite K-F crystalline phases was observed. • Products' strengths increased with K/Al ratio to a maximum before slightly dropping. Abstract Inorganic polymers were synthesised using metakaolin and cotton shell ash as activator. In this way, the negative environmental impact of sodium or potassium silicate solutions as alkaline activators can be eliminated. Phase transformations investigated using FTIR suggested the formation of inorganic polymers through the shift of the most intense band from 1031 cm−1 in metakaolin to around 973 cm−1 in the final product and the absence of the band at 789 cm−1 in the latter. XRD results revealed the presence of kalsilite and zeolite K-F, which appear as hexagonal and elongated crystals in SEM. A maximum compressive strength of 36.7 MPa was obtained. Compressive strength values increased with increasing K/Al ratios and with the reduction of pore densities due to the formation of the amorphous inorganic polymer matrix as observed on the SEM micrographs. Cotton shell ash can thus be used as an alternative activator. [ABSTRACT FROM AUTHOR]

The aim of this work was to assess the role of mono- and oligosaccharides present in fructo-oligosaccharides (FOS) mixtures as protective agents during freeze-drying and storage of Lactobacillus delbrueckii subsp. bulgaricus CIDCA 333. Different FOS mixtures were enzymatically obtained from sucrose and further purified by removing the monosaccharides produced as secondary products. Their glass transition temperatures (T g ) were determined at 11, 22 and 33% relative humidity (RH). Bacterial cultures were freeze-dried in the presence of 20% w/v solutions of the studied FOS. Their protective effect during freeze-drying was assessed by bacterial plate counting, and by determining the lag time from growth kinetics and the uptake of propidium iodide (PI). Plate counting during bacterial storage at 4 °C, and 11, 22 and 33% RH for 80 days completed this rational analysis of the protective effect of FOS. Purification of FOS led to an increase of T g in all the conditions assayed. Microorganisms freeze-dried in the presence of non-purified FOS were those with the shortest lag times. Bacteria freeze-dried with pure or commercial FOS (92% of total FOS) showed larger lag times (8.9–12.6 h). The cultivability of microorganisms freeze-dried with non-purified FOS and with sucrose was not significantly different from that of bacteria before freeze-drying (8.74 ± 0.14 log CFU/mL). Pure or commercial FOS were less efficient in protecting bacteria during freeze-drying. All the protectants prevented membrane damage. The cultivability of bacteria freeze-dried with FOS decayed < 1 logarithmic unit after 80 days of storage at 11% RH. When storing at 22 and 33% RH, pure and commercial FOS were those that best protected bacteria, and FOS containing monosaccharides were less efficient. The effect of FOS on bacterial protection is the result of a balance between monosaccharides, sucrose and larger FOS in the mixtures: the smallest sugars are more efficient in protecting lipid membranes, and the larger ones favor the formation of vitreous states. [ABSTRACT FROM AUTHOR]

Fructo-oligosaccharides (FOS) are mixtures of oligosaccharides composed of fructose and glucose units. As their composition is determined by the synthesis conditions, the goals of this work were: (a) to engineer FOS of different composition by adjusting the sucrose concentration used as initial substrate; (b) to define partial least square (PLS) based-models to quantify all the sugars present in the reaction medium directly from the FTIR spectra. The yield of each reaction was calculated as the percentage of initial sucrose converted to each oligosaccharide, as monitored by HPLC. In parallel, the reactions were followed by FTIR. Six different PLS models aiming to determine the concentration of each carbohydrate present in the reaction medium were calibrated and independently validated. The means of predicted values fitted well to those obtained by HPLC. Determining FOS composition directly from the FTIR spectra represents a useful tool to monitor enzymatic synthesis, with strong impact at both an academic and an industrial level. [ABSTRACT FROM AUTHOR]

Two types of inulins of different composition were investigated in the glassy and in the crystalline states, at relative humidities within 11 and 97%. The melting and glass transition temperatures (Tm, Tg), and their crystallinity indexes (CI) were determined by modulated differential-scanning calorimetry (MDSC) and wide-angle X-ray scattering (WAXS), respectively. In parallel assays, Fourier transform-infrared spectroscopy (FTIR) coupled to principal component analysis (PCA) enabled a physical-chemical and structural characterization of samples, explaining 90% of the total variance. Finally, partial least square (PLS) models were defined to determine Tg, Tm, and CI directly from the FTIR spectra, using the MDSC and WAXS results as reference methods. In all cases, the mean of predicted values fitted very well those of the reference methods (R 2  > 0.961), thus supporting the use of the PLS models to investigate unknown samples. The robustness of the models underlines the usefulness of FTIR to easily determine physical-chemical parameters, otherwise requiring complex preparation of samples and prolonged times of analysis. [ABSTRACT FROM AUTHOR]

• An automated system for standard carbonation depth measurements is proposed. • Processing algorithm provides average and maximum carbonation depths. • Computer vision, image processing, and Convolutional Neural Networks are used. • Convolutional Neural Networks separate carbonated aggregates from paste. • The measurement system is challenged in terms of repeatability and reproducibility. This paper aims at discussing an automated measurement system for detecting carbonation depth in concrete sprayed with phenolphthalein. Image processing and Convolutional Neural Networks strategies are exploited to accurately separate the carbonated and non-carbonated areas and to remove those aggregates on the carbonation front that could bring to a wrong evaluation of the carbonation depth. Very strong correlation (R2 = 0.96) is found between results provided by the proposed approach and the method suggested by the EN 13295 standard. The expanded uncertainty (coverage factor k = 2) of this novel approach is 0.08 mm. ANOVA analysis performed in multi-operator tests proved that the highest source of uncertainty is the measurement system, which, on the other hand, is robust to changes in the operator performing the measurement. [ABSTRACT FROM AUTHOR]

The increase in concrete structures' durability is a milestone to improve the sustainability of buildings and infrastructures. In order to ensure a prolonged service life, it is necessary to detect the deterioration of materials by means of monitoring systems aimed at evaluating not only the penetration of aggressive substances into concrete but also the corrosion of carbon-steel reinforcement. Therefore, proper data collection makes it possible to plan suitable restoration works which can be carried out with traditional or innovative techniques and materials. This work focuses on building heritage and it highlights the most recent findings for the conservation and restoration of reinforced concrete structures and masonry buildings.