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Pseudomonas aeruginosa is a Gram-negative bacillus included among the six "ESKAPE" microbial species with an outstanding ability to "escape" currently used antibiotics and developing new antibiotics against it is of the highest priority. Whereas minimum inhibitory concentration (MIC) values against Pseudomonas aeruginosa have been used previously for QSAR model development, disk diffusion results (inhibition zones) have not been apparently used for this purpose in the literature, and we decided to explore their use in this sense. We developed multiple QSAR methods using several machine learning algorithms (Support vector classifier, K Nearest Neighbors, Random Forest Classifier, Decision Tree Classifier, AdaBoost Classifier, Logistic Regression, and Naive Bayes Classifier). The main descriptors used in building the models belonged to the families of adjacency matrix, constitutional descriptors, first highest eigenvalue of Burden matrix, centered Moreau-Broto autocorrelation, and averaged and centered Moreau-Broto autocorrelation descriptors. A total of 32 models were built, of which 28 were selected and stacked to create a meta-model. In terms of balanced accuracy, the best performance was provided by KNN, SVM and AdaBoost algorithms, but the ensemble method had slightly superior results in nested cross-validation.

Drug-induced liver injury (DILI) remains one of the challenges in the safety profile of both authorized and candidate drugs, and predicting hepatotoxicity from the chemical structure of a substance remains a task worth pursuing. Such an approach is coherent with the current tendency for replacing non-clinical tests with in vitro or in silico alternatives. In 2016, a group of researchers from the FDA published an improved annotated list of drugs with respect to their DILI risk, constituting &ldquo, the largest reference drug list ranked by the risk for developing drug-induced liver injury in humans&rdquo, (DILIrank). This paper is one of the few attempting to predict liver toxicity using the DILIrank dataset. Molecular descriptors were computed with the Dragon 7.0 software, and a variety of feature selection and machine learning algorithms were implemented in the R computing environment. Nested (double) cross-validation was used to externally validate the models selected. A total of 78 models with reasonable performance were selected and stacked through several approaches, including the building of multiple meta-models. The performance of the stacked models was slightly superior to other models published. The models were applied in a virtual screening exercise on over 100,000 compounds from the ZINC database and about 20% of them were predicted to be non-hepatotoxic.

The goal of this study was to validate an alternative method for determining in vivo acute toxicity using vegetal material instead of laboratory animals, starting from the phytobiological method known also as the Triticum technique. We set out to demonstrate that vegetal cells have similar sensitivity to some toxic agents as animal cells, in which case a statistical correlation could be established. A series of new compounds synthesized by the Romanian National Institute for Chemical Pharmaceutical Research and Development as potential β3 adrenergic receptors agonists were tested for their acute toxicity using classic animal exposure models, before investigating possible anti-diabetic and anti-obesity effects. We then determined whether similar conclusions might be reached exposing vegetal material to the same agents. We successfully demonstrated that plants are affected in a very similar way as animals when exposed to some potentially toxic agents, providing new possibilities for ending unethical animal experiments.

The paper reports on the design, fabrication, and characterization of a 7-layer SiO2-TiO2 colored coating for solar thermal façades. A combined theoretical and experimental approach was employed for designing the colored coating by using optical modeling and individual layers characterization, targeting for high solar transmittance and pronounced yellow-green reflected color. SiO2-TiO2 multilayers were deposited on glass and silicon substrates by using the reactive RF magnetron sputtering of stoichiometric oxide targets. The coatings were investigated by UV–Vis spectrophotometric methods for optical properties, surface profilometry, X ray reflectivity and SEM for the thickness of individual layers composing the multilayer and AFM for surface roughness. Hardness H, reduced modulus Er, and adhesion were determined by nanoindentation and scratch tests. The deposited colored glazing exhibited a prominent reflectivity peak of ~54% centered at 574nm, specific visible reflectance of ~45.39% and an integrated solar transmittance of about 80.3%. Its optical properties were preserved in the ambient for temperatures up to 200°C and the color was not modified for incidence angles up to 45°. H values of 7.18GPa, Er of 88.31GPa, H/Er ratio of about 0.081 and good scratch resistance up to 13mN were measured. Keywords: Multilayer design, Optical coatings, Colored glazing, Magnetron sputtering

It is currently recognized that an injudicious strategy about caries in the last decades has been not only focusing of research mostly in children, but also the narrow focusing on fluoride, because despite sufficient availability of fluoride in water and oral healthcare products, caries levels escalate steadily as people get older and caries remain a main public health issue to be settled. In the last two decades the scientific community intensified efforts of exploring other products for caries prevention, herbal products being one of these approaches. Preliminary evidence indicated that clinical trials for caries prevention with herbal products are heterogeneous in design, quality and products evaluated, we therefore performed a scoping review intended to explore the main characteristics of such clinical trials. From an initial collection of 1986 unique papers from different literature databases, 56 articles satisfied the inclusion and exclusion criteria. The species investigated, dosage forms, study designs, duration of intervention, controls, endpoints, quality of reporting, and risk of bias are discussed. Of the trials reviewed here, 85.71% reported positive results but given the methodological flaws and biases affecting them, it is difficult to conclude on the efficacy of those products based on the studies published thus far.

A variety of medicinal products have been associated with rash and normally this information should be available in the Summary of Product Characteristics (SmPCs). Our study aimed to investigate the frequency of rash as an adverse drug reaction, based on the information provided by SmPCs of 1,048 single active substances (international non-proprietary names) authorized in the United Kingdom. Data on rash frequency was collected from each SmPC using automated searches based on selected keywords. Data analysis was carried out using R, v. 3.4. We found that over 90% of the medicines used orally or by injection may be associated with rash as an adverse event, the most common classes being protein kinase inhibitors, anticancer medicinal products, monoclonal antibodies, biologicals, antivirals and retinoids, with high variations in rash frequency for products within the same class, but also for products with the same active substance. Analysis of SmPCs revealed the need to increase homogeneity in reporting rash frequency, by using Council for International Organizations of Medical Sciences classification, and Medical Dictionary for Regulatory Activities coding in a more standardized manner, and also the need to include more safety endpoints in clinical trials and to use better the safety results for publication and updating the SmPCs.

We report on the design, development, and testing of the high-power Laser Transmitter Assembly (LTA) supporting the Deep Space Optical Communications (DSOC) demonstration hosted on the Psyche Discovery class mission, due to launch in 2022. The DSOC project, under development by NASA’s Jet Propulsion Laboratory, will test space-to-ground high-bandwidth laser communications while en route to the Psyche-16 asteroid in the main asteroid belt, in what will be the longest range high rate optical communications link in history. The LTA is based on a master-oscillator power-amplifier optical architecture, using highly-efficient cladding-pumped amplification. The transmitter is designed to deliver average optical output powers

Central and Eastern European countries Romania and Moldova are rich in botanical and medicinal traditions. However, limited information is available about ethnobiological studies including use of medicinal plants in self-medication of minor illnesses. The aim of this study was to collect contemporary evidence about treatment options of the common cold and influenza with medicinal plants among pharmacy customers of two neighbouring countries: Romania and Republic of Moldova, including the self-proclaimed region Transnistria. A cross-sectional survey was undertaken in community pharmacies of Romania, Moldova and Transnistria in 2017. The pharmacy customers enrolled in the study completed a survey instrument evaluating perceived characteristics and action taken in case of common cold or influenza symptoms. A considerable proportion of the respondents used self-treatment options based on OTC medicines and/or medicinal plants. Survey respondents used professional (general practitioner, pharmacist) and non-professional (family and friends) information sources to learn more about medicinal plants. Medicinal plants were frequently used and considered effective in the treatment of the common cold and influenza. However, there are different use patterns of medicinal plants against the common cold and influenza among patients in Romania and Moldova. More common medicinal plants used in all three regions were lemon, raspberry and garlic, which were considered effective in monotherapy or in combination with non-prescription medicines.

SK-MEL-5 is a human melanoma cell line that has been used in various studies to explore new therapies against melanoma in different in vitro experiments. Based on this study we report on the development of quantitative structure-activity relationship (QSAR) models able to predict the cytotoxic effect of diverse chemical compounds on this cancer cell line. The dataset of cytotoxic and inactive compounds were downloaded from the PubChem database. It contains the data for all chemical compounds for which cytotoxicity results expressed by GI50 was recorded. In total 13 blocks of molecular descriptors were computed and used, after appropriate pre-processing in building QSAR models with four machine learning classifiers: Random forest (RF), gradient boosting, support vector machine and random k-nearest neighbors. Among the 186 models reported none had a positive predictive value (PPV) higher than 0.90 in both nested cross-validation and on an external dataset testing, but 7 models had a PPV higher than 0.85 in both evaluations, all seven using the RFs algorithm as a classifier, and topological descriptors, information indices, 2D-autocorrelation descriptors, P-VSA-like descriptors, and edge-adjacency descriptors as sets of features used for classification. The y-scrambling test was associated with considerably worse performance (confirming the non-random character of the models) and the applicability domain was assessed through three different methods.

The use of optical frequency combs (OFCs) for multi-heterodyne spectroscopy has enabled unprecedented measurement capabilities for spectroscopic sensing, including rapid acquisition speed, high resolution and high sensitivity1,2. Development of field deployable OFC sources that are widely tunable in the important chemical fingerprint region in the long-wavelength infrared (LWIR) is a major research challenge. In this paper, we report our recent efforts towards developing LWIR comb source for SILMARILS (Standoff ILluminator for Measuring Absorbance and Reflectance Infrared Light Signatures) program by IARPA. LGS has developed fiber optic sources producing spectral combs in the SWIR (1.52 to 1.56 μm and 1.7 to 2.0 μm) and in the LWIR (7.7 to 12.1 μm) regions. The spectral combs in the LWIR are generated by difference-frequency mixing one OFC centered around 1.54 μm with another OFC, whose center wavelength is tunable between 1.7 and 2.0 μm, in a nonlinear optical crystal. Average power of the generated LWIR is 1.2-12 mW and its instantaneous spectral breadth of the combs is > 80 cm-1, sufficiently broad to cover multiple molecular absorption peaks. We demonstrate standoff sensing of chemical targets having concentration as low as 12 μg/cm2 by measuring LWIR transflectance spectra using the comb source.

Many researchers perform different research in the area of ostheosznthesis metallic implants used in orthopedic surgery. The main goal of internal fixation is to achieve full operation until patient recovery. Although implants are intended to withstand until bone consolidation in some cases problems occur due to accelerate wear and corrosion processes. The aim of the present study was to determine the causes leading to adverse reactions of the surrounding tissues in case of three implants for osteosynthesis type plate-screw.

The aim of this paper is to determine causes of failure of orthopedic implants like intramedullary nail based on explants analysis and materials characterization. The clinical performance, corrosion characteristics and metallurgical properties of some retrieved titanium femoral nails have been examined. The macroscopic and the microscopic investigation of explants help us to describe the breaking mechanism and to identify the potential causes that led to implant failure.

A 1.9 μm hybrid silicon/III-V laser based on a wafer bonding technique is reported. The gain materials are InGaAs multiple quantum wells grown on InP substrate, with strain compensation between barriers and wells. The III-V wafer is bonded to a silicon-on-insulator wafer with processed silicon waveguides and transition tapers. Laser emission with a threshold current of 95 mA at room temperature and 45 mA at 5 °C is demonstrated.

GABRIELA LAURA ALMAJAN1*, STEFANIA FELICIA BARBUCEANU1, IOANA SARAMET1, MIHAELA DINU2, CRISTIAN VASILE DOICIN3,CONSTANTIN DRAGHICI4 1 Organic Chemistry Department, Faculty of Pharmacy, Traian Vuia Street 6, 020956, Bucharest, Romania 2 Pharmaceutical Botany Department, Faculty of Pharmacy, Traian Vuia Street 6, 020956, Bucharest, Romania 3 Manufacturing Engineering Department, Faculty of Engineering and Management of Technological Systems, Splaiul Independentei 313, Bucharest, Romania 4 C.D.Nenitescu Institute of Organic Chemistry, Romanian Academy, 202B Splaiul Independentei, 060023, Bucharest, Romania

We describe negative group index surface plasmons in nano-structured metallic gratings. The periods and amplitudes of silver gratings exhibiting negative group index, as well as the attenuation lengths of the negative-index surface waves, are derived.

We measure the phase dynamics and statistics of SOA-based wavelength conversion and XOR operation using linear optical sampling. We elucidate the role of the pattern dependent phase fluctuation in limiting the performance of XOR operation. (2 pages)

We report high coupling efficiencies from ridge waveguides to photonic crystal waveguides using photonic crystal waveguide tapers. Modified waveguide bends result in enhanced bend efficiencies and bandwidths. Experimental transmission curves agree quantitatively with calculated spectra.

The diffraction of ultrashort laser pulses from static gratings in photorefractive multiple quantum wells (PRQW) has been investigated for use as a diffractive optical elements in information processing systems with ultrashort laser pulses. The PRQW used in this experiment was specially designed to exhibit broad bandwidth. The desirable spectra of the diffracted pulses from the PRQW was observed experimentally. The bandwidth for one of the PRQW devices was 13 nm.

Room temperature pulsed lasing at 1.29 /spl mu/m in an optically pumped GaAsSb/GaAs quantum well VCSEL on a GaAs substrate is reported. This is the longest wavelength VCSEL reported in this material system.