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Determining compositional trends among individual minerals is key to understanding the thermodynamic conditions under which they formed and altered, and is also essential to maximizing the scientific value of small extraterrestrial samples, including returned samples and meteorites. Here we report the chemical compositions of Fe-sulfides, focusing on the pyrrhotite-group sulfides, which are ubiquitous in chondrites and are sensitive indicators of formation and alteration conditions in the protoplanetary disk and in small Solar System bodies. Our data show that while there are trends with the at.% Fe/S ratio of pyrrhotite with thermal and aqueous alteration in some meteorite groups, there is a universal trend between the Fe/S ratio and degree of oxidation. Relatively reducing conditions led to the formation of troilite during: (1) chondrule formation in the protoplanetary disk (i.e., pristine chondrites) and (2) parent body thermal alteration (i.e., LL4 to LL6, CR1, CM, and CY chondrites). Oxidizing and sulfidizing conditions led to the formation of Fe-depleted pyrrhotite with low Fe/S ratios during: (1) aqueous alteration (i.e., CM and CI chondrites), and (2) thermal alteration (i.e., CK and R chondrites). The presence of troilite in highly aqueously altered carbonaceous chondrites (e.g., CY, CR1, and some CM chondrites) indicates they were heated after aqueous alteration. The presence of troilite, Fe-depleted pyrrhotite, or pyrite in a chondrite can provide an estimate of the oxygen and sulfur fugacities at which it was formed or altered. The data reported here can be used to estimate the oxygen fugacity of formation and potentially the aqueous and/or thermal histories of sulfides in extraterrestrial samples, including those returned by the Hayabusa2 mission and due to be returned by the OSIRIS-REx mission in the near future.

BACKGROUND Cutibacterium acnes (C. acnes) is associated with infection following shoulder and spine surgery due to follicular pore concentrations in these anatomic regions. It has been established that it can form biofilms on surgical implant materials, which may contribute to its role in perioperative infection, but its behavior of early colonization on those materials is not yet well understood. PURPOSE The purpose of this study was to evaluate the time to adherence and subsequent biofilm formation of C. acnes in the first 24 hours on implant materials commonly used in spinal surgery. STUDY DESIGN We compared the colonization and behavior of C. acnes over time when applied to five commonly used spine implant materials – polyether ether ketone (PEEK), cobalt chromium (CC), stainless steel (SS), titanium, and titanium alloy. METHODS C. acnes was applied onto the samples of PEEK, CC, SS, titanium, and titanium alloy, and allowed to adhere for periods of 4, 8, 12, 16, and 20 hours. Nonadherent bacteria were then washed from the samples. These samples were then allowed to continue incubating for a total 24 hours. Scanning electron microscopy and confocal laser scanning microscopy were used to visualize all samples for the presence and quantification of C. acnes adherence at each time period. Subsequent transition to biofilm formation on these samples was assessed via scanning electron microscopy at each time period. RESULTS The PEEK specimens exhibited the highest amount of surface biological burden in the first 24 hours compared with the other materials, which displayed little or no adherence. Rapid biofilm formation first observed at 8 hours of allowed adhesion on PEEK, whereas no significant biofilm formation was seen on the other materials during the observed time period. CONCLUSIONS Although C. acnes is known to have a slow proliferation rate, the results of this investigation demonstrate that it can rapidly adhere to and form a biofilm on PEEK. These data suggest that the use of PEEK implants placed during spinal surgery may facilitate early intraoperative colonization, and subsequent infection, compared with metallic implants. CLINICAL SIGNIFICANCE The findings of this study suggest that PEEK may prove to be problematic as a choice of implant material in cases were C. acnes infection is a possibility.

Sulfide minerals occur in many types of extraterrestrial samples and are sensitive indicators of the conditions under which they formed or were subsequently altered. Here we report that chemical and petrographic analyses of Fe,Ni sulfides can be used to determine the metamorphic type of the host LL chondrite, and constrain their alteration conditions. Our data show that the major- and minor-element compositions of the pyrrhotite-group sulfides (dominantly troilite) and pentlandite vary with degree of thermal metamorphism experienced by their host chondrite. We find that Fe,Ni sulfides in LL3 chondrites formed during chondrule cooling prior to accretion, whereas those in LL4 to LL6 chondrites formed during cooling after thermal metamorphism in the parent body, in agreement with previous work. High degrees of shock (i.e., ≥S5) caused distinct textural, structural, and compositional changes that can be used to identify highly shocked samples. Distinct pyrrhotite-pentlandite textures and minerals present in Appley Bridge (LL6) suggest that they cooled more slowly and therefore occurred at greater depth(s) in the host parent body than those of the other metamorphosed LL chondrites studied here. Sulfides in all LL chondrites studied formed under similar sulfur fugacities, and the metamorphosed LL chondrites formed under similar oxygen fugacities. The data reported here can be applied to the study of other LL chondrites and to sulfides in samples of asteroid Itokawa returned by the Hayabusa mission in order to learn more about the formation and alteration history of the LL chondrite parent body.

Bisphenol AF (BPAF) is in the body mainly metabolized to the corresponding bisphenol AF glucuronide (BPAF-G). While BPAF-G is not commercially available, enzyme-assisted synthesis of BPAF-G using the human recombinant enzyme UGT2A1, purification of BPAF-G by solid phase extraction and semi-preparative HPLC and chemical characterization of BPAF-G by NMR and LC-MS/MS were performed and are described here. Furthermore, BPAF glucuronidation kinetics with the UGT enzymes that showed the highest glucuronidation activity in previous studies (i.e hepatic UGTs 1A3, 2B7, and 2B17, intestinal UGT 1A10 and UGT 2A1 that is present in airways) was performed and data is presented. Hepatic enzymes exhibited high affinities toward BPAF, while extrahepatic UGTs 2A1 and 1A10 showed the high v(max), values (3.3 and 3.0 nmol/min/mg, respectively). To understand molecular interactions of BPA, BPAF and BPAF-G with ligand biding sites of several nuclear receptors, molecular modeling was performed and data on the binding modes of BPAF, BPA, and BPAF-G in the ligand-binding sites of nuclear receptors are presented. This article is related to "Endocrine activities and adipogenic effects of bisphenol AF and its main metabolite" (Skledar et al., 2019). (C) 2018 The Authors. Published by Elsevier Inc.

Background : The COVID-19 pandemic affected healthcare systems worldwide. Predictive models developed by Artificial Intelligence (AI) and based on timely, centralized and standardized real world patient data could improve management of COVID-19 to achieve better clinical outcomes. The objectives of this manuscript are to describe the structure and technologies used to construct a COVID-19 Data Mart architecture and to present how a large hospital has tackled the challenge of supporting daily management of COVID-19 pandemic emergency, by creating a strong retrospective knowledge base, a real time environment and integrated information dashboard for daily practice and early identification of critical condition at patient level. This framework is also used as an informative, continuously enriched data lake, which is a base for several on-going predictive studies. Methods : The information technology framework for clinical practice and research was described. It was developed using SAS Institute software analytics tool and SAS® Vyia® environment and Open-Source environment R ® and Python ® for fast prototyping and modelling. The included variables and the source extraction procedures were presented. Results : The Data Mart covers a retrospective cohort of 2634 patients with SARS-CoV-2 infection. People who died were older, had more comorbidities, reported more frequently dyspnea at onset, had higher d-dimer, C-reactive protein and urea nitrogen. The dashboard was developed to support the management of COVID-19 patients at three levels: hospital, single ward and individual care level. Interpretation : The COVID-19 Data Mart based on integration of a large collection of clinical data and an AI-based integrated framework has been developed, based on a set of automated procedures for data mining and retrieval, transformation and integration, and has been embedded in the clinical practice to help managing daily care. Benefits from the availability of a Data Mart include the opportunity to build predictive models with a machine learning approach to identify undescribed clinical phenotypes and to foster hospital networks. A real-time updated dashboard built from the Data Mart may represent a valid tool for a better knowledge of epidemiological and clinical features of COVID-19, especially when multiple waves are observed, as well as for epidemic and pandemic events of the same nature (e. g. with critical clinical conditions leading to severe pulmonary inflammation). Therefore, we believe the approach presented in this paper may find several applications in comparable situations even at region or state levels. Finally, models predicting the course of future waves or new pandemics could largely benefit from network of DataMarts.

This study was developed to investigate parents' perceptions and attitudes towards distance learning in response to many school's closures due to the COVID-19 pandemic. This research uses a qualitative approach. The research subjects consisted of parents of elementary school students in the City of Gunungsitoli, determined by purposive sampling technique, totaling twenty-four people. The data were collected using semi-structured interview techniques and analyzed using thematic analysis techniques. This study shows that distance learning or learning from home in a research context takes the form of online and offline learning. For parents, the learning approach implemented during the COVID-19 pandemic emergency must be lived and supported in the absence of other options. Although parents do not have negative perceptions, distance learning has increased the burden on parents or families economically, psychologically, and socially. The lack of parental involvement and support in children's learning process at home is generally due to the lack of time and parents' inability to become teachers for their children. Actions to accompany and support children's learning process at home are carried out to provide internet packages, help children master the material, and participate in completing assignments or tests given by the teacher. The surprising finding from this study is the decline in learning motivation and cognitive abilities of children. Parents hope that distance learning is not extended in the remainder of the 2020/2021 school year so that children can study again at educational institutions.

Micro-Electro-Mechanical Systems (MEMS) gyroscopes are inertial sensors for the measurement of angular rates. They have a variety of applications from consumer electronics to drones and the need of stability against environmental fluctuations, such as temperature, is a key factor in order to avoid expensive calibration procedures. Frequency Modulation (FM) has been recently proposed as an innovative working principle for MEMS gyroscopes and as the desired solution in terms of stability against environmental fluctuations. In this paper, the FM working principle is formalized for the three-axial case for the first time and the governing equations are derived both in the idealized case of a point-mass gyroscope and in the real case of a distributed-mass gyroscope. Moreover, the mechanical structure of the first three-axial MEMS FM gyroscope is proposed and studied. Preliminary experimental measurements prove the validity of both the model and the simulations results employed during the design process. The proposed structure overcomes lots of the constraints of the surface micromachining fabrication processes and represents an important step towards the development of a new class of MEMS gyroscopes.

To investigate the origin of fine-grained rims around chondrules (FGRs), we compared presolar grain abundances, elemental compositions and mineralogies in fine-grained interstitial matrix material and individual FGRs in the primitive CO3.0 chondrites Allan Hills A77307, LaPaz Icefield 031117 and Dominion Range 08006. The observation of similar overall O-anomalous (∼155 ppm) and C-anomalous grain abundances (∼40 ppm) in all three CO3.0 chondrites suggests that they all accreted from a nebular reservoir with similar presolar grain abundances. The presence of presolar silicate grains in FGRs combined with the observation of similar estimated porosity between interstitial matrix regions and FGRs in LAP 031117 and ALHA77307, as well as the identification of a composite FGR (a small rimmed chondrule within a larger chondrule rim) in ALHA77307, all provide evidence for a formation of FGRs by accretion of dust grains onto freely-floating chondrules in the solar nebula before their aggregation into their parent body asteroids. Our study also shows systematically lower abundances of presolar silicate grains in the FGRs than in the matrix regions of CO3 chondrites, while the abundances of SiC grains are the same in all areas, within errors. This trend differs from CR2 chondrites in which the presolar silicate abundances are higher in the FGRs than in the matrix, but similar to each other within 2σ errors. This observation combined with the identification of localized (micrometer-scaled) aqueous alteration in a FGR of LAP 031117 suggests that the lower abundance of presolar silicates in FGRs reflects pre-accretionary aqueous alteration of the fine-grained material in the FGRs. This pre-accretionary alteration could be due to either hydration and heating of freely floating rimmed chondrules in icy regions of the solar nebula or melted water ice associated with 26 Al-related heating inside precursor planetesimals, followed by aggregation of FGRs into the CO chondrite parent-body.

The initial moisture condition of recycled concrete aggregates has a great influence on the fresh and hardened state of concrete. Water compensation is generally proposed with the aim of avoiding changes in the effective water-to-cement ratio and preventing water transfer from the mix to the porous aggregates. However, full compensation of water absorption of aggregates is not recommended. The issue remains unclear for recycled aggregates in general, and for fine recycled concrete aggregates (FRCA) in particular. Moreover, the water absorption of FRCA shows large variations depending on the determination method, making the value for the effective water-to-cement ratio even more uncertain. This paper entails a revision on the knowledge of the FRCA absorption kinetics and its consideration in mix proportioning. Own experimental results and data from the literature are analysed to show the relationship between the compressive strength of concrete and both the effective and total water-to-cement ratios. Compressive strength seems to be notably affected by how FRCA water absorption is taken into account in mix proportioning.

A petrographic method is proposed to semi-quantify the content of particles with reactive phases in fine recycled concrete aggregates (FRCA) affected by the alkali-silica reaction and the residual mortar (RM) adhered to them. This method is compared to the image analysis method. Quartered FRCA samples are studied by three petrographers, and the results are compared. Finally, the potential reactivity of the samples is evaluated by the accelerated mortar bar test (AMBT). According to the AMBT and petrographic method, the samples are qualified as potentially reactive, with a low degree of reactivity. The method is easy to perform and fast (compared to image analysis), but the results obtained by three petrographers show some differences that can mainly be attributed to the visual estimation of RM. Although more studies are needed to verify the effectiveness of the proposed method, the implemented technique shows great potential to semi-quantify reactive components in FRCA particles.

Rural houses are recently built using confined masonry walls. The concrete beam and column confining the wall are usually considered to resist lateral loads, such as earthquake load. The Indonesian code requires reinforcement of 12 mm diameter in each corner of the beam and column with 8 mm diameter of stirrups. Such houses are usually termed of non-engineered structures, i.e buildings which the strength is not technically calculated but is established by the communities based on their experiences. This research was aimed to relate the in plane lateral ground acceleration and the resulting lateral displacement on the top of the wall at the first fundamental frequency. As the wall occasionally breaks at certain lateral drift ratio (H/V ratio), therefore, a prediction of the maximum lateral ground acceleration of the wall due to earthquake shake may also be established. Two wall specimens were made of local masonries with dimensions of 3m x 3m and 0.15 m thick. Lateral loads were applied in several stages and ambient vibrations of the two accelerometers, mounted on the base and on the top of the wall, were also recorded in stages. The maximum lateral force prediction, calculated using allowable lateral ground acceleration, was closely approaching the experiment result and numerical calculation.

This paper presents a new metamaterial plate (metaplate) made by a periodic repetition of ‘frame-springs-mass’ systems for vibration isolation. Numerical studies and experimental measurements demonstrate that the proposed structure show a complete 3D phononic bandgap in the low-frequency range. In the numerical computation of the transmission diagram, the self-weight gravity, the material damping, the geometry of the metaplate and different boundary conditions are considered. A prototype of the proposed metaplate, made of Polyamide, is fabricated by means of additive manufacturing and experimentally tested. The measured transmission diagram is in good agreement with numerical predictions, thus proving the proposed design and promoting potential applications such as low-frequency vibration isolation and stress wave mitigation.

Human DNA topoisomerase II is one of the major targets in anticancer therapy, however ATP-competitive inhibitors of this target have not yet reached their full potential. ATPase domain of human DNA topoisomerase II belongs to the GHKL ATPase superfamily and shares a very high 3D structural similarity with other superfamily members, including bacterial topoisomerases. In this work we report the discovery of a new chemotype of ATP-competitive inhibitors of human DNA topoisomerase IIα that were discovered through screening of in-house library of ATP-competitive inhibitors of bacterial DNA gyrase and topoisomerase IV. Systematic screening of this library provided us with 20 hit compounds. 1,2,4-Substituted N-phenylpyrrolamides were selected for a further exploration which resulted in 13 new analogues, including 52 with potent activity in relaxation assay (IC50 = 3.2 µM) and ATPase assay (IC50 = 0.43 µM). Cytotoxic activity of all hits was determined in MCF-7 cancer cell line and the most potent compounds, 16 and 20, showed an IC50 value of 8.7 and 8.2 µM, respectively.