Search

The Miyaura borylation reaction enables the direct synthesis of boronates, a valuable partner in Suzuki-Miyaura coupling reactions. These C-C coupling reactions provide one of the most efficient methods for the construction of C-C bonds and are widely used in transition metal-catalyzed organic chemistry. However, analyses of these boronic acid/ester products and their derivatives are rarely discussed. In this communication, a sensitive and selective liquid chromatography method has been validated for the purity determination of a boronic ester intermediate where significant sample preparation challenges were observed. An efficient in-situ derivatization was implemented which consisted of a hydrolysis to the boronic acid derivative while simultaneously poisoning any residual active palladium. The HPLC analysis was performed on an Zorbax XDB-C18 (150 mm x 4.6 mm) 3.5 µm column utilizing water/acetonitrile gradient elution with an acidic modifier of 0.5 % trifluoroacetic acid at a flow rate of 1.0 mL/min. The detection was performed at the wavelength of 254 nm, and the retention time of the boronic ester was around 4.9 min. The proposed method was validated to ICH Q2 standards and included such parameters as specificity, system precision, accuracy/reproducibility, linearity, LOD/LOQ and solution stability.

Background A supraclavicular brachial plexus nerve block provides analgesia for the shoulder, arm, and hand; however, the maximum safe duration for a continuous infusion remains controversial. A novel continuous peripheral nerve block (CPNB) technique combining the Lateral, Intermediate, and Medial femoral cutaneous nerves (termed the ‘LIM’ block) to provide analgesia to the lateral, anterior, and medial cutaneous areas of the thigh while preserving quadriceps strength will also be described in detail here. Case We present a complex case in which simultaneous utilization of an unilateral supraclavicular CPNB (5 weeks) and bilateral LIM CPNB (5 days) are successfully performed to provide analgesia for a traumatic degloving injury resulting in multiple surgeries. Conclusions The analgesic plan in this case study eliminated previous episodes of opioid-induced delirium, facilitated participation in recovery, and removed concerns for respiratory depression and chronic opioid use in a patient at particular risk for both issues.

Abstract It is unclear if the exaggerated exercise pressor reflex observed in peripheral arterial disease (PAD) patients facilitates Oxygen (O2) transport during presymptomatic exercise. Accordingly, this study compared O2 transport between PAD patients and healthy controls during graded presymptomatic work. Seven PAD patients and seven healthy controls performed dynamic plantar flexion in the bore of a 3T MRI scanner. Perfusion, T2* (an index of relative tissue oxygenation), and SvO2 (a measure of venous oxygen saturation) were collected from the medial gastrocnemius (MG) during the final 10 seconds of each stage. Blood pressure was also collected during the final minute of each stage. As expected, the pressor response to presymptomatic work (4 kg) was exaggerated in PAD patients compared to controls (+14 mmHg ± 4 and +7 mmHg ± 2, P ≤ 0.034). When normalized to changes in free water content (S0), T2* was lower at 2 kg in PAD patients compared to controls (−0.91 Δms/ΔAU ± 0.3 and 0.57 Δms/ΔAU ± 0.3, P ≤ 0.008); followed by a greater increase in perfusion at 4 kg in the PAD group (+18.8 mL/min/100g ± 6.2 vs. −0.21 mL/min/100g ± 3.2 in PAD and controls, P ≤ 0.026). Lastly, SvO2 decreased at 4 kg in both groups (−13% ± 4 and −2% ± 4 in PAD and controls, P ≤ 0.049), suggesting an increase in O2 extraction in the PAD group. Based on these findings, O2 transport appears to be augmented during graded presymptomatic work in PAD patients, and this may be partially mediated by an exaggerated pressor response.

The increasing use of renewable energy sources in place of conventional generation units is leading to a reduction in onshore inertia and to the development of offshore wind park grids connected by multiple high-voltage direct current (HVDC) connections to the onshore alternating current (AC) grid. For AC-side meshed offshore grids with voltage-source converter (VSC) and diode rectifier unit (DRU) HVDC connections towards onshore grids, this study focuses on the energetic feasibility of synthetic inertia (SI) and primary control reserve (PCR) contributions triggered locally at the onshore converters of both connection types. To this end, the obstacles preventing contributions for VSC HVDC connections and the mechanisms allowing contributions for DRU HVDC connections are identified first. Based on these findings, the article proposes an enhancement of the offshore HVDC converter controls that is continuously active and allows locally triggered onshore contributions at all onshore HVDC converters of both connection types without using communication and requiring only minimal system knowledge. Additional simulations confirm that, although the enhancement is continuously active, the operational performance of the offshore HVDC converter controls for normal offshore grid operation and its robustness against offshore AC-side faults are not affected.

Previous studies have found that C turnover is bound to hotspots of microbial activity. The objective of this study was to analyze the effects of pure energy substrate (glucose), nutrient (mineral N or P) and combined substrate and nutrient (glucose + N, glucose + P, sterile DOC, artificial root exudate extract) additions to enzyme activity inside and outside hotspots as a proxy for microbial C turnover in a subsoil. By means of different substrate and nutrient additions, we tested how the limitations of our site were distributed on a small scale and depth-dependently to contribute to an increase in knowledge of subsoil mechanistics. The study site is a sandy Dystric Cambisol under an over 100-year-old beech forest stand in Lower Saxony, Germany. Forty-eight undisturbed soil samples from two depth increments (15–27 cm and 80–92 cm) of three profiles were sprayed homogeneously with easily available C, N and P sources to investigate the impacts of substrates and nutrients on three enzyme activities (acid phosphatase, β-glucosidase and N-acetylglucosaminidase) by using the soil zymography approach. Comparisons of upper and lower subsoils showed significantly fewer and smaller hotspots in the lower subsoil but with a high degree of spatial variation in comparison to the upper subsoil. Different patterns of enzyme distribution between upper and lower subsoil suggest microbial communities with a lower diversity are found in deeper soil regions of the site. Both substrate and nutrient additions stimulated enzyme activities significantly more outside the initial hotspots than within. Because of this, we conclude that microorganisms in the initial hotspots are less limited than in the surrounding bulk soil. Changes in enzyme activities owing to both substrate and nutrient addition were stronger in the lower subsoil than in the upper subsoil, showing differences in limitations and possible changes in microbial community structure with increasing depth. The results of our study emphasize the need to consider spatial factors in microbial turnover processes, especially in lower subsoil regions where stronger substrate and nutrient limitations occur.

One of the most important goals in vehicle acoustics is to describe the NVH behavior of a vehicle at sound pressure level using simulation models at an early stage of development. Different simulation models and methods are used for this purpose. To balance the advantages and disadvantages of the different methods, it is important to combine the simulation models. For the virtual description of the road booming noise behavior of a vehicle passing a rough road, we use a multibody simulation model excited with the elevation profile of the road in the time domain. To calculate the sound pressure inside the vehicle, the internal chassis forces of the multibody simulation model are combined with a finite element body model including the air cavity inside the cabin. The methodology for combining the chassis forces and body transfer functions to calculate the sound pressure is first validated using test data and then applied to the simulation data. The correlation of the calculated sound pressure based on test data (ρ=0.96) and based on simulation data (ρ=0.90) compared to a microphone measurement is very high.

For investigating influences of vehicle components on the acoustic comfort at low frequencies, e.g., the booming noise behavior of a vehicle, building a whole car simulation model is useful. To reduce the model’s complexity and to save resources in the validation process, we first identify relevant components before building the model. Based on previous studies, we focus on the vehicle’s body and the rear axle. In this paper, we analyze which axle and body elements are crucial for describing road booming noise. For this purpose, we use impact measurements to examine noise transfer functions of the body and a vibro-acoustical modal analysis to identify coupled modes between the body’s structure and the interior cavity. For investigating relevant force paths from the rear axle to the body, we used a chassis test bench. We identify the main transmission paths of road booming noise and highlight which axle and body components have an influence on them. Mainly the rear axle in its upright direction in combination with a rigid body movement of the rear tailgate coupled with the first longitudinal mode of the airborne cavity causes road booming noise. Furthermore, the rear axle steering, the active roll stabilization and the trim elements of the vehicle’s body are essential to describe road booming noise. The results can be used to set priorities in the validation of individual axle and body components for future simulation models. We found that the ventilation openings, the front seats, the headliner, and the cockpit of a vehicle have little influence on its noise transfer functions from the rear axle connection points to the driver’s ear between 20 and 60 Hz.

Multi-faceted stresses of social, environmental, and economic nature are increasingly challenging the existence and sustainability of our societies. Cities in particular are disproportionately threatened by global issues such as climate change, urbanization, population growth, air pollution, etc. In addition, urban space is often too limited to effectively develop sustainable, nature-based solutions while accommodating growing populations. This research aims to provide new methodologies by proposing lightweight green bridges in inner-city areas as an effective land value capture mechanism. Geometry analysis was performed using geospatial and remote sensing data to provide geometrically feasible locations of green bridges. A multi-criteria decision analysis was applied to identify suitable locations for green bridges investigating Central European urban centers with a focus on German cities as representative examples. A cost-benefit analysis was performed to assess the economic feasibility using a case study. The results of the geometry analysis identified 3249 locations that were geometrically feasible to implement a green bridge in German cities. The sample locations from the geometry analysis were proved to be validated for their implementation potential. Multi-criteria decision analysis was used to select 287 sites that fall under the highest suitable class based on several criteria. The cost-benefit analysis of the case study showed that the market value of the property alone can easily outweigh the capital and maintenance costs of a green bridge, while the indirect (monetary) benefits of the green space continue to increase the overall value of the green bridge property including its neighborhood over time. Hence, we strongly recommend light green bridges as financially sustainable and nature-based solutions in cities worldwide.

ABSTRACT The Ouchterlony double immunodiffusion assay is a serological technique used in the detection of antibodies and antigens for diagnostic purposes and also used in immunology laboratory courses as a common teaching assay where students observe the geometrical precipitation line patterns that form in the agarose, elucidating degrees of homology between antigens. In this classical technique, students must wait several hours to days to obtain results when protein antigens and antibodies are used. Furthermore, these proteins degrade over time if not frozen or stored in the refrigerator and are the most expensive consumables of the laboratory exercise. In this study, inexpensive and commonly used inorganic ionic salt solutions that are stable and can be stored at room temperature for several years were used to mimic antigens and antibodies. The precipitation lines started to form in the agarose plates after 15 min and fully developed within an hour, showing different geometrical precipitation patterns and spur formations that could be identified by students as full identity, partial identity, and nonidentity between the simulated (inorganic) antigens. Students conducting this exercise in a combined lecture and laboratory immunology course were able to finish the exercise as well as record and discuss results within class time, and tvhey showed increased interest in the laboratory exercise and had a better understanding of antibody-antigen reactions. Thus, this simulated laboratory experiment is an inexpensive, safe, and fast exercise that allows students to observe precipitations reactions of the Ouchterlony assay within the class session time.

Peridynamics describes the nonlinear interactions in spatially extended Hamiltonian systems by nonlocal integro-differential equations, which can be regarded as the natural generalization of lattice models. We prove the existence of solitary traveling waves for super-quadratic potentials by maximizing the potential energy subject to both a norm and a shape constraint. We also discuss the numerical computation of waves and study several asymptotic regimes.

Specific climate adaptation and resilience measures can be efficiently designed and implemented at regional and local levels. Climate and environmental databases are critical for achieving the sustainable development goals (SDGs) and for efficiently planning and implementing appropriate adaptation measures. Available federated and distributed databases can serve as necessary starting points for municipalities to identify needs, prioritize resources, and allocate investments, taking into account often tight budget constraints. High-quality geospatial, climate, and environmental data are now broadly available and remote sensing data, e.g., Copernicus services, will be critical. There are forward-looking approaches to use these datasets to derive forecasts for optimizing urban planning processes for local governments. On the municipal level, however, the existing data have only been used to a limited extent. There are no adequate tools for urban planning with which remote sensing data can be merged and meaningfully combined with local data and further processed and applied in municipal planning and decision-making. Therefore, our project CoKLIMAx aims at the development of new digital products, advanced urban services, and procedures, such as the development of practical technical tools that capture different remote sensing and in-situ data sets for validation and further processing. CoKLIMAx will be used to develop a scalable toolbox for urban planning to increase climate resilience. Focus areas of the project will be water (e.g., soil sealing, stormwater drainage, retention, and flood protection), urban (micro)climate (e.g., heat islands and air flows), and vegetation (e.g., greening strategy, vegetation monitoring/vitality). To this end, new digital process structures will be embedded in local government to enable better policy decisions for the future.

El presente trabajo tiene como objetivo establecer una metodología para el análisis de riesgo de equipos y sistemas productivos, así como identificar aquellos activos sujetos al proceso de validación. Se proporciona un conjunto de instrucciones que describen detalladamente los pasos a seguir para realizar el cronograma de validación con bases al riesgo residual. El estudio se realizó en el Centro Nacional de Investigaciones Científicas de Cuba, dirección de producción. El trabajo se basa en la implementación de la norma IEC 60812, análisis de los modos de fallo, efectos y criticidad (AMFEC). De conjunto con esta norma se utilizarán otros documentos indispensables para su aplicación como son la serie de normas IEC 60300-3-1 e IEC 61025. Entre los principales resultados se obtuvo el mapa de riesgo de la empresa y las acciones de control implementadas una vez identificado el riesgo residual. Estos resultados permitieron establecer el período mínimo indispensable para la validación de los sistemas tecnológicos de la empresa.

Antimicrobial resistance (AMR) is a global concern, pertaining not only to human health but also to the health of industry and the environment. AMR research has traditionally focused on genetic exchange mechanisms and abiotic environmental constraints, leaving important aspects of microbial ecology unresolved. The genetic and ecological aspects of AMR, however, not only contribute separately to the problem but also are interrelated. For example, mutualistic associations among microbes such as biofilms can both serve as a barrier to antibiotic penetration and a breeding ground for horizontal exchange of antimicrobial resistance genes (ARGs). In this review, we elucidate how species interactions promote and impede the establishment, maintenance, and spread of ARGs and indicate how management initiatives might benefit from leveraging the principles and tools of community ecology to better understand and manipulate the processes underlying AMR.

The health institutions have gained experience in managing their processes. For many the key to success lies in human resource management. Companies require personnel, and while more appropriate is the staff, its effi ciency will be greater. With the present article, we intend to provide a proceeding that supports the functions of the maintenance department at a hospital, under the criterion of determine the necessary staff, to carry out the maintenance tasks. Several factors are combined, highlighting, workload derived from the annual maintenance plan and the time available for department employees. The results obtained, permitted the identifi cation of the necessary staff to carry out the planned preventive maintenance actions at the at Children's Hospital Juan Manuel Marquez.

El proceso de validación se puede definir como la técnica mediante la cual se estable evidencia documentada, con alto grado de aseguramiento, de que un proceso específico proporciona en forma consistente un producto que cubre con las especificaciones predeterminadas y sus atributos de calidad. Identificar cuáles son los activos que se someterán al proceso de validación es una tarea prioritaria para cualquier empresa que implemente un Sistema de Gestión de la Calidad, lo cual repercute de manera directa en el éxito de cualquier empresa. Como consecuencia de esto en septiembre de 2014, se diseñó un procedimiento en el departamento de Aseguramiento de la Calidad, dirección de Producción, CNIC, con el OBJETIVO de determinar aquellos equipos o sistemas de apoyo auxiliar que serán sometidos al proceso de validación. Para darle cumplimiento a nuestro objetivo el MÉTODO utilizado se basa en la combinación de técnicas de riesgos tradicionales como son los métodos comparativos, diagramas lógicos de fallas, estudios de riesgo y operatividad, análisis de modos de falla y efectos, y otros. Como RESULTADO se obtuvo un procedimiento general para la aplicación de la técnica de criticidad, la cual denominamos HAZID (HAZardIDentification), basado en el análisis de riesgos. Como CONCLUSIÓN fundamental se obtiene un criterio de partida para justificar la inclusión de un equipo o sistema al proceso de validación.