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In this paper the reliability verification in a measurement system of passive components is presented, the passive components measured are integrated varactors. The measurement system used for the characterization of the varactors consists of the HP8719ES Vector Network Analyzer. To calibrate the measurement system, the short-open-load-through (SOLT) was used. The varactors have been designed with measurement structures in order to use the Cascade ACP40 GSG microprobes. The de-embedding process is used to move the measurement reference plane from the calibration point (probe tips) to the DUT (Device Under Test). For this work, it was used the Four Step De -embedding method but after making the necessary measurements the method has been simplified by not taking into account the coupling between signals due to tits very low value. Also, the characterization of the connections leads has not been done using the test structures but using the design rules. Due to the measurement system introduces uncertainty in the varactor measure, is necessary design some tests in order to calculate the error. In this paper these tests are defined. [ABSTRACT FROM PUBLISHER]

Traditionally, freight wagon technology has lacked digitalization and advanced monitoring capabilities. This article presents recent advancements in freight wagon digitalization, covering the system's definition, development, and field tests on a commercial line in Sweden. A number of components and systems were installed on board on the freight wagon, leading to the intelligent freight wagon. The digitalization includes the integration of sensors for different functions such as train composition, train integrity, asset monitoring and continuous wagon positioning. Communication capabilities enable data exchange between components, securely stored and transferred to a remote server for access and visualization. Three digitalized freight wagons operated on the Nässjo-Falköping line, equipped with strategically placed monitoring sensors to collect valuable data on wagon performance and railway infrastructure. The field tests showcase the system's potential for detecting faults and anomalies, signifying a significant advancement in freight wagon technology, and contributing to an improvement in freight wagon digitalization and monitoring. The gathered insights demonstrate the system's effectiveness, setting the stage for a comprehensive monitoring solution for railway infrastructures. These advancements promise real-time analysis, anomaly detection, and proactive maintenance, fostering improved efficiency and safety in the domain of freight transportation, while contributing to the enhancement of freight wagon digitalization and supervision.

A new experimental approach has been developed to study the distribution of local electrostatic potential around specific protons in biologically important molecules. The approach is the development of a method denoted as "spin label/spin probe," which was proposed by one of us (. Mol. Biol. 6:498-507). The proposed method is based upon the quantitative measurement of the contribution of differently charged nitroxide probes to the spin lattice relaxation rate (1/T1) of protons in the molecule of interest, followed by calculation of local electrostatic potential using the classical Debye equation. In parallel, the theoretical calculation of potential distribution with the use of the MacSpartan Plus 1.0 program has been performed. Application of the method to solutions of simple organic molecules (aliphatic and aromatic alcohols, aliphatic carboxylates (propionate anion), and protonated ethyl amine and imidazole) allowed us to estimate the effective potential around the molecules under investigation. These were found to be in good agreement with theoretically expected values. This technique was then applied to zwitterionic amino acids bearing neutral and charged side chains (glycine, lysine, histidine, and aspartic acid). The reliability of the general approach is proved by the data presented in this paper. Application of this new methodology can afford insight into the biochemical significance of electrostatic effects in biological systems.

A 32-year-old man developed panhypopituitarism and diabetes insipidus shortly after sustaining a head injury. Hormonal investigation showed that basal prolactin levels were moderately elevated the first two years after the accident, but later returned to normal. There was no rise in prolactin after administration on chlorpromazine, and the response to thyrotropin-releasing hormone was attenuated. Basal luteinizing hormone and follicle-stimulating hormone levels were low and there was no change after administration of luteinizing-hormone-releasing hormone. There was also no growth hormone elevation following arginine infusion. On the other hand, there was a normal but delayed elevation of thyrotropin in response to thyrotropin-releasing hormone. Appropriate stimulation tests showed normal responsiveness of the thyroid, adrenals and testes. These findings are compatible with an injury to the pituitary stalk, damaging the neurohypophyseal tract and affecting the blood supply to the pituitary gland.