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Background: Brucellosis is a zoonosis, caused by Brucella spp. which are small aerobic intracellular coccobacilli, localized in the reproductive organs of host animals, causing abortion and sterility. The diagnosis of this zoonosis is based on microbiological, serological or real time-polymerase chain reaction (RT-PCR) laboratory tests. Although the common microbiological and serological based assays have advantages, they are not able to solve the diagnosis problems. Aims: To overcome some of the limitations of present techniques, in this study, we developed an aptamer through whole-cell systematic evolution of Ligands by EXponential enrichment (SELEX) procedures to detect Brucella. Methods: We used mixture of Brucella melitensis and Brucella abortus as the target. In order to prepare the single-stranded DNA (ssDNA) aptamer, the DNA library was amplified with 5´-phosphorylated reverse primer and treated with lambda exonuclease. The SELEX procedure was performed by incubating the ssDNA pool with a bacterial suspension in a binding buffer. The selected procedures were monitored by flow cytometry using FITC-labelled forward primer. Aptamers with the highest binding affinity towards the target and the lowest to other strains were selected. Results: Two aptamers namely B20 and B21 showed significant binding affinity toward B. melitensis and B. abortus. The dissociation constant (Kd) for aptamers B20 and B21 was 40.179 ± 3.06 pM and 184.396 ± 465 pM, respectively. Conclusion: The isolated aptamers were able to identify B. melitensis and B. abortus with a remarkable binding efficiency and appropriated Kd in a picoMolar range and therefore can be good candidates in the development of any rapid assay test implanted on routine brucellosis diagnoses.

Background: Morbidity and mortality of preterm babies are important issues in perinatal medicine. In developed countries, preterm delivery is the cause of about 70% of mortality and 75% of morbidity in the neonatal period, respectively. Objective: The aim of this study was to determine the risk factors for preterm labor and the outcomes, in terms of perinatal mortality and morbidity at the time of discharge home, among preterm infants at less than 34 weeks gestation. Materials and Methods: A retrospective study was conducted and all infants with a gestational age of 24 to 33 weeks and 6 days who were born from November 1st, 2011 to March 31, 2012 were enrolled in this study. Results: From 1185 preterm infants were born during this period, 475 (40.08%) infants with less than 34 weeks gestational age were included in the study. Our study showed the major obstetrical risk factors for preterm labor were as follows: preeclampsia (21%), premature rupture of membranes (20.3%), abruption of placenta (10%), and idiopathic cases (48.7%). The neonatal mortality rate in less than 34 weeks was 9.05%. Significant perinatal morbidity causesd in less than 34 weeks were as follows: sepsis (46.94%), respiratory distress syndrome (41.47%), patent ductus arteriosus (21.47%), retinopathy of prematurity (3.57%), necrotizing entrocolitis (1.68%), intra-ventricular hemorrhage (9%), and broncho-pulmonary dysplasia (0.84%). Conclusion: Preterm birth is associated with adverse perinatal outcome. This situation needs to be improved by directing appropriately increased resources for improving prenatal health services and providing advanced neonatal care.

Increased urbanization as well as political and environmental aspects are leading to an increasing utilization of HVAC underground power cables instead of overhead lines (OHLs) in transmission grids. The insertion of mixed OHL-cable connections can give rise to technical challenges related to the occurrence of electromagnetic transients. More specifically, during switching operations high overvoltages can arise, in particular at the transition points between OHL and cable, and knowledge of their magnitudes is important information for safe operation of the connection. This paper discusses measurements, performed for the Dutch transmission system operator, based on open air capacitances picking up the electric fields from the line. For the open air sensors, the result at the end of the measuring cable is a differentiated voltage signal and the original waveform is restored by means of integration. Since the transported signal is integrated at the input of the measuring cabinet, interference pick-up is significantly reduced. The system is simple in terms of installation, does not require special HV components and has a large bandwidth with excellent electromagnetic compatibility (EMC) performance. However, since the sensors are open air, they also intercept field lines from the other phases, and possibly even from neighbouring circuits. Measurement decoupling is necessary, so methods to restore single-phase waveforms from switching events are discussed. Results from measurements, using the Differentiating/Integrating (D/I) technique, at a 380 kV mixed overhead line underground power cable connection obtained at a transition point and at a substation are presented and compared with PSCAD simulations. For switching transients the measurements confirm simulated overvoltage magnitudes to be reliable and within the safe margin of 2 pu.

TenneT, a leading European electricity transmission system operator (TSO) is planning to install a 3.4 km long underground superconducting 110 kV cable as part of the Dutch electricity grid, in the city of Enschede. HTS cables have already been demonstrated on a relatively small scale in other countries, but they are usually not part of the meshed high-voltage grid and the length of the relevant cable section generally does not exceed 1 km. In 2009, a 600-meter section of HTS cable was installed in New York, and in 2014 a 1-km long section was taken in operation in Essen, Germany to replace a 10 kV AC medium-voltage line. In the Supernet NL program, TenneT is working together with several leading knowledge institutes including University of Twente, Delft University of Technology, the Institute of Science and Sustain- able Development (IWO), HAN University of Applied Sciences and RH Marine. These institutes have been investigating control engineering aspects and the requirements the cable must meet. In the meantime, the tender process has been started which consists of two phases. In the fi rst phase (summer 2017) appropriate candidates are selected directly followed by a call for tender in August. Receipt of the best and fi nal offer is scheduled for the end of November. In the presentation, the project will be introduced and requirements will be discussed, specifi cally focusing on the cryogenic aspects.

There is an increased prevalence of maternal substance abuse during pregnancy in younger women in all socioeconomic classes and races. Our aim was to determine the prevalence and correlates of self-reported substance abuse among pregnant women and obstetric complications or neonatal outcomes in Iran. This retrospective cohort study is covering a five year period on medical records of pregnant women attending the maternity unit of four major hospitals (Mahdieh, Taleghani, Imam Hossein and Akbarabadi Hospitals). Women who reported using opium, heroin, crack, cannabis or methamphetamine were compared with women with no reported history of drug abuse for obstetric complications and prenatal morbidity and neonatal mortality. From 100,620 deliveries substance abuse was recorded for 519 women giving a prevalence of 0.5%. Opium was the most prevalent substance abused followed by crack (a mix of heroin and amphetamines). The exposed group had significantly more obstetric complications including preterm low birth weight and postpartum hemorrhage than the non-exposed group. The exposed group had significantly worse prenatal outcomes including more admissions to intensive care unit and higher infant mortality than the non-exposed group. None of the women in the exposed group was on methadone treatment at time of delivery. Risks of maternal and neonatal complications were increased in substance using pregnant women, especially preterm birth and low birth weight. We recommend a multidisciplinary team to provide methadone maintenance therapy for substance using pregnant women and urinary screen of all pregnant women presenting to hospital.

Godkänd; 2014; 20141209 (matbol)

On-line Partial Discharge (PD) detection and location systems for medium-voltage cables are at present being introduced in Dutch utilities and worldwide. The technical challenges now move from the development of the diagnostic technique itself to efficient implementation on alarge scale. In this paper we discuss several implementation related challenges and will propose adequate solutions. These challenges include robust algorithms to determine time of arrivals of distorted PD waveforms, signal propagation along cable types and configurations as three-core and cross bonded cables, and effect of ring main units or substations on signal propagation. Algorithms based on signal energy and on phase angle in frequency domain are preferred above e.g. threshold detection to determine PD arrival times. By introducing effective dielectric properties, cable parameters for accurate fault location as characteristic impedance and propagation velocity can be estimated also if data on semiconducting layers are unavailable. Models are proposed for cross-bonded connections and for three-core cables with common earth screen. A pulse injection circuit, already included in the PD equipment for time synchronisation, can be employed to extract a model for PDs passing ring main units or even entire substations.

On-line partial discharge (PD-OL) monitoring systems for medium voltage cable connections have recently been introduced in Dutch grids and also a few worldwide. The vast continuous stream of diagnostic data calls for a re-evaluation of statistical methods to be applied for the interpretation of the PD activity. In the present paper a variety of statistical parameters are discussed. These parameters include parameters for observing trends in PD activity over time. The methods are applied to data obtained from several continuous online field measurements collected over a year. The results of analyses on several weak spots which were detected before failure are presented. Results of failed accessories are discussed in relation to their prior PD behavior.

Recently an on-line partial discharge (named PD-OL) for power cables is introduced in mainly Dutch medium voltage grids and first data has become available. This paper discusses the results on statistical analysis, including PD magnitude, PD repetition frequency and PD density distributions, employed to study the degradation of cable connections and their components. The potential of Weibull modelling, as a tool to identify the discharge origin, is investigated. PD fielddata is collected over one year from several connections including suspected weak spots in cables, joints and terminations. Continuous monitoring and trend watching of statistical parameters over time enabled us to detect ongoing aging processes, and several outages were prevented. Two cable circuits are specifically examined in more detail.