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Low-temperature antihydrogen atoms are an effective tool to probe the validity of the fundamental laws of Physics, for example the Weak Equivalence Principle (WEP) for antimatter, and -generally speaking- it is obvious that colder atoms will increase the level of precision. After the first production of cold antihydrogen in 2002 [1], experimental efforts have substantially progressed, with really competitive results already reached by adapting to cold antiatoms some well-known techniques pre- viously developed for ordinary atoms. Unfortunately, the number of antihydrogen atoms that can be produced in dedicated experiments is many orders of magnitude smaller than of hydrogen atoms, so the development of novel techniques to enhance the production of antihydrogen with well defined (and possibly controlled) conditions is essential to improve the sensitivity. We present here some experimental results achieved by the AEgIS Collaboration, based at the CERN AD (Antiproton Decelerator) on the production of antihydrogen in a pulsed mode where the production time of 90% of atoms is known with an uncertainty of ~ 250 ns [2]. The pulsed antihydrogen source is generated by the charge-exchange reaction between Rydberg positronium (Ps*) and an antiproton (p¯): p¯ + Ps* → H¯* + e−, where Ps* is produced via the implantation of a pulsed positron beam into a mesoporous silica target, and excited by two consecutive laser pulses, and antiprotons are trapped, cooled and manipulated in Penning-Malmberg traps. The pulsed production (which is a major milestone for AEgIS) makes it possible to select the antihydrogen axial temperature and opens the door for the tuning of the antihydrogen Rydberg states, their de-excitation by pulsed lasers and the manipulation through electric field gradients. In this paper, we present the results achieved by AEgIS in 2018, just before the Long Shutdown 2 (LS2), as well as some of the ongoing improvements to the system, aimed at exploiting the lower energy antiproton beam from ELENA [3].

Thromboelastometry point-of-care coagulation testing facilitates optimised management of bleeding. Previous thromboelastometry systems required the blood sample and liquid reagents to be pipetted in several manual steps by trained personnel. The ROTEMsigma coagulation analyser is a fully automated point-of-care device. We aimed to assess the reference ranges of the new device and to compare the results with those of the predecessor device, the ROTEMdelta. We took blood from healthy volunteers and from hyper- or hypocoagulable patients; blood samples from healthy volunteers served to determine reference ranges for the most important parameters for the ROTEMsigma: CTEXTEM 48-61 s; A5EXTEM 30-51 mm; MCFEXTEM 54-70 mm; CTINTEM 138-174 s; MCFINTEM 51-67 mm and MCFFIBTEM 5-24 mm. We then used blood samples from patients to compare the results obtained between the old and the new device. We found a strong correlation between the same tests performed on two ROTEMsigma devices and between the ROTEMsigma and the ROTEMdelta with respect to the determination of thromboelastometry parameters of hyper- and hypocoagulable patients (all p < 0.001 and R > 0.8). Performance evaluation for the ROTEMsigma device showed very high precision (R > 0.99, p < 0.001). Our reference ranges can serve as an important aid for other hospitals using this new device. [ABSTRACT FROM AUTHOR]

Background: Drinking water of acceptable quality is supposed to be free from faecal coliform and chemical substances that may be hazardous to human health. Water treatment and safe storage at the household level has been advocated as effective means of ensuring safe drinking water. This study was undertaken to determine the microbiological quality of the drinking water at household level in the squatter settlements in the city of Mwanza, Tanzania. Methods: A cross-sectional study was conducted between June 2014 and September 2014. A total of 15 randomly selected water sources (tap) and 207 households' drinking water samples from these sources were studied to ascertain level of water contamination using Membrane Filtration Method. Pre-tested questionnaire was used to collect demographic and other data regarding water treatment and storage. Data were entered, cleaned and analysed using STATA Version 11. Results: All 15 samples from tap used as water sources were found to be free of indicator organism (Escherichia coli) while 109 (52.66%) of drinking water samples from 207 households were found to be contaminated with E. coli. All contaminated drinking water samples were from containers with no cover and spigot. Conclusions: There is a significant level of deterioration of water quality from the source to the drinking cup. Efforts to ensure quality storage methods for drinking water should be addressed at household level. [ABSTRACT FROM AUTHOR]

Provides information on a study which examined the magnetic characteristics of rare earthsystems prepared with high purity rare earths. Methodology of the study; Results and discussion.

Presents information on a study that prepared a rare earth compounds using high purity rare earths. Methodology of the study; Results and discussion on the study.

Here we describe how Staphylococcus aureus bacteria can be rapidly isolated from clinical samples of articular fluid and synovial tissue using magnetic beads coated with the engineered chimeric human opsonin protein, Fc-mannose-binding lectin (FcMBL). The FcMBL-beads were used to capture and magnetically remove bacteria from purified cultures of 12 S. aureus strains, and from 8 articular fluid samples and 4 synovial tissue samples collected from patients with osteoarthritis or periprosthetic infections previously documented by positive S. aureus cultures. While the capture efficiency was high (85%) with purified S. aureus strains grown in vitro, direct FcMBL-bead capture from the clinical samples was initially disappointing (< 5% efficiency). Further analysis revealed that inhibition of FcMBL binding was due to coating of the bacteria by immunoglobulins and immune cells that masked FcMBL binding sites, and to the high viscosity of these complex biological samples. Importantly, capture of pathogens using the FcMBL-beads was increased to 76% efficiency by pretreating clinical specimens with hypotonic washes, hyaluronidase and a protease cocktail. Using this approach, S. aureus bacteria could be isolated from infected osteoarthritic tissues within 2 hours after sample collection. This FcMBL-enabled magnetic method for rapid capture and concentration of pathogens from clinical samples could be integrated upstream of current processes used in clinical microbiology laboratories to identify pathogens and perform antibiotic sensitivity testing when bacterial culture is not possible or before colonies can be detected. [ABSTRACT FROM AUTHOR]

The as-yet unidentified E. coli metabolite colibactin induces DNA damage in eukaryotic cells and promotes tumorigenesis. Its wide distribution in pathogenic and probiotic strains has raised great interest in its structure and biosynthesis. Here we show that colibactin formation involves a rare aminomalonyl unit used as a building block. [ABSTRACT FROM AUTHOR]

Background The Laryngeal Mask Airway ( LMA) ProSealTM and the i- GelTM are two extraglottic devices with either an inflatable cuff or a non-inflatable cuff. Aim We test the hypothesis that oropharyngeal leak pressure and fiberoptic position of the airway tube differ between the size 2 LMA ProSealTM and the i- GelTM in non-paralysed ventilated children. Methods Fifty-one children aged 1.5-6 years weighing 10-25 kg were studied using a crossover design. Anaesthesia was with remifentanil/propofol mixture. The LMA ProSealTM and the i- GelTM were inserted into each patient in random order. Results Oropharyngeal leak pressure for the LMA ProSealTM and the i- GelTM was similar at 22 (5) and 21 (5) cm H2O, respectively. Fiberoptic position of the airway tube for the LMA ProSealTM and the i- GelTM was similar, with the vocal cords visible from the distal airway tube in 94% and 96%, respectively. Conclusion We conclude that oropharyngeal leak pressure and fiberoptic position of the airway tube are similar for the size 2 LMA ProSealTM and i- GelTM in non-paralysed ventilated children. [ABSTRACT FROM AUTHOR]

In this study, the authors examine the relationship between and the efficiency of different approaches to standard (univariate) differential power analysis (DPA) attacks. The authors first show that, when fed with the same assumptions about the target device (i.e. with the same leakage model), the most popular approaches such as using a distance-of-means test, correlation analysis and Bayes attacks are essentially equivalent in this setting. Differences observed in practice are not because of differences in the statistical tests but because of statistical artefacts. Then, the authors establish a link between the correlation coefficient and the conditional entropy in side-channel attacks. In a first-order attack scenario, this relationship allows linking currently used metrics to evaluate standard DPA attacks (such as the number of power traces needed to perform a key recovery) with an information theoretic metric (the mutual information). The authors results show that in the practical scenario defined formally in this study, both measures are equally suitable to compare devices with respect to their susceptibility to DPA attacks. Together with observations regarding key and algorithm independence the authors consequently extend theoretical strategies for the sound evaluation of leaking devices towards the practice of side-channel attacks. [ABSTRACT FROM AUTHOR]

The authors show that a number of existing methods for side-channel defence are essentially the same techniques presented in different contexts. By abstracting this technique, they present necessary conditions which need to be satisfied for it to be successful in preventing side-channel analysis. They also show that concrete application of the technique via randomised field representation produces more efficient implementations than application of the technique via randomised projective coordinates. [ABSTRACT FROM AUTHOR]

Art-based course evaluation could serve as a rich source of information about how a course has affected the educational journey of students and achieved its goals. This study used art to evaluate an all-day seminar for graduate students on research methods, to explore students feelings about research concepts, and to foster understanding of those concepts in a holistic and relevant way. At the seminar's beginning and end, participants made art that expressed their feelings about research, wrote down word associations about research, and rated their desire to do research. At the end, they analyzed their own and the group's artwork. Comparisons of the artwork and other measures suggested that the seminar was able to reduce most participants' anxiety about research without a loss of creativity and energy. Artmaking in the context of research education was thus supported by the study. [ABSTRACT FROM AUTHOR]

SummaryIn a prospective randomized study in children, we compared caudal bupivacaine–clonidine with bupivacaine–morphine to evaluate whether clonidine can be used as an alternative to morphine in caudal anaesthesia. Caudal anaesthesia was administered in 36 children undergoing orchidopexy, hernia repair or circumcision, using 1.5 mL kg-1 bupivacaine 0.18% with either 1 μg kg-1 clonidine (group 1) or 30 μg kg-1 morphine (group 2). Haemodynamic and respiratory parameters, anaesthetic requirements, recovery time and pain score were monitored for 24 h. Eleven children in group 1 and nine children in group 2 did not need any supplementary systemic analgesics throughout the 24-h observation period. Mean (±SD) duration of analgesia in the remaining patients was 6.3 h (±3.3 h) in group 1 and 7.1 h (±3.4 h) in group 2 (P=0.43). Recovery time after anaesthesia was significantly longer in group 1 (16.6±8.8 min) than in group 2 (11.5±4.7 min) (P< 0.05). We conclude that analgesia provided by 1 μg kg-1 clonidine added to caudal bupivacaine is comparable with that provided by 30 μg kg-1 caudal morphine with bupivacaine. Clonidine at this low dose did not cause respiratory depression. [ABSTRACT FROM AUTHOR]