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The first accurate measurements of the α-decay branching ratio and half-life of the Iπ=1/2+ ground state in $^{181}$Tl have been made, along with the first determination of the magnetic moments and I=1/2 spin assignments of the ground states in $^{177,179}$Au. The results are discussed within the complementary systematics of the reduced α-decay widths and nuclear g factors of low-lying, Iπ=1/2+ states in the neutron-deficient lead region. The findings shed light on the unexpected hindrance of the 1/2+→1/2+, $^{181}$Tl→g177Au$^{g}$ α decay, which is explained by a mixing of π3s1/2 and π2d3/2 configurations in $^{177}$Au$^{g}$, whilst $^{181}$Tl$^{g}$ remains a near-pure π3s1/2. This conclusion is inferred from the g factor of $^{177}$Au$^{g}$ which has an intermediate value between those of π3s1/2 and π2d3/2 states. A similar mixed configuration is proposed for the Iπ=1/2+ ground state of $^{179}$Au. This mixing may provide evidence for triaxial shapes in the ground states in these nuclei.

The first accurate measurements of the α-decay branching ratio and half-life of the I π = 1 / 2 + ground state in 181Tl have been made, along with the first determination of the magnetic moments and I = 1 / 2 spin assignments of the ground states in 177,179Au. The results are discussed within the complementary systematics of the reduced α-decay widths and nuclear g factors of low-lying, I π = 1 / 2 + states in the neutron-deficient lead region. The findings shed light on the unexpected hindrance of the 1 / 2 + → 1 / 2 + , 181Tl → g 177 Aug α decay, which is explained by a mixing of π 3 s 1 / 2 and π 2 d 3 / 2 configurations in 177Aug, whilst 181Tlg remains a near-pure π 3 s 1 / 2 . This conclusion is inferred from the g factor of 177Aug which has an intermediate value between those of π 3 s 1 / 2 and π 2 d 3 / 2 states. A similar mixed configuration is proposed for the I π = 1 / 2 + ground state of 179Au. This mixing may provide evidence for triaxial shapes in the ground states in these nuclei.

Neutron deficient N=84 isotones have been synthesised in 106Cd (58Ni) fusion evaporation reactions in an experiment performed at the University of Jyvaskyla accelerator laboratory. Reaction products were identified and their properties measured using the GREAT spectrometer in conjunction with the RITU gas- filled separator and the LISA spectrometer, while the Jurogam II spectrometer was used to measure gamma rays emitted at the target position. Mother-daughter correlations have been used to produce evidence for the first observation of alpha decay from the ground state of 160Os. The Q-value and half-life of the signal were measured to be 7415 (50) keV and 35 +19 -15 us, respectively. No evidence of the expected 8+ isomer was found. Further experimental work at the University of Jyvaskyla has been approved on the strength of this work. Improved measurements of the decay properties of h11/2 state in 159Re and 155Ta have been performed. The half-life of this state in 159Re was measured to be 21(1) us. The decay energy and branching ratios were 6818(6) keV and 5.0(8)% for the alpha decay branch and 1802(5) keV and 95(4) % for the proton decay branch. The proton decay of 155Ta was measured to have an energy of 1429(5) keV and a half-life of 3.3(6) ms. All values are consistent with previous works. Gamma rays above the h11/2 state in 159Re were identified for the first time and comparisons to the odd-Z isotone 157Ta were used to deduce the order of the lowest lying of these gamma rays. Evidence for the expected alpha-decaying 25/2- isomer was found.

Service learning is often heralded as an important way of providing potentially transformative learning opportunities for students to develop empathy and an ethic of care, contributing to student ‘being’ and engagement in the world. However, many scholars have noted that service learning does not inherently and by itself offer students the space to explore their personal responses to the challenges of service work. This can result in service that embeds and perpetuates hierarchy and difference. My research paid more explicit attention to student ‘being’ to explore learnings about self, knowledge and practice. Through data that included interviews, reflective writing and online blogs, I tracked the learning journeys of four students through a service learning course that aims to foreground values and ‘being’. I asked how this focus on ‘being’ affected the students’ learning. I found that through “learning service” (Boyle-Baise et al. 2006) ‘being’ was transformed for each student, which resulted in changed ‘knowing’ and practice., From the link: http://www.journals.ac.za/index.php/sajhe/article/view/501 accessed on 25-04-2016 it is indicated that, "this work is licensed under a Creative Commons Attribution 4.0 International License".

The medium energy ion scattering (MEIS) system at the University of Western Ontario has been modified by replacing the original one-dimensional position sensitive detector with a 2-D array. Calibration and analysis procedures for quantitative depth profiling are devised and established in this work: distortion correction, image tiling, charge state distribution of the scattered hydrogen ions, etc. The software to simultaneously control the sample manipulator (three orthogonal rotations), toroidal electrostatic analyzer and spectrum acquisition has been developed using LabView R . This development makes for easy sample alignment to the incident ion beam and automatically collects the step images. Additionally, the tiling procedure using corrected step images is accomplished within LabView R to produce a final energy–angle spectra. Our QUARK (quantitative analysis of Rutherford kinematics) spectrum simulation package has been modified to provide for non-linear least squares fitting to a measured MEIS energy spectrum. As a reference for quantitative analysis, a shallow Sb-implanted graphite sample was used with normalization to the height of the thick target carbon region by applying 1 H stopping power values from Konac et al. [Nucl. Instr. Meth. Phys. Res. B 136–138 (1998) 159]. To determine the system suitability for compositional analysis, Zr silicate films of thickness 2–7 nm on Si (1 0 0) substrates have been characterized by MEIS, RBS and NRA. The absolute areal densities of constituent elements are in good agreement (within 15%) among the three methods.

This study asks how we can make sense of students' learning in service learning. I employed a qualitative research methodology to explore the learning experiences of four students as they journeyed through the UCT Global Citizenship course: Thinking about volunteering: service, boundaries and power. This is a service learning course which attracts students from all disciplines and years of study. The course has two learning components: the students' self-organised voluntary community service, which forms the primary learning text, and guided facilitation and reflection through face-to-face and online learning activities. I had access to students' coursework which provided two written reflective assignments and a number of online blogs. At a later stage I conducted small-scale in-depth interviews. I used two methods to organise and analyse the data. The first was an analytic framework made up of three interconnected learning domains of 'knowing', 'being' and 'acting' (adapted from Barnett and Coate, 2005); the second was qualitative thematic analysis. My data suggest that we can make sense of students' learning in service learning through an analysis of students' 'being' in relation to their 'knowing' and 'acting'. My data also show that 'being' is embedded in students' 'knowing' and 'doing' and therefore 'being' is a key component of student learning. Additionally, the concept of a 'learning journey' is useful in positioning learning as something that takes place over time and in space. Finally, my data show that context matters: students' "personal foundations of experience" (Boud and Walker, 1991) influence their learning, as does the more immediate context of the classroom and their community service work. This study ends by briefly pointing to two key 'enablers' of students' learning, critical reflection and peer learning.

Several C-9 modified N-acetylneuraminic acid derivatives have been synthesised and evaluated as substrates of N-acetylneuraminic acid aldolase. Simple C-9 acyl or ether modified derivatives of N-acetylneuraminic acid were found to be accepted as substrates by the enzyme, albeit being transformed more slowly than Neu5Ac itself. 1H NMR spectroscopy was used to evaluate the extent of the enzyme catalysed transformation of these compounds. Interestingly, the chain-extended Neu5Ac derivative 16 is not a substrate for N-acetylneuraminate lyase and behaves as an inhibitor of the enzyme.

Efficient enantioselective syntheses of the important cardiac drug (+)-cis-(2S,3S)-diltiazem from (E)-methyl 4-methoxyphenylpropenoate via either the (2R,3S)- or (2S,3R)-enantiomers of threo-methyl 3-(4-methoxyphenyl)-2,3-dihydroxypropanoate are described.

The mean concentration of thyroxine (T4) in the plasma of the rhesus monkey Macaca mulatta (53 ± 8 (s.d.) nmol/l) is less than the lower limit of the range of concentrations normally found in man; conversely, the mean concentration of tri-iodothyronine (T3) in monkey plasma (2·45 ± 0·52 (s.d.) nmol/l) is at the upper end of the normal human range. The basal concentrations of TSH in the plasma, as measured by radioimmunoassay, were comparable in the two species (mean concentration of TSH in monkey plasma 1·53 mu./l; range 0·2–2·6 mu./l). The administration of radioactive iodine (13–15 mCi Na131I) to these monkeys regularly induced hypothyroidism. The concentration of TSH in the plasma began to rise 3 weeks after the administration of radioactive iodine and reached a maximum and sustained level (30–300 mu./l) after 3 months, at which time the concentrations of T4 and T3 in the plasma were immeasurable. Other pituitary and adrenal functions were unaffected by the hypothyroid state. Protracted sedation of normal monkeys with phencyclidine hydrochloride resulted firstly within hours in a decline in the concentration of T3 in the plasma without any corresponding alteration in the concentration of T4 and secondly, after 24 h, in a marked rise in the concentrations of both T4 and TSH. The connection between these changes is not clear but phencyclidine does not seem to be a suitable sedative for prolonged studies of the pituitary– thyroid system in normal monkeys. In contrast, sedation with phencyclidine did not affect the concentration of TSH in the plasma of hypothyroid monkeys provided that their body temperature was maintained near normal; the level of TSH fell if the monkey became cold when sedated and rose if it became overheated. The rise in the level of TSH in the plasma of normal monkeys after administration of synthetic thyrotrophin releasing hormone (TRH) was less than that observed in man, although the effect of the increase upon the plasma T3 concentration was similar in the two species. The response of monkeys to incremental doses of TRH showed that a maximum response was obtained at a lower equivalent dose (1·0 μg/kg body weight) than in man, but administration of this dose (or a greater one) to hypothyroid monkeys caused only small increases in the concentration of TSH in the plasma. The rapid intravenous injection of 0·2 or 2·0 μg T3 had no effect on the level of TSH in the plasma of hypothyroid monkeys, but 20 μg caused a progressive decline which reached a nadir 35% below the baseline at 5 h; the level of TSH returned to its basal value after 24 h. The raised concentration of TSH in the plasma of hypothyroid monkeys could be reduced to the normal range by the repeated administration of 20 μg T3 over 3 or 4 days.

The Anglo-American cataloguing rules, 2nd ed., are discussed in relation to the Paris Principles, trends in international standardization in cataloguing and aspects of machine processing of bibliographical data. The international role of AACR 2 as a catalogue code is also considered.

Bilateral injections of tri-iodothyronine (T3, 2 ng in 2 μl artificial cerebrospinal fluid, CSF) were made into the hypothalami of 15 hypothyroid rhesus monkeys (Macaca mulatta) prepared with chronically implanted intrahypothalamic cannulae. In 29 out of 96 such injections, the concentration of thyrotrophin (TSH) in the plasma fell rapidly by more than 30% and returned to the basal value over the succeeding 48 h, in 13 experiments the fall was 20–30% and in the remaining 54 experiments the level of TSH was unaltered. With [125I]T3, the extent of diffusion of T3 through the hypothalamus in these experiments was shown to be very limited. The hypothalamic injection sites were subsequently identified histologically and it was found that in those experiments in which the level of TSH in the plasma had fallen, T3 had been injected into either the dorsomedial nucleus or the lateral hypothalamic area extending into the preoptic region. Injection of artificial CSF alone into these areas of the hypothalamus did not affect the concentration of TSH. Direct intrapituitary injections of T3 (4 ng) resulted in small and inconstant changes in the concentration of TSH in the plasma and injections of T3 (400 ng) into the third ventricle were without any effect. These experiments demonstrate that T3 can rapidly inhibit the secretion of TSH by a direct action upon defined parts of the hypothalamus.

Physics letters / B B 786, 355 - 363 (2018). doi:10.1016/j.physletb.2018.10.005, Published by North-Holland Publ., Amsterdam

The β decay of Hg207 into the single-proton-hole nucleus Tl207 has been studied through γ-ray spectroscopy at the ISOLDE Decay Station (IDS) with the aim of identifying states resulting from coupling of the πs1/2-1, πd3/2-1, and πh11/2-1 shell model orbitals to the collective octupole vibration. Twenty-two states were observed lying between 2.6 and 4.0 MeV, eleven of which were observed for the first time, and 78 new transitions were placed. Two octupole states (s1/2-coupled) are identified and three more states (d3/2-coupled) are tentatively assigned using spin-parity inferences, while further h11/2-coupled states may also have been observed for the first time. Comparisons are made with state-of-the-art large-scale shell model calculations and previous observations made in this region, and systematic underestimation of the energy of the octupole vibrational states is noted. We suggest that in order to resolve the difference in predicted energies for collective and noncollective t=1 states (t is the number of nucleons breaking the Pb208 core), the effect of t=2 mixing may be reduced for octupole-coupled states. The inclusion of mixing with t=0,2,3 excitations is necessary to replicate all t=1 state energies accurately.