Detection of mRNA using the BIACORE

We present the detection of native mRNA using the BIACORE system. The influence of different probes and flow rates on the detection is shown and compared to the hybridisation of oligonucleotides. Probes for mRNA detection were chosen by calculations of secondary structures using energy minimizing criteria based on the algorithm of Zuker. Probe concentrations were optimised as well as the regeneration conditions for the sensor surface. The influence of the flow rate appeared to be more marked for mRNA than for oligonucleotide hybridisation

Inverted hysteresis and negative remanence in a homogeneous antiferromagnet

Magnetic remanence - found in bar magnets or magnetic storage devices - is probably the oldest and most ubiquitous phenomenon underpinning technological applications of magnetism. It is a macroscopic non-equilibrium phenomenon: a remanent magnetisation appears when a magnetic field is applied to an initially unmagnetised ferromagnet, and then taken away. Here, we present an inverted magnetic hysteresis loop in the pyrochlore compound Nd$_2$Hf$_2$O$_7$: the remanent magnetisation points in a direction opposite to the applied field. This phenomenon is exquisitely tunable as a function of the protocol in field and temperature, and it is reproducible as in a quasi-equilibrium setting. We account for this phenomenon in considerable detail in terms of the properties of non-equilibrium population of domain walls which exhibit a magnetic moment between domains of an ordered antiferromagnetic state which itself has zero net magnetisation. Properties and (non-equilibrium) dynamics of topological defects play an important role in modern spintronics, and our study adds an instance where a uniform field couples selectively to domain walls rather than the bulk.Comment: 5 pages, 3 figures in main article and 7 pages, 13 figures in supplementary material

Disentangling Pauli blocking of atomic decay from cooperative radiation and atomic motion in a 2D Fermi gas

The observation of Pauli blocking of atomic spontaneous decay via direct measurements of the atomic population requires the use of long-lived atomic gases where quantum statistics, atom recoil and cooperative radiative processes are all relevant. We develop a theoretical framework capable of simultaneously accounting for all these effects in a regime where prior theoretical approaches based on semi-classical non-interacting or interacting frozen atom approximations fail. We apply it to atoms in a single 2D pancake or arrays of pancakes featuring an effective A level structure (one excited and two degenerate ground states). We identify a parameter window in which a factor of two extension in the atomic lifetime clearly attributable to Pauli blocking should be experimentally observable in deeply degenerate gases with~103 atoms. Our predictions are supported by observation of a number-dependent excited state decay rate on the 1S0 - 3P1 transition in 87Sr atoms.Physic

Inverted hysteresis and negative remanence in a homogeneous antiferromagnet

Magnetic remanence -- found in bar magnets or magnetic storage devices -- is probably the oldest and most ubiquitous phenomenon underpinning technological applications of magnetism. It is a macroscopic non-equilibrium phenomenon: a remanent magnetisation appears when a magnetic field is applied to an initially unmagnetised ferromagnet, and then taken away. Here, we present an inverted magnetic hysteresis loop in the pyrochlore compound Nd2Hf2O7: the remanent magnetisation points in a direction opposite to the applied field. This phenomenon is exquisitely tunable as a function of the protocol in field and temperature, and it is reproducible as in a quasi-equilibrium setting. We account for this phenomenon in considerable detail in terms of the properties of nonequilibrium population of domain walls which exhibit a magnetic moment between domains of an ordered antiferromagnetic state which itself has zero net magnetisation. Properties and (nonequilibrium) dynamics of topological defects play an important role in modern spintronics, and our study adds an instance where a uniform field couples selectively to domain walls rather than the bulk.Physic

Cisplatin-induced ototoxicity: the current state of ototoxicity monitoring in New Zealand.

Background: Many well-known pharmacologic agents have been shown to have toxic effects to the cochleo-vestibular system. Examples of such ototoxic agents include cisplatin and aminoglycoside antibiotics. Ototoxicity monitoring consists of a comprehensive pattern of audiological assessments designed to detect the onset of any hearing loss. Three main methods have emerged over the past decade, and include the basic audiological assessment, extended high frequency (EHF) audiometry, and otoacoustic emission (OAE) measurement. These measures can be used separately or in combination, depending on clinical purpose and patient considerations. It is suggested by the American Academy of Audiology Position Statement and Clinical Practice Guidelines: Ototoxicity Monitoring, that baseline testing be done in a fairly comprehensive manner, including pure-tone thresholds in both the conventional- and extended high frequency ranges, tympanometry, speech audiometry, and the testing of OAEs (AAA, 2009). Anecdotal evidence suggests that New Zealand Audiologists do not currently follow a national ototoxicity monitoring protocol. Therefore the main aim of this study was to explore the current status of ototoxicity monitoring within New Zealand. Hypothesis: It was hypothesized that hospital based Audiology departments across New Zealand each followed their own internal ototoxicity monitoring protocol based, to a large extent, on the guidelines proposed by the American Academy of Audiology and by the American Speech-Language-Hearing Association. Method: Through the use of a Telephone Interview Questionnaire, 16 charge Audiologists were interviewed to establish their current state of knowledge regarding ototoxicity monitoring at 16 out of 20 district health boards in New Zealand. Enquiries about the current systems and procedures in place at their departments together with any suggestions and recommendations to improve on these systems were made. Results: This study found that only 9 of the 16 DHBs interviewed currently follow an ototoxicity monitoring protocol. Furthermore, other than initially hypothesized the origin of the protocols followed by the remaining 7 departments were reported to have ranged from independently developed protocols to historically adopted protocols. One department implemented an adapted version of a protocol by Fausti et al. (Ear and Hearing 1999; 20(6):497-505). This diversity in origin however, does confirm our initial suspicion that no universal and standardized monitoring protocol is currently being followed by Audiologists working in the public health sector of New Zealand