Commensurate 4a04a_0 period Charge Density Modulations throughout the Bi2Sr2CaCu2O8+xBi_2Sr_2CaCu_2O_{8+x} Pseudogap Regime

Theories based upon strong real space (r-space) electron electron interactions have long predicted that unidirectional charge density modulations (CDM) with four unit cell (4$a_0$) periodicity should occur in the hole doped cuprate Mott insulator (MI). Experimentally, however, increasing the hole density p is reported to cause the conventionally defined wavevector $Q_A$ of the CDM to evolve continuously as if driven primarily by momentum space (k-space) effects. Here we introduce phase resolved electronic structure visualization for determination of the cuprate CDM wavevector. Remarkably, this new technique reveals a virtually doping independent locking of the local CDM wavevector at $|Q_0|=2\pi/4a_0$ throughout the underdoped phase diagram of the canonical cuprate $Bi_2Sr_2CaCu_2O_8$. These observations have significant fundamental consequences because they are orthogonal to a k-space (Fermi surface) based picture of the cuprate CDM but are consistent with strong coupling r-space based theories. Our findings imply that it is the latter that provide the intrinsic organizational principle for the cuprate CDM state

Machine Learning in Electronic Quantum Matter Imaging Experiments

Essentials of the scientific discovery process have remained largely unchanged for centuries: systematic human observation of natural phenomena is used to form hypotheses that, when validated through experimentation, are generalized into established scientific theory. Today, however, we face major challenges because automated instrumentation and large-scale data acquisition are generating data sets of such volume and complexity as to defy human analysis. Radically different scientific approaches are needed, with machine learning (ML) showing great promise, not least for materials science research. Hence, given recent advances in ML analysis of synthetic data representing electronic quantum matter (EQM), the next challenge is for ML to engage equivalently with experimental data. For example, atomic-scale visualization of EQM yields arrays of complex electronic structure images, that frequently elude effective analyses. Here we report development and training of an array of artificial neural networks (ANN) designed to recognize different types of hypothesized order hidden in EQM image-arrays. These ANNs are used to analyze an experimentally-derived EQM image archive from carrier-doped cuprate Mott insulators. Throughout these noisy and complex data, the ANNs discover the existence of a lattice-commensurate, four-unit-cell periodic, translational-symmetry-breaking EQM state. Further, the ANNs find these phenomena to be unidirectional, revealing a coincident nematic EQM state. Strong-coupling theories of electronic liquid crystals are congruent with all these observations.Comment: 44 pages, 15 figure

Reductive Coupling of Diynes at Rhodium Gives Fluorescent Rhodacyclopentadienes or Phosphorescent Rhodium 2, 2’-Biphenyl Complexes

Reactions of [Rh(κ2-O,O-acac)(PMe3)2] (acac=acetylacetonato) and α,ω-bis(arylbutadiynyl)alkanes afford two isomeric types of MC4 metallacycles with very different photophysical properties. As a result of a [2+2] reductive coupling at Rh, 2,5-bis(arylethynyl)rhodacyclopentadienes (A) are formed, which display intense fluorescence (Φ=0.07–0.54, τ=0.2–2.5 ns) despite the presence of the heavy metal atom. Rhodium biphenyl complexes (B), which show exceptionally long-lived (hundreds of μs) phosphorescence (Φ=0.01–0.33) at room temperature in solution, have been isolated as a second isomer originating from an unusual [4+2] cycloaddition reaction and a subsequent β-H-shift. We attribute the different photophysical properties of isomers A and B to a higher excited state density and a less stabilized T1 state in the biphenyl complexes B, allowing for more efficient intersystem crossing S1→Tn and T1→S0. Control of the isomer distribution is achieved by modification of the bis- (diyne) linker length, providing a fundamentally new route to access photoactive metal biphenyl compounds

Mutations of the BRAF gene in human cancer

Cancers arise owing to the accumulation of mutations in critical genes that alter normal programmes of cell proliferation, differentiation and death. As the first stage of a systematic genome-wide screen for these genes, we have prioritized for analysis signalling pathways in which at least one gene is mutated in human cancer. The RAS RAF MEK ERK MAP kinase pathway mediates cellular responses to growth signals. RAS is mutated to an oncogenic form in about 15% of human cancer. The three RAF genes code for cytoplasmic serine/threonine kinases that are regulated by binding RAS. Here we report BRAF somatic missense mutations in 66% of malignant melanomas and at lower frequency in a wide range of human cancers. All mutations are within the kinase domain, with a single substitution (V599E) accounting for 80%. Mutated BRAF proteins have elevated kinase activity and are transforming in NIH3T3 cells. Furthermore, RAS function is not required for the growth of cancer cell lines with the V599E mutation. As BRAF is a serine/threonine kinase that is commonly activated by somatic point mutation in human cancer, it may provide new therapeutic opportunities in malignant melanoma

Sialendoscopic treatment of recurrent juvenile parotitis: A South African case series

Background. Recurrent juvenile parotitis (RJP) is a well-recognised cause of  parotitis in childhood. Sialendoscopy has been extensively used for the investigation and treatment of many benign salivary disorders, and now offers a minimally invasive approach to RJP.Objectives. To investigate the epidemiology and disease profile of RJP, and review the efficacy of sialendoscopy for its investigation and treatment.Methods. The relevant literature on RJP was reviewed, and a retrospective folder review was performed for all patients who had undergone sialendoscopy for RJP at two South African (SA) hospitals between April 2013 and September 2015. Patients’ epidemiological and clinical data were recorded, as well as the findings and outcomes of ultrasonography and sialendoscopy. In particular, the time following treatment without any further recurrences was recorded as a measure of success.Results. Five children underwent sialendoscopic investigation and treatment for RJP. Their demographic and disease profiles and the results of investigations and  treatments were in keeping with published literature. No surgical complications  occurred, and no patients reported any further symptoms postoperatively, with an average follow-up of 22 months.Conclusion. Although small in sample size, this is the first reported case series in the SA literature on the use of sialendoscopy for RJP, and the results are consistent with internationally published data. Sialendoscopy is regarded as safe and effective for the diagnosis and management of RJP, and should be considered for patients who remain symptomatic after conservative management

Dairying and Employment in the Amuri: 1983 to 2002

The dairy industry is currently experiencing a staff shortage, as are many other industries. It has experienced rapid expansion, and the situation is made worse by the poor image of the industry. This expansion has often occurred in areas with little prior dairying. The Amuri region, North Canterbury, is one such area. The conversion of farms to dairying began in I983, following the commissioning of the 17000-hectare Waiau Plains Irrigation Scheme in 1980. There are now 49 herds in the area. Some of the initial dairy farming experiences were very bad, giving all dairying in the region a poor reputation. The Amuri region is 'geographically isolated basin', and situated approximately 90 minutes from Christchurch, with limited social opportunities for the farm staff This resulted in extreme difficulties attracting and retaining good staff in the area. In response to this situation, the dairy farmers in the area formed the Amuri Dairy Employers Group, in March 2000. This group established a constitution including: Mandatory member employer training; Agreeing to an independent annual audit of member employment practices; and Agreeing to a Code of Practice for employment standards. I have undertaken a two-year investigation of the effects of the Amuri Dairy Employers Group, on dairy farming employment and the wider social effects in the Amuri area. A case-study approach has been used to gather the information. This research was conducted as part of a Masters of Commerce (Agriculture)

Immunoglobulin G; structure and functional implications of different subclass modifications in initiation and resolution of allergy.

IgE and not IgG is usually associated with allergy. IgE lodged on mast cells in skin or gut and basophils in the blood allows for the prolonged duration of allergy through the persistent expression of high affinity IgE receptors. However, many allergic reactions are not dependent on IgE and are generated in the absence of allergen specific and even total IgE. Instead, IgG plasma cells are involved in induction of, and for much of the pathogenesis of, allergic diseases. The pattern of IgG producing plasma cells in atopic children and the tendency for direct or further class switching to IgE are the principle factors responsible for long-lasting sensitization of mast cells in allergic children. Indirect class switching from IgG producing plasma cells has been shown to be the predominant pathway for production of IgE while a Th2 microenvironment, genetic predisposition, and the concentration and nature of allergens together act on IgG plasma cells in the atopic tendency to undergo further immunoglobulin gene recombination. The seminal involvement of IgG in allergy is further indicated by the principal role of IgG4 in the natural resolution of allergy and as the favourable immunological response to immunotherapy. This paper will look at allergy through the role of different antibodies than IgE and give current knowledge of the nature and role of IgG antibodies in the start, maintenance and resolution of allergy

Mutations in FRMD7, a newly identified member of the FERM family, cause X-linked idiopathic congenital nystagmus.

Idiopathic congenital nystagmus is characterized by involuntary, periodic, predominantly horizontal oscillations of both eyes. We identified 22 mutations in FRMD7 in 26 families with X-linked idiopathic congenital nystagmus. Screening of 42 singleton cases of idiopathic congenital nystagmus (28 male, 14 females) yielded three mutations (7%). We found restricted expression of FRMD7 in human embryonic brain and developing neural retina, suggesting a specific role in the control of eye movement and gaze stability

Future Dairy Farm Employment - An Application of the Human Capability Framework

Dairy InSight research project, no. 10015/2003 sought to establish the future employment needs of the industry from a study of the future dairy farm labour market; to estimate future labour required and available; and to provide a full discussion of factors affecting those estimates. The report on which this paper is based was intended to provide a foundation document for any future studies of work and employment in dairy farming. The research strategy adopted was to use the Human Capability Framework (HCF) to analyse the future dairy farm labour market. The use of the HCF to analyse the future dairy farm employment situation was implemented by a systematic consideration of each of the elements influencing the supply side (Capacity) of the dairy farm labour market, the demand side (Opportunity), and the bringing of those both together (Matching), comprising the three main components of the HCF. Statistical resources were reviewed and found distinctly wanting. Other documentary sources were considered, expert opinions canvassed, and key sites and parties visited, to facilitate the industry wide analysis. All components of the analysis, together with practical recommendations, were put together in a single report, which ·was submitted to Dairy InSight, the industry good funder for the dairy industry. They are summarised in this paper

Results from the first use of low radioactivity argon in a dark matter search

Liquid argon is a bright scintillator with potent particle identification properties, making it an attractive target for direct-detection dark matter searches. The DarkSide-50 dark matter search here reports the first WIMP search results obtained using a target of low-radioactivity argon. DarkSide-50 is a dark matter detector, using two-phase liquid argon time projection chamber, located at the Laboratori Nazionali del Gran Sasso. The underground argon is shown to contain Ar-39 at a level reduced by a factor (1.4 +- 0.2) x 10^3 relative to atmospheric argon. We report a background-free null result from (2616 +- 43) kg d of data, accumulated over 70.9 live-days. When combined with our previous search using an atmospheric argon, the 90 % C.L. upper limit on the WIMP-nucleon spin-independent cross section based on zero events found in the WIMP search regions, is 2.0 x 10^-44 cm^2 (8.6 x 10^-44 cm^2, 8.0 x 10^-43 cm^2) for a WIMP mass of 100 GeV/c^2 (1 TeV/c^2 , 10 TeV/c^2).Comment: Accepted by Phys. Rev.