Pyroclastic deposits and volcanic history of Mayor Island

The emergent summit of Mayor Island, Bay of Plenty, New Zealand, is a peralkaline rhyolite volcano constructed by: a sequence of lava flows, the Tutaretare Rhyolite Formation new; and pyroclastic deposits, the Oira Pyroclastite Formition (new). These 2 formations constitute the Mayor Island Group new. The pyroclastic deposits mantle most of the outer slopes of the island, in places exceeding 100 m in thickness, and also occur interbedded with lava flows of the main cone. The pyroclastics have been informally assigned on the basis of their compositional, welding and textural, and sedimentary structural characteristics to one or other of 15 lithotypes which may be related to particular modes of eruption and emplacement, of both airfall (phreatic, phreatomagmatic, phreatoplinian, and plinian types) and pyroclastic flow (ignimbrite, nuée ardente, and base surge types origins). A sixteenth lithotype comprises epiclastic deposits formed possibly by catastrophic overspill from an ancestral crater lake. Two new radiocarbon dates on logs from the pyroclastic deposits are recorded: (Wk105) 8000 ± 70 years B.P., and (Wk77) 6340 ± 190 years B.P. Recognition of the calcalkaline Rotoehu and possibly Rotoma Ashes on Mayor Island, together with the new radiocarbon dates, enables definition of 8 phases of major volcanic activity, each separated by relatively quiescent periods with erosion and paleosol formation. Volcanism commenced sometime prior to 42 000 years ago and has continued intermittently up to the eruption of the young dome lavas, possibly less than 1000 years ago. At present, only I Mayor Island-derived tephra has been identified on the mainland of the North Island, namely the Tuhua Tephra dated (Wk77) at source as 6340 ± 190 years B .P. However, the character and magnitude of several of the pyroclastic units on Mayor Island is such that recognition of other peralkaline tephras is anticipated in northern North Island

Understanding the Support Needs of Minority Women with Heart Disease

Background. Cardiovascular disease (CVD) affects minority women disproportionately. WomenHeart: The National Coalition for Women with Heart Disease sought to determine effective ways to support non-Caucasian women with CVD. We surveyed women of color living with CVD to understand their unique CVD-related support needs. Methods. 514 non-white women (100 Hispanic, 180 African American, 104 Asian, 107 Indigenous, 23 multiracial) with CVD from 46 states responded to a 55-question survey (online/telephone, English/Spanish) 8/28/15 through 9/11/15. Results. Among respondents not currently attending support groups, 80% were interested in attending support groups. Of WomenHeart services, respondents were most interested in online message boards. Among new services, respondents were most interested in a support group with a medical expert facilitator. Women with tachycardia wanted a support group with others with the same condition. Those with cardiomyopathy preferred to meet most frequently. Respondents most preferred a monthly support group with flexible membership. Community venues were the most popular location for support groups. Indigenous populations had the lowest CVD knowledge and self-efficacy levels, were most likely to prefer a support group with women of their own race, and wished to meet with their groups most frequently. Multiracial women were most likely to have never been told about clinical trials and were least interested in support groups. Hispanics had the least social support. Conclusions. Minority women with CVD indicated interest in support groups. They may benefit from referrals to tailored support group types, including online platforms facilitated by medical experts, and to cardiac rehabilitation and clinical trials

THERMAL ABLATION ALTERS THE TUMOR MICROENVIRONMENT ACTIVATING A ROBUST IMMUNE RESPONSE.

THERMAL ABLATION ALTERS THE TUMOR MICROENVIRONMENT ACTIVATING A ROBUST IMMUNE RESPONSE. Matthew T Campbell, M.D. Advisor Professor: Padmanee Sharma, M.D Ph.D Ablation techniques including radiofrequency ablation (RFA) and cryoablation have been shown to influence the immune system in animal models. Rare abscopal events, a distant metastatic response to a local procedure, have been observed in humans following both RFA and cryoablation. These rare observations have led to interest in further defining the impact of ablation procedures on the immune signature in the tumor microenvironment and in the systemic circulation. Retrospectively 9 patients with nephrectomy alone (control) were compared to 16 patients treated with ablation. Gene microarray analysis and immunohistochemistry (IHC) for presence of immune cell subtypes were performed on the tissue samples. Prospectively, blood was collected from patients 13 patients who underwent renal ablation for renal cell carcinoma for stage T1a (less than 4cm) at baseline and at day 1, day 28, and 6 months following the procedure. The blood was assessed by flow cytommetry and plasma cytokine levels at each time point following the procedure. GraphPad Prism version 6 was used to perform statistical analysis. The student’s t-test, Kruskal Wallis test, Friedman’s test, and Dunn’s multiple comparisons test were used when appropriate. IHC identified a significant difference (p=0.04) in programmed cell death 1 (PD-1) levels in the tumor invasive margin when comparing control to ablated tumors, while other tumor stains showed no significant differences between the two groups. Gene microarray analysis comparing control patients to three ablation specimens after RFA found significant differential gene expression in pathways and processes involving the immune system. Flow cytommetry markers consistent with previously characterized T regulatory populations of immune cell were found to trend upward at 24 hours following ablation compared to baseline levels. Cytokine analysis revealed elevated levels of IL-6 that increased at day 1 and returned toward baseline by day 28. RFA and cryoablation cause local tissue destruction and an inflammatory immune response that can be detected by gene microarray. Significant changes in tissue IHC, plasma cytokine levels, and immune cell populations in peripheral blood flow cytommetry analysis were not detected

Prevalence of glycosuria and diabetes among Indians and Bantu

No Abstract

Integrin activation - the importance of a positive feedback

Integrins mediate cell adhesion and are essential receptors for the development and functioning of multicellular organisms. Integrin activation is known to require both ligand and talin binding and to correlate with cluster formation but the activation mechanism and precise roles of these processes are not yet resolved. Here mathematical modeling, with known experimental parameters, is used to show that the binding of a stabilizing factor, such as talin, is alone insufficient to enable ligand-dependent integrin activation for all observed conditions; an additional positive feedback is required.Comment: in press in Bulletin of Mathematical Biolog

Brane-world Quantum Gravity

The Arnowitt-Deser-Misner canonical formulation of general relativity is extended to the covariant brane-world theory in arbitrary dimensions. The exclusive probing of the extra dimensions makes a substantial difference, allowing for the construction of a non-constrained canonical theory. The quantum states of the brane-world geometry are defined by the Tomonaga-Schwinger equation, whose integrability conditions are determined by the classical perturbations of submanifolds contained in the Nash's differentiable embedding theorem. In principle, quantum brane-world theory can be tested by current experiments in astrophysics and by near future laboratory experiments at Tev energy. The implications to the black-hole information loss problem, to the accelerating cosmology, and to a quantum mathematical theory of four-sub manifolds are briefly commented.Comment: 14 pages, no figures, JHEP format, to appear in JHEP April 200

Use of MRI in the diagnosis of fetal brain abnormalities in utero (MERIDIAN): a multicentre, prospective cohort study.

BACKGROUND: In-utero MRI (iuMRI) has shown promise as an adjunct to ultrasound but the comparative diagnostic performance has been poorly defined. We aimed to assess whether the diagnostic accuracy and confidence of the prenatal diagnosis of fetal brain abnormalities is improved with iuMRI and assess the clinical impact and patient acceptability of iuMRI. METHODS: We did a multicentre, prospective, cohort study in the UK, at 16 fetal medicine centres, of pregnant women aged 16 years or older whose fetus had a brain abnormality detected by ultrasound at a gestational age of 18 weeks or more, had no contraindications to iuMRI, and consented to enter the study. Women carrying a fetus suspected of having a brain anomaly on ultrasound had iuMRI done within 14 days of ultrasound. The findings were reviewed by two independent panels and used to estimate diagnostic accuracy and confidence by comparison with outcome diagnoses. Changes in diagnosis, prognosis, and clinical management brought about by iuMRI and patient acceptability were assessed. FINDINGS: Participants were recruited between July 29, 2011, and Aug 31, 2014. The cohort was subdivided by gestation into the 18 weeks to less than 24 weeks fetus cohort (n=369) and into the 24 weeks or older fetus cohort (n=201). Diagnostic accuracy was improved by 23% (95% CI 18-27) in the 18 weeks to less than 24 weeks group and 29% (23-36) in the 24 weeks and older group (p<0·0001 for both groups). The overall diagnostic accuracy was 68% for ultrasound and 93% for iuMRI (difference 25%, 95% CI 21-29). Dominant diagnoses were reported with high confidence on ultrasound in 465 (82%) of 570 cases compared with 544 (95%) of 570 cases on iuMRI. IuMRI provided additional diagnostic information in 387 (49%) of 783 cases, changed prognostic information in at least 157 (20%), and led to changes in clinical management in more than one in three cases. IuMRI also had high patient acceptability with at least 95% of women saying they would have an iuMRI study if a future pregnancy were complicated by a fetal brain abnormality. INTERPRETATION: iuMRI improves diagnostic accuracy and confidence for fetal brain anomalies and leads to management changes in a high proportion of cases. This finding, along with the high patient acceptability, leads us to propose that any fetus with a suspected brain abnormality on ultrasound should have iuMRI to better inform counselling and management decisions. FUNDING: National Institute for Health Research Health Technology Assessment programme

Preserving the palaeoenvironmental record in Drylands: Bioturbation and its significance for luminescence-derived chronologies

Luminescence (OSL) dating has revolutionised the understanding of Late Pleistocene dryland activity. However, one of the key assumptions for this sort of palaeoenvironmental work is that sedimentary sequences have been preserved intact, enabling their use as proxy indicators of past changes. This relies on stabilisation or burial soon after deposition and a mechanism to prevent any subsequent re-mobilisation. As well as a dating technique OSL, especially at the single grain level, can be used to gain an insight into post-depositional processes that may distort or invalidate the palaeoenvironmental record of geological sediment sequences. This paper explores the possible impact of bioturbation (the movement of sediment by flora and fauna) on luminescence derived chronologies from Quaternary sedimentary deposits in Texas and Florida (USA) which have both independent radiocarbon chronologies and archaeological evidence. These sites clearly illustrate the ability of bioturbation to rejuvenate ancient weathered sandy bedrock and/or to alter depositional stratigraphies through the processes of exhumation and sub-surface mixing of sediment. The use of multiple OSL replicate measurements is advocated as a strategy for checking for bioturbated sediment. Where significant OSL heterogeneity is found, caution should be taken with the derived OSL ages and further measurements at the single grain level are recommended. Observations from the linear dunes of the Kalahari show them to have no bedding structure and to have OSL heterogeneity similar to that shown from the bioturbated Texan and Florida sites. The Kalahari linear dunes could have therefore undergone hitherto undetected post-depositional sediment disturbance which would have implications for the established OSL chronology for the region

The stellar mass ratio of GK Persei

We study the absorption lines present in the spectra of the long-period cataclysmic variable GK Per during its quiescent state, which are associated with the secondary star. By comparing quiescent data with outburst spectra we infer that the donor star appears identical during the two states and the inner face of the secondary star is not noticeably irradiated by flux from the accreting regions. We obtain new values for the radial velocity semi-amplitude of the secondary star, Kk = 120.5 +- 0.7 km/s, a projected rotational velocity, Vksin i = 61.5 +- 11.8 km/s and consequently a measurement of the stellar mass ratio of GK Per, q = Mk/Mwd = 0.55 +- 0.21. The inferred white dwarf radial velocities are greater than those measured traditionally using the wings of Doppler-broadened emission lines suspected to originate in an accretion disk, highlighting the unsuitability of emission lines for mass determinations in cataclysmic variables. We determine mass limits for both components in the binary, Mk >= 0.48 +- 0.32 Msolar and Mwd >= 0.87 +- 0.24 Msolar.Comment: 8 pages, 8 figures, accepted by MNRA