Exploring thoracic kyphosis and incident fracture from vertebral morphology with high-intensity exercise in middle-aged and older men with osteopenia and osteoporosis: a secondary analysis of the LIFTMOR-M trial.

Our aim was to explore change in kyphosis and vertebral fracture incidence following 8 months of high-intensity resistance and impact training (HiRIT) or machine-based isometric axial compression (IAC) training in men with osteopenia and osteoporosis. HiRIT and IAC improved posture. HiRIT participants did not experience progression or incident vertebral fracture. IAC participants did experience progression and incident vertebral fracture. INTRODUCTION: The Lifting Intervention For Training Muscle and Osteoporosis Rehabilitation for Men (LIFTMOR-M) trial examined efficacy and safety of an eight-month, supervised, high-intensity progressive resistance and impact training (HiRIT) program compared with machine-based isometric axial compression (IAC) training in middle-aged and older men with low areal bone mineral density (aBMD). The primary purpose of the current work was to explore change in thoracic kyphosis and incident fracture from vertebral morphology following eight-months of HiRIT or IAC training. The secondary purpose was to explore change in clinical kyphosis measures for HiRIT, IAC and a non-randomized, matched control group. METHODS: Men (≥ 45 yrs), with low aBMD, were recruited and randomized to HiRIT or IAC, or designated control. Clinical measures of thoracic kyphosis with inclinometry were determined. Cobb angle of kyphosis and vertebral fracture assessment using the Genant semi-quantitative method were determined from lateral thoracolumbar DXA (Medix DR, Medilink, France). Per-protocol (n = 40) and intention-to-treat (n = 93) analyses were conducted. RESULTS: Forty participants (HiRIT n = 20, IAC n = 20; 66.1 ± 7.8 yrs.; lumbar spine T-score - 0.1 ± 0.8; femoral neck T-score - 1.5 ± 0.5) underwent clinical kyphosis measures and thoracolumbar DXA at baseline and follow-up. No between-group differences were detected in kyphosis change, however, within-group improvements in neutral (HiRIT - 2.3 ± 0.8°; IAC - 2.5 ± 0.8°) and 'standing tall' (HiRIT - 2.4 ± 0.8°; IAC - 2.0 ± 0.8°) postures were observed (p < 0.05). HiRIT improved Cobb angle (- 3.5 ± 1.5°, p = 0.027) from baseline. Over the 8 months, no incident vertebral fractures nor progression of prevalent vertebral fractures occurred for HiRIT participants. Five incident fractures of thoracic vertebrae occurred for IAC and one wedge fracture progressed. Ninety-three participants underwent clinical kyphosis measures at both time-points (HiRIT n = 34, IAC n = 33, control n = 26). HiRIT exhibited a reduction in 'standing tall' kyphosis compared to control (- 2.3 ± 0.6° versus 1.4 ± 0.7°, p < 0.05), but no other between-group differences were detected. CONCLUSIONS: Although there was no difference in change between intervention groups, thoracic kyphosis appeared to improve in both HiRIT and IAC with exercise exposure. HiRIT improved 'standing tall' posture in comparison to usual activities. HiRIT was not associated with vertebral fracture progression or incident vertebral fracture, but for some IAC participants there was evidence of progression of vertebral fracture severity and incident vertebral fractures, in our small sample. Larger trials are required to confirm the observations of the current work, which was exploratory in nature.

High-intensity exercise did not cause vertebral fractures and improves thoracic kyphosis in postmenopausal women with low to very low bone mass: the LIFTMOR trial.

Our aim was to assess risk of vertebral fracture during high-intensity resistance and impact training (HiRIT) for postmenopausal women with low bone mass. HiRIT did not induce vertebral fracture, as evidenced by a reduction in kyphosis following 8 months of training and a lack of change in vertebral morphology. INTRODUCTION: The LIFTMOR trial demonstrated a novel, HiRIT program notably improved bone mass in postmenopausal women with osteopenia and osteoporosis. While no clinical signs or symptoms of vertebral crush fracture were evident during the trial, anecdotal feedback suggests that concerns about safety of HiRIT in the osteoporosis demographic remain. The aim of the current work was to assess vertebral body morphology, Cobb angle, and clinical measures of thoracic kyphosis in participants in the LIFTMOR trial for evidence of vertebral fracture following 8 months of supervised HiRIT. METHODS: Participants were randomized to either 8 months of 30-min, twice-weekly, supervised HiRIT or unsupervised, low-intensity, home-based exercise (CON). Lateral thoracolumbar DXA scans (Medix DR, Medilink, France) were performed at baseline and follow-up. Cobb angle was determined, and vertebral fracture identification was performed using the semiquantitative Genant method. Clinical kyphosis measurements were performed in relaxed standing (neutral posture) and standing tall using an inclinometer and a flexicurve. RESULTS: The HiRIT group exhibited a reduction in inclinometer-determined standing tall thoracic kyphosis compared to CON (- 6.7 ± 8.2° vs - 1.6 ± 8.1°, p = 0.031). Both the HiRIT and CON groups exhibited within-group improvement in kyphosis in relaxed standing as measured by both inclinometer and flexicurve (p < 0.05). There were no changes in vertebral fracture classification in the HiRIT group post-intervention. A single, new, wedge deformity was observed for CON. CONCLUSIONS: Supervised HiRIT was not associated with an increased risk of vertebral fracture in postmenopausal women with low bone mass. Indeed, a clinically relevant improvement in thoracic kyphosis was observed following 8 months of supervised HiRIT, further supporting its efficacy as an osteoporosis intervention for postmenopausal women with low to very low bone mass.

The Forteo Patient Registry linkage to multiple state cancer registries: study design and results from the first 8 years.

The Forteo Patient Registry (FPR) aims to estimate the incidence of osteosarcoma in US patients treated with teriparatide. Enrollment began in 2009 and will continue through 2019, with linkage planned through 2024. To date, no incident cases of osteosarcoma have been identified among patients registered in the FPR. INTRODUCTION: The Forteo Patient Registry (FPR) was established in 2009 to estimate the incidence of osteosarcoma in US patients treated with teriparatide. The objective of this paper is to describe study methods, challenges encountered, and progress to date. METHODS: The FPR is a prospective US registry designed to link data from participants annually with state cancer registries. Patient enrollment is planned for 10 years (2009-2019) and annual linkage with US state cancer registries for 15 years (2010-2024). All US state cancer registries and DC were invited to participate. Patients are recruited using pre-enrollment materials included in teriparatide device packaging, kits, and brochures distributed by health-care providers; a toll-free number; and a study website. A linkage algorithm is used to match data from enrolled participants with cancer registry data. RESULTS: For the eighth annual linkage in 2017, information necessary for linkage with 63,270 patients in the FPR was submitted to each of the 42 participating registries. These patients contributed approximately 242,782 person-years of follow-up. A total of 5268 adult osteosarcoma cases diagnosed since January 1, 2009, were available for linkage from participating state cancer registries. To date, no incident cases of osteosarcoma have been identified among patients registered in the FPR. CONCLUSIONS: Based on the estimated 242,782 person-years of observation as of the eighth annual linkage and projecting current enrollment rate to study end in 2024, it is anticipated that the completed study will be able to detect a fourfold increase in the risk of osteosarcoma if one exists.

Background levels of micro-organisms in the busy urban environment of transport hubs.

AIMS: We constantly interact with our surrounding microbiome, including the micro-organisms present in highly populated public places. However, data on everyday exposure to background levels of micro-organisms are limited. To address this, bacteria and fungi were collected and enumerated in settled dust from railway stations. METHODS AND RESULTS: Samples were collected weekly for 52 weeks, from up to three pre-determined surfaces in each of 17 railway stations in England and Scotland. Trained staff at each station took surface wipes, sending them to the laboratory for culture-based analysis for total bacteria and fungi. Maximum yields of bacteria at the stations were 107 -108 colony forming units (CFU) per cm2 , and 104 -105 CFU per cm2 for fungi. CONCLUSIONS: There was evidence of seasonal trends, with bacterial numbers rising from spring through to winter, while fungal numbers peaked in autumn. Microbial numbers were similar in samples taken at the same time at a given station. Influences on contamination levels were likely to be a combination of passenger numbers and station layout, with dust generated from construction work also contributing. SIGNIFICANCE AND IMPACT OF THE STUDY: A baseline of typical human exposure to micro-organisms in public transport hubs was established through the generation of a comprehensive database.

Search for Cosmic-Ray Electron and Positron Anisotropies with Seven Years of Fermi Large Area Telescope Data.

The Large Area Telescope on board the Fermi Gamma-ray Space Telescope has collected the largest ever sample of high-energy cosmic-ray electron and positron events since the beginning of its operation. Potential anisotropies in the arrival directions of cosmic-ray electrons or positrons could be a signature of the presence of nearby sources. We use almost seven years of data with energies above 42 GeV processed with the Pass 8 reconstruction. The present data sample can probe dipole anisotropies down to a level of 10^{-3}. We take into account systematic effects that could mimic true anisotropies at this level. We present a detailed study of the event selection optimization of the cosmic-ray electrons and positrons to be used for anisotropy searches. Since no significant anisotropies have been detected on any angular scale, we present upper limits on the dipole anisotropy. The present constraints are among the strongest to date probing the presence of nearby young and middle-aged sources.

The relationship between clinical and standardized tests for hand-arm vibration syndrome.

BACKGROUND: Standardized laboratory tests are undertaken to assist the diagnosis and staging of hand-arm vibration syndrome (HAVS), but the strength of the relationship between the tests and clinical stages of HAVS is unknown. AIMS: To assess the relationship between the results of thermal aesthesiometry (TA), vibrotactile (VT) thresholds and cold provocation (CP) tests with the modified Stockholm scales for HAVS and to determine whether the relationship is affected by finger skin temperature. METHODS: Consecutive records of workers referred to a Tier 5 HAVS assessment centre from 2006 to 2015 were identified. The diagnosis and staging of cases was undertaken from the clinical information contained in the records. Cases with alternative or mixed diagnoses were excluded and staging performed according to the modified Stockholm scale without knowledge of the results of the standardized laboratory tests. RESULTS: A total of 279 cases of HAVS were analysed. Although there was a significant trend for sensorineural (SN) and vascular scores to increase with clinical stage (P < 0.01), there was no significant difference in scores between 2SN early and 2SN late or between 2SN late and 3SN. There was moderate correlation between the TA and VT scores and the clinical SN stages (r = 0.6). This correlation did not change when subjects were divided into those with a finger skin temperature <30 and >30°C. CP scores distributed bimodally and correlated poorly with clinical staging (r = 0.2). CONCLUSIONS: Standardized SN tests distinguish between the lower Stockholm stages, but not above 2SN early. This has implications for health surveillance and UK policy.

Zinc transporter 8 autoantibodies: what is their clinical relevance in gestational diabetes?

AIMS: To investigate the prevalence, clinical significance and antepartum to postpartum trajectory of zinc transporter 8 autoantibodies, a novel marker of islet autoimmunity, in women with gestational diabetes mellitus. METHODS: A total of 302 consecutive women attending a multi-ethnic Australian gestational diabetes clinic were prospectively studied. Zinc transporter 8 autoantibodies were measured at gestational diabetes diagnosis and 3 months postpartum using an enzyme-linked immunosorbent assay, and were correlated with maternal phenotype, antepartum and postpartum glucose tolerance, treatment and perinatal outcomes. RESULTS: Of the 302 women, 30 (9.9%) were positive for one islet autoantibody antepartum. No participant had multiple islet autoantibodies. Zinc transporter 8 autoantibodies were the most prevalent autoantibody [zinc transporter 8 autoantibodies: 13/271 women (4.8%); glutamic acid decarboxylase 7/302 women (2.3%); insulinoma-associated antigen-2: 6/302 women (2.0%); insulin: 4/302 women (1.3%)]. Zinc transporter 8 autoantibody positivity was associated with a higher fasting glucose level on the antepartum oral glucose tolerance test, but not with BMI, insulin use, perinatal outcomes or postpartum glucose intolerance. Five of the six women who tested positive for zinc transporter 8 autoantibodies antepartum were negative for zinc transporter 8 autoantibodies postpartum, which corresponded to a significant decline in titre antepartum to postpartum (26.5 to 3.8 U/ml; P=0.03). This was in contrast to the antepartum to postpartum trajectory of the other islet autoantibodies, which remained unchanged. CONCLUSIONS: Zinc transporter 8 autoantibodies were the most common islet autoantibody in gestational diabetes. Zinc transporter 8 autoantibody positivity was associated with slightly higher fasting glucose levels and, unlike other islet autoantibodies, titres declined postpartum. Zinc transporter 8 autoantibodies may be a marker for islet autoimmunity in a proportion of women with gestational diabetes, but the clinical relevance of zinc transporter 8 autoantibodies in pregnancy and gestational diabetes requires further investigation.

The future of hospital at home: a qualitative interview study of healthcare staff.

PURPOSE: Hospital at Home (HaH) services are expanding to provide acute multidisciplinary care in an individual's home. In this pilot study, we interviewed HaH staff to understand challenges and opportunities for service development. METHODS: We conducted 23 semi-structured interviews with multidisciplinary staff working across three HaH services in Scotland. The questions focussed on service strengths and challenges. RESULTS: Four themes emerged: raising referral awareness, service design and efficiency, staff security on home visits, and sustainability. HaH staff described Emergency Department posters, experience days for non-HaH staff, and daily communication of virtual bed capacity to raise awareness for referrals. Ideas for maximising clinician time were prioritised to improve service efficiency and investment in electric vehicles was strongly supported to mitigate climate impact. CONCLUSION: We found high job satisfaction and engagement amongst HaH staff. Our interviews suggest enthusiasm for further development of HaH while raising important challenges to address during service expansion.

A tandem duplication in the D-loop of human mitochondrial DNA is associated with deletions in mitochondrial myopathies.

About 40 per cent of patients with mitochondrial myopathies have two populations of mitochondrial DNA (mtDNA) in muscle, one of which is deleted. All patients with single mtDNA deletions and neurological disease are sporadic cases, suggesting that deletions arise as fresh mutational events. We have detected a low abundance heteroplasmic tandem duplication involving the displacement loop of mtDNA in 18 of 58 patients with deletions and 5/5 of their mothers, but not in normal subjects. The location of the duplication to a region that controls both replication and transcription of mtDNA could explain features suggesting mild mitochondrial dysfunction in the muscle biopsies of three patients' mothers, and a predisposition to deletion.

Meiotic stability and genotype-phenotype correlation of the trinucleotide repeat in X-linked spinal and bulbar muscular atrophy.

Expansion of the trinucleotide repeat (CAG)n in the first exon of the androgen receptor gene is associated with a rare motor neuron disorder, X-linked spinal and bulbar muscular atrophy. We have found that expanded (CAG)n alleles undergo alteration in length when transmitted from parent to offspring. Of 45 meioses examined, 12 (27%) demonstrated a change in CAG repeat number. Both expansions and contractions were observed, although their magnitude was small. There was a greater rate of instability in male meiosis than in female meiosis. We also found evidence for a correlation between disease severity and CAG repeat length, but other factors seem to contribute to the phenotypic variability in this disorder.

Seismic reflection images of the Moho underlying melt sills at the East Pacific Rise.

The determination of melt distribution in the crust and the nature of the crust-mantle boundary (the 'Moho') is fundamental to the understanding of crustal accretion processes at oceanic spreading centres. Upper-crustal magma chambers have been imaged beneath fast- and intermediate-spreading centres but it has been difficult to image structures beneath these magma sills. Using three-dimensional seismic reflection images, here we report the presence of Moho reflections beneath a crustal magma chamber at the 9 degrees 03' N overlapping spreading centre, East Pacific Rise. Our observations highlight the formation of the Moho at zero-aged crust. Over a distance of less than 7 km along the ridge crest, a rapid increase in two-way travel time of seismic waves between the magma chamber and Moho reflections is observed, which we suggest is due to a melt anomaly in the lower crust. The amplitude versus offset variation of reflections from the magma chamber shows a coincident region of higher melt fraction overlying this anomalous region, supporting the conclusion of additional melt at depth.

GTP-dependent segregation of H-ras from lipid rafts is required for biological activity.

Different sites of plasma membrane attachment may underlie functional differences between isoforms of Ras. Here we show that palmitoylation and farnesylation targets H-ras to lipid rafts and caveolae, but that the interaction of H-ras with these membrane subdomains is dynamic. GTP-loading redistributes H-ras from rafts into bulk plasma membrane by a mechanism that requires the adjacent hypervariable region of H-ras. Release of H-ras-GTP from rafts is necessary for efficient activation of Raf. By contrast, K-ras is located outside rafts irrespective of bound nucleotide. Our studies identify a novel protein determinant that is required for H-ras function, and show that the GTP/GDP state of H-ras determines its lateral segregation on the plasma membrane.

Dominant-negative caveolin inhibits H-Ras function by disrupting cholesterol-rich plasma membrane domains.

The plasma membrane pits known as caveolae have been implicated both in cholesterol homeostasis and in signal transduction. CavDGV and CavKSY, two dominant-negative amino-terminal truncation mutants of caveolin, the major structural protein of caveolae, significantly inhibited caveola-mediated SV40 infection, and were assayed for effects on Ras function. We find that CavDGV completely blocked Raf activation mediated by H-Ras, but not that mediated by K-Ras. Strikingly, the inhibitory effect of CavDGV on H-Ras signalling was completely reversed by replenishing cell membranes with cholesterol and was mimicked by cyclodextrin treatment, which depletes membrane cholesterol. These results provide a crucial link between the cholesterol-trafficking role of caveolin and its postulated role in signal transduction through cholesterol-rich surface domains. They also provide direct evidence that H-Ras and K-Ras, which are targeted to the plasma membrane by different carboxy-terminal anchors, operate in functionally distinct microdomains of the plasma membrane.

pKa prediction from an ab initio bond length: part 2--phenols.

The prediction of pK(a) continues to attract much attention with ongoing investigations into new ways to predict pK(a) accurately, where predicted pK(a) values deviate less than 0.50 log units from experiment. We show that a single descriptor, i.e. an ab initio bond length, can predict pK(a). The emphasis was placed on model simplicity and a demonstration that more accurate predictions emerge from single-bond-length models. A data set of 171 phenols was studied. The carbon-oxygen bond length, connecting the OH to the phenyl ring, consistently provided accurate predictions. The pK(a) of meta- and para-substituted phenols is predicted here by a single-bond-length model within 0.50 log units. However, accurate prediction of the pK(a) of ortho-substituted phenols necessitated their splitting into groups called high-correlation subsets in which the pK(a) of the compounds strongly correlated with a single bond-length. The highly compound-specific single-bond-length models produced better predictions than models constructed with more compounds and more bond lengths. Outliers were easily identified using single-bond-length models and in most cases we were able to determine the reason for the outlier discrepancy. Furthermore, the single-bond-length models showed better cross-validation statistics than the PLS models constructed using more than one bond length. For all of the single-bond-length models, RMSEE was less than 0.50. For the majority of the models, RMSEP was less than 0.50. The results support the use of multiple high-correlation subsets and a single bond-length to predict pK(a). Six one-term linear equations are listed as a starting point for the construction of a more comprehensive list covering a larger variety of compound classes.

pKa prediction from an ab initio bond length: part 3--benzoic acids and anilines.

The prediction of pK(a) from a single ab initio bond length has been extended to provide equations for benzoic acids and anilines. The HF/6-31G(d) level of theory is used for all geometry optimisations. Similarly to phenols (Part 2 of this series of publications), the meta-/para-substituted benzoic acids can be predicted from a single model constructed from one bond length. This model had an impressive RMSEP of 0.13 pK(a) units. The prediction of ortho-substituted benzoic acids required the identification of high-correlation subsets, where the compounds in the same subset have at least one of the same (e.g. halogens, hydroxy) ortho substituent. Two pK(a) equations are provided for o-halogen benzoic acids and o-hydroxybenzoic acids, where the RMSEP values are 0.19 and 0.15 pK(a) units, respectively. Interestingly, the bond length that provided the best model differed between these two high-correlation subsets. This demonstrates the importance of investigating the most predictive bond length, which is not necessarily the bond involving the acid hydrogen. Three high-correlation subsets were identified for the ortho-substituted anilines. These were o-halogen, o-nitro and o-alkyl-substituted aniline high-correlation subsets, where the RMSEP ranged from 0.23 to 0.44 pK(a) units. The RMSEP for the meta-/para-substituted aniline model was 0.54 pK(a) units. This value exceeded our threshold of 0.50 pK(a) units and was higher than both the m-/p-benzoic acids in this work and the m-/p-phenols (RMSEP = 0.43) of Part 2. Constructing two separate models for the meta- and para- substituted anilines, where RMSEP values of 0.63 and 0.33 pK(a) units were obtained respectively, revealed it was the meta-substituted anilines that caused the large RMSEP value. For unknown reasons the RMSEP value increased with the addition of a further twenty meta-substituted anilines to this model. The C-N bond always produced the best correlations with pK(a) for all the high-correlation subsets. A higher level of theory and an ammonia probe improved the statistics only marginally for the hydroxybenzoic acid high-correlation subsets.

Mortality and cancer incidence among British agricultural pesticide users.

BACKGROUND: Although the acute effects of pesticides in humans are well known, uncertainty still exists about the health effects of chronic low-level exposure to pesticides. AIMS: To compare mortality and cancer incidence experienced by a cohort of British pesticide users to that of the Great Britain (GB) population. METHODS: The Pesticide Users Health Study (PUHS) comprises users of agricultural pesticides who have Certificates of Competence under the Control of Pesticides Regulations 1986. Participants were followed up between 1987 and 2004 (cancer incidence) or 2005 (mortality). Standardized mortality ratios (SMRs) and Standardized incidence ratios (SIRs) were estimated for outcomes of interest identified from the literature. RESULTS: Altogether, 62,960 pesticide users were followed up for 829,709 person-years (to 31 December 2005). Most participants were male (94%) and based in England (86%). All-cause mortality was lower for both men [SMR 0.58, 95% confidence interval (CI) 0.55-0.60] and women (SMR 0.71, 95% CI 0.52-0.98) compared to the GB population. Mortality and incidence were below those expected for all cancers combined among men (SMR 0.71, 95% CI 0.66-0.77; SIR 0.85, 95% CI 0.81-0.90), particularly for cancers of the lip, oral cavity and pharynx, digestive organs and respiratory system. The incidence of testicular cancer, non-melanoma skin cancer and multiple myeloma were above expected. Mortality from injury by machinery was significantly above expected for men (SMR 4.21, 95% CI 2.11-8.42). CONCLUSIONS: This study suggests that pesticide users in the PUHS are generally healthier than the national population but may have excesses of non-melanoma skin cancer, testicular cancer and multiple myeloma.

Physics in strong magnetic fields near neutron stars.

Electromagnetic phenomena occurring in the strong magnetic fields of neutron stars are currently of great interest in high-energy astrophysics. Observations of rotation rate changes and cyclotron lines in pulsars and gamma-ray bursts indicate that surface magnetic fields of neutron stars often exceed 10(12) gauss. In fields this strong, where electrons behave much as if they were in bound atomic states, familiar processes undergo profound changes, and exotic processes become important. Strong magnetic fields affect the physics in several fundamental ways: Energies perpendicular to the field are quantized, transverse momentum is not conserved, and electron-positron spin is important. Neutron stars therefore provide a unique laboratory for the study of physics in extremely high fields that cannot be generated on Earth.

Crustal Thickness on the Mid-Atlantic Ridge: Bull's-Eye Gravity Anomalies and Focused Accretion.

Spreading segments of the Mid-Atlantic Ridge show negative bull's-eye anomalies in the mantle Bouguer gravity field. Seismic refraction results from 33 degrees S indicate that these anomalies can be accounted for by variations in crustal thickness along a segment. The crust is thicker in the center and thinner at the end of the spreading segment, and these changes are attributable to variations in the thickness of layer 3. The results show that accretion is focused at a slow-spreading ridge, that axial valley depth reflects the thickness of the underlying crust, and that along-axis density variations should be considered in the interpretation of gravity data.

Seismic structure of the southern East pacific rise.

Seismic data from the ultrafast-spreading (150 to 162 millimeters per year) southern East Pacific Rise show that the rise axis is underlain by a thin (less than 200 meters thick) extrusive volcanic layer (seismic layer 2A) that thickens rapidly off axis. Also beneath the rise axis is a narrow (less than 1 kilometer wide) melt sill that is in some places less than 1000 meters below the sea floor. The small dimensions of this molten body indicate that magma chamber size does not depend strongly on spreading rate as predicted by many ridge-crest thermal models. However, the shallow depth of this body is consistent with an inverse correlation between magma chamber depth and spreading rate. These observations indicate that the paradigm of ridge crest magma chambers as small, sill-like, midcrustal bodies is applicable to a wide range of intermediate- and fast-spreading ridges.

Seismic Images of Active Magma Systems Beneath the East Pacific Rise Between 17{degrees}05' and 17{degrees}35'S.

Seismic reflection data from the East Pacific Rise between 17 degrees 05' and 17 degrees 35'S image a magma lens that varies regularly in depth and width as ridge morphology changes, confirming the notion that axial morphology can be used to infer ridge magmatic state. However, at 17 degrees 26'S, where the ridge is locally shallow and broad, the magma lens is markedly shallower and wider than predicted from regional trends. In this area, submersible dives reveal recent volcanic eruptions. These observations indicate that it is where the width and depth of the magma chamber differ from regional trends, indicating an enhanced magmatic budget, that is diagnostic of current magmatism.