Pressure coefficients of Raman modes of carbon nanotubes resolved by chirality: Environmental effect on graphene sheet

Studies of the mechanical properties of single-walled carbon nanotubes are hindered by the availability only of ensembles of tubes with a range of diameters. Tunable Raman excitation spectroscopy picks out identifiable tubes. Under high pressure, the radial breathing mode shows a strong environmental effect shown here to be largely independent of the nature of the environment . For the G-mode, the pressure coefficient varies with diameter consistent with the thick-wall tube model. However, results show an unexpectedly strong environmental effect on the pressure coefficients. Reappraisal of data for graphene and graphite gives the G-mode Grueuneisen parameter gamma = 1.34 and the shear deformation parameter beta = 1.34.Comment: Submitted to Physical Review

Growth and Feeding Studies on the Algal Feeding Stage of a Pfiesteria-like Dinoflagellate

The dinoflagellate Cryptoperidiniopsis sp. was isolated from sediment samples taken from Virginia estuaries, and established in culture for subsequent growth and feeding studies. The maximum abundance, or yield, of Cryptoperidiniopsis is exponentially related to the concentration of algal prey and is saturated at about 4.00 X 105 mL-1. Salinity from 10-20 ppt and temperature between 15-25 C have no effect on the yield of this form of Cryptoperidiniopsis. Light intensity has a secondary effect in that the algal prey reproduces more quickly in higher light as they are being grazed. Growth rates of Cryptoperidiniopsis were highest with a cryptophyte, Cryptomonas, as food, but growth was also demonstrated utilizing both diatoms and chlorophytes. Cryptoperidiniopsis sp. is similar to Pfiesteria in that it feeds myzocytotically with a peduncle, is similar in size and shape, has a complex life cycle, and is distinguished only by plates hidden under membranes

Growth and Feeding Studies on the Algal Feeding Stage of a Pfiesteria-like Dinoflagellate

The dinoflagellate Cryptoperidiniopsis sp. was isolated from sediment samples taken from Virginia estuaries, and established in culture for subsequent growth and feeding studies. The maximum abundance, or yield, of Cryptoperidiniopsis is exponentially related to the concentration of algal prey and is saturated at about 4.00 X 105 mL-1. Salinity from 10-20 ppt and temperature between 15-25 C have no effect on the yield of this form of Cryptoperidiniopsis. Light intensity has a secondary effect in that the algal prey reproduces more quickly in higher light as they are being grazed. Growth rates of Cryptoperidiniopsis were highest with a cryptophyte, Cryptomonas, as food, but growth was also demonstrated utilizing both diatoms and chlorophytes. Cryptoperidiniopsis sp. is similar to Pfiesteria in that it feeds myzocytotically with a peduncle, is similar in size and shape, has a complex life cycle, and is distinguished only by plates hidden under membranes

Nutrients and Chlorophyll at the Shelf Break Off the Southeastern United States During the Genesis of Atlantic Lows Experiment: Winter 1986

The outer shelf and upper slope off Charleston, South Carolina, were the site of oceanographic and meteorological measurements during the winter of 1986. The purpose of the study was to test ideas about front formation, heat transport, and stratification during cold air outbreaks. An ancillary part of the study was the observation of nutrients and chlorophyll concentrations. The observations extended across the shelf and sometimes crossed the Gulf Stream front. The results show slightly elevated nitrate concentrations in outer shelf waters (1 - 2 μM NO3) with chlorophyll concentrations in the 1 - 1.8 μg L-1 range. When effects of Gulf Stream frontal eddies are eliminated, the estimated wintertime wind-driven transport of nutrients from the deep ocean to the shelf is comparable to that observed during spring and summer. Thus significant onshore nutrient transport can occur throughout the year in this region

Biogeochemical Control of Phosphorus Cycling and Primary Production in Lake Michigan

A 3-yr study in Lake Michigan has shown a 27 mmol P m-2 increase in the mass of total P (TP) in the water during spring when the lake is mixed from surface to sediment. This value is an order of magnitude greater than the annual P input from external sources. TP changed in concert with increases in chlorophyll a and organic N and decreases in nitrate and soluble Si. The concentration of soluble reactive PO4-3 (SRP) remained relatively constant throughout the study. We hypothesize that the SRP concentration is maintained by a chemical equilibrium with calcium-phosphate species. The increased mass of TP arises from the sequestering of P by algae which displaces the chemical equilibrium and allows more P to be released to the water from the sediments. Solar irradiance and the duration of mixing determine the magnitude of the spring bloom and the demand for P that must be supplied through the flux of P from the sediments to the overlying water

Six-month outcomes from Living Well with Diabetes: a randomized trial of a telephone-delivered weight loss and physical activity intervention to improve glycemic control

Intensive lifestyle intervention trials in type 2 diabetes contribute evidence on what can be achieved under optimal conditions, but are less informative for translation in applied settings

Metabolic, health and lifestyle profiling of breast cancer radiotherapy patients and the risk of developing fatigue

Background: Fatigue is commonly reported by cancer patients. In some instances it can persist after treatment is com-pleted. In order to develop effective treatment strategies it is important to understand the mechanisms underlying the development of fatigue and to be able to predict those that may be at greatest risk of experiencing fatigue during and following treatment. The current paper examines predisposing factors for fatigue including altered fatty acid homeosta-sis in a cohort of breast cancer radiotherapy patients. Methodology: Patients had undergone breast-conserving surgery and adjuvant breast irradiation. Prior to radiotherapy the patients were free from significant fatigue. Levels of fatigue were determined prior to and following radiotherapy using the Functional Assessment of Cancer Therapy fatigue sub-scale. Plasma fatty acid levels, urinary and plasma amino acid levels, blood biochemistry factors and general health and lifestyle characteristics were assessed. Results: Following radiotherapy, significant fatigue affected approximately one third of the 26 patients and these subjects were then assigned to the fatigued cohort. Univariate analysis revealed that higher levels of the fatty acids myristic acid and eicosadienoic acid were present for the fatigued cohort prior to radio-therapy. Multivariate analysis also revealed that fatty acid homeostasis was altered between the fatigued and non-fatigued groups at baseline. Orthogonal partial least squares discriminant analysis of the general health, lifestyle and metabolic data revealed that the fatigued and non-fatigued patients could be clustered into two clearly separate groups. Conclusions: The results supported the proposition that the fatigued patients had an underlying metabolic ho-meostasis which may predispose them to the development of fatigue. Biochemical and general health profiling of breast cancer patients has the potential to identify those at most risk of developing significant fatigue following radiotherapy

Cardiovascular disease risk marker responses to breaking up prolonged sedentary time in individuals with paraplegia: the Spinal Cord Injury Move More (SCIMM) randomised crossover laboratory trial protocol

Introduction: Sedentary behaviour is a distinct risk factor for cardiovascular disease (CVD) and could partly explain the increased prevalence of CVD in people with spinal cord injury (SCI). Interrupting prolonged sitting periods with regular short bouts of walking acutely suppresses postprandial glucose and lipids in able-bodied individuals. However, the acute CVD risk marker response to breaking up prolonged sedentary time in people with SCI has not been investigated. Methods and analysis: A randomised two-condition laboratory crossover trial will compare: 1) breaking up prolonged sedentary time with 2 min moderate-intensity arm crank activity every 20 min, with 2) uninterrupted prolonged sedentary time (control) in people with SCI. Outcomes will include acute effects on postprandial glucose, insulin, lipids and blood pressure. Blood samples will be collected and blood pressure measured at regular intervals during each 5.5 h condition. Ethics and dissemination: This study was approved by the Cambridge South NHS Research Ethics Committee. This research will help determine if breaking up prolonged sedentary time could be effective in lowering CVD risk in people with SCI. The findings of the research will be published in a peer review journal and disseminated to relevant user groups. Trial registration: The study is registered as a clinical trial on the ISRCTN register (trial ID: ISRCTN51868437)