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Rib bone biopsy samples are often used to estimate changes in skeletal mineral reserves in cattle but differences in sampling procedures and the bone measurements reported often make interpretation and comparisons among experiments difficult. ‘Full-core’ rib bone biopsy samples, which included the external cortical bone, internal cortical bone and trabecular bone (CBext, CBint and Trab, respectively), were obtained from cattle known to be in phosphorus (P) adequate (Padeq) or severely P-deficient (Pdefic) status. Experiments 1 and 2 examined growing steers and Experiment 3 mature breeder cows. The thickness of cortical bone, specific gravity (SG), and the amount and concentration of ash and P per unit fresh bone volume, differed among CBext, CBint and Trab bone. P concentration (mg/cc) was closely correlated with both SG and ash concentrations (pooled data, r=0.99). Thickness of external cortical bone (CBText) was correlated with full-core P concentration (FC-Pconc) (pooled data, r=0.87). However, an index, the amount of P in CBext per unit surface area of CBext (PSACB; mg P/mm2), was more closely correlated with the FC-Pconc (pooled data, FC-Pconc=37.0+146×PSACB; n=42, r=0.94, RSD=7.7). Results for measured or estimated FC-Pconc in 10 published studies with cattle in various physiological states and expected to be Padeq or in various degrees of Pdefic status were collated and the ranges of FC-Pconc indicative of P adequacy and P deficiency for various classes of cattle were evaluated. FC-Pconc was generally in the range 130 to 170 and 100 to 120 mg/cc fresh bone in Padeq mature cows and young growing cattle, respectively. In conclusion, the FC-Pconc could be estimated accurately from biopsy samples of CBext. This allows comparisons between studies where full-core or only CBext biopsy samples of rib bone have been obtained to estimate changes in the skeletal P status of cattle and facilitates evaluation of the P status of cattle.
We present an overview of the survey for radio emission from active stars that has been in progress for the last six years using the observatories at Fleurs, Molonglo, Parkes and Tidbinbilla. The role of complementary optical observations at the Anglo-Australian Observatory, Mount Burnett, Mount Stromlo and Siding Spring Observatories and Mount Tamborine are also outlined. We describe the different types of star that have been included in our survey and discuss some of the problems in making the radio observations.
Photoelectric B and V light curves and high dispersion spectroscopic observations were obtained in 1985 February for the rapidly rotating spotted star HD 36705. The visual light range was about 0.09 magnitude, with a well correlated B-V change of approximately 0.04 magnitude, the star being redder when faintest. There is evidence for a broadband flare of ~0.05 magnitude in V and 0.07 magnitude in B. This occurred near maximum light.
Spectroscopic observations show a variation in the equivalent width of the Ca K emission by a factor of about two in antiphase with the photometric variations, maximum emission corresponding to minimum brightness. This is probably due to bright plages and enhanced chromospheric heating associated with the photospheric starspots.
High dispersion, high signal-to-noise spectroscopic observations confirm the presence of lithium λ 6708 as reported by Rucinski (1982, 1985).
Several interpretations of the nature of HD 36705 are discussed; however at present none is completely satisfactory and further observations are required. As the star is probably at less than 100 pc, a parallax determination may be possible, and could help answer many of the questions concerning HD 36705.
The subsurface exploration of other planetary bodies can be used to unravel their geological history and assess their habitability. On Mars in particular, present-day habitable conditions may be restricted to the subsurface. Using a deep subsurface mine, we carried out a program of extraterrestrial analog research – MINe Analog Research (MINAR). MINAR aims to carry out the scientific study of the deep subsurface and test instrumentation designed for planetary surface exploration by investigating deep subsurface geology, whilst establishing the potential this technology has to be transferred into the mining industry. An integrated multi-instrument suite was used to investigate samples of representative evaporite minerals from a subsurface Permian evaporite sequence, in particular to assess mineral and elemental variations which provide small-scale regions of enhanced habitability. The instruments used were the Panoramic Camera emulator, Close-Up Imager, Raman spectrometer, Small Planetary Linear Impulse Tool, Ultrasonic drill and handheld X-ray diffraction (XRD). We present science results from the analog research and show that these instruments can be used to investigate in situ the geological context and mineralogical variations of a deep subsurface environment, and thus habitability, from millimetre to metre scales. We also show that these instruments are complementary. For example, the identification of primary evaporite minerals such as NaCl and KCl, which are difficult to detect by portable Raman spectrometers, can be accomplished with XRD. By contrast, Raman is highly effective at locating and detecting mineral inclusions in primary evaporite minerals. MINAR demonstrates the effective use of a deep subsurface environment for planetary instrument development, understanding the habitability of extreme deep subsurface environments on Earth and other planetary bodies, and advancing the use of space technology in economic mining.
Radio interferometric observations of extragalactic radio sources have been made with antennas at the Haystack Observatory in Massachusetts and the Owens Valley Radio Observatory in California during fourteen separate experiments distributed between September 1976 and May 1978. The components of the baseline vector and the coordinates of the sources were estimated from the data from each experiment separately. The root-weighted-mean-square scatter about the weighted mean (“repeatability”) of the estimates of the length of the 3900 km baseline was approximately 7 cm, and of the source coordinates, approximately or less, except for the declinations of low-declination sources. With the source coordinates all held fixed at the best available, a posteriori, values, and the analyses repeated for each experiment, the repeatability obtained for the estimate of baseline length was 4 cm. From analyses of the data from several experiments simultaneously, estimates were obtained of changes in the x component of pole position and in the Earth's rotation (UT1). Comparison with the corresponding results obtained by the Bureau International de l'Heure (BIH) discloses systematic differences. In particular, the trends in the radio interferometric determinations of the changes in pole position agree more closely with those from the International Polar Motion Service (IPMS) and from the Doppler observations of satellites than with those from the BIH.
We report static and time-resolved terahertz (THz) conductivity measurements of a highperformance thermoelectric material containing tellurium nanowires in a PEDOT:PSS matrix. Composites were made with and without sulfur passivation of the nanowires surfaces. The material with sulfur linkers (TeNW/PD-S) is less conductive but has a longer carrier lifetime than the formulation without (TeNW/PD). We find real conductivities at f = 1THz of σTeNW/PD = 160 S/cm and σTeNW/PD-S = 5.1 S/cm. These values are much larger than the corresponding DC conductivities, suggesting DC conductivity is limited by structural defects. The free-carrier lifetime in the nanowires is controlled by recombination and trapping at the nanowire surfaces. We find surface recombination velocities in bare tellurium nanowires (22m/s) and TeNW/PD-S (40m/s) that are comparable to evaporated tellurium thin films. The surface recombination velocity in TeNW/PD (509m/s) is much larger, indicating a higher interface trap density.
Titan, Mars, and Venus are three largely unmagnetized planetary bodies with dense atmospheres that are immersed in external and highly dynamic magnetized plasma flows. Mars and Venus interact with the solar wind, whereas Titan usually interacts with the rotating magnetosphere of Saturn, and only occasionally is subject to shocked solar wind during brief excursions into Saturn's magnetosheath (Figure 12.1). Titan's atmosphere is ionized by the energetic plasma flow, together with solar and cosmic ray radiation (see Chapter 11), and the resulting ionosphere provide a conductive environment with which the external plasma flow interacts. The ability of the ionosphere to carry an electrical current plays an important role in the dynamics and energetics of the ionosphere, and through collisions, to the deposition of energy and momentum into the neutral atmosphere. This magnetosphere/ionosphere interaction at Titan involves the formation of an induced magnetosphere around Titan with interaction boundaries that drapes the magnetic field lines into a long tail behind the moon, already detected by the instruments of the Voyager 1 spacecraft (e.g., Ness et al., 1982; Gurnett et al., 1982) during its swift fly-by of Titan's plasma wake. The interaction causes ionospheric convection and facilitates the escape of ionospheric plasma through the tail to the surrounding streaming magnetosphere past Titan. In addition, Titan's vast neutral gas environment becomes partly ionized; the created ions are picked up by the induced convection electric field by the streaming magnetospheric plasma and drift away in a gyrating motion, at the same time mass loading the streaming plasma so it slows down in the neighborhood of the moon.
Let p be any prime number, and let G be a compact p-adic Lie group with a closed normal subgroup H such that G/H is isomorphic to the additive subgroup of p-adic integers ℤp. Write ∧(G) (respectively, ∧(H)) for the Iwasawa algebra of G (respectively, H) with coefficients in ℤp. As was shown in , there exists an Ore set in ∧(G) which enables one to define a characteristic element, with all the desirable properties, for a special class of torsion ∧(G)-modules, namely those finitely generated left ∧(G)-modules W such that W/W(p) is finitely generated over ∧(H); here W(p) denotes the p-primary submodule of W. This simple piece of pure algebra leads to a class of deep arithmetic problems, which will be the main concern of this paper. We shall loosely call these problems the MH(G)-conjectures, and it should be stressed that their validity is essential even for the formulation of the main conjectures of non-commutative Iwasawa theory.
Let F be a finite extension of ℚ, and F∞ a Galois extension of F satisying (i) G = Gal(F∞/F) is a p-adic Lie group, (ii) F∞/F is unramified outside a finite set of primes of F, and (iii) F∞ contains the cyclotomic ℤp-extension of F, which we denote by Fcyc.
Depressive symptoms may increase the risk of progressing from mild cognitive impairment (MCI) to dementia. Consumption of n-3 PUFA may alleviate both cognitive decline and depression. The aim of the present study was to investigate the benefits of supplementing a diet with n-3 PUFA, DHA and EPA, for depressive symptoms, quality of life (QOL) and cognition in elderly people with MCI. We conducted a 6-month double-blind, randomised controlled trial. A total of fifty people aged >65 years with MCI were allocated to receive a supplement rich in EPA (1·67 g EPA+0·16 g DHA/d; n 17), DHA (1·55 g DHA+0·40 g EPA/d; n 18) or the n-6 PUFA linoleic acid (LA; 2·2 g/d; n 15). Treatment allocation was by minimisation based on age, sex and depressive symptoms (Geriatric Depression Scale, GDS). Physiological and cognitive assessments, questionnaires and fatty acid composition of erythrocytes were obtained at baseline and 6 months (completers: n 40; EPA n 13, DHA n 16, LA n 11). Compared with the LA group, GDS scores improved in the EPA (P = 0·04) and DHA (P = 0·01) groups and verbal fluency (Initial Letter Fluency) in the DHA group (P = 0·04). Improved GDS scores were correlated with increased DHA plus EPA (r 0·39, P = 0·02). Improved self-reported physical health was associated with increased DHA. There were no treatment effects on other cognitive or QOL parameters. Increased intakes of DHA and EPA benefited mental health in older people with MCI. Increasing n-3 PUFA intakes may reduce depressive symptoms and the risk of progressing to dementia. This needs to be investigated in larger, depressed samples with MCI.
Heart rate (HR) variability and large arterial compliance can be improved using fish oils. DHA, a component of fish oil, has cardiovascular health benefits, but its effect on HR variability (HRV) and arterial compliance is yet to be quantified. Sixty-seven overweight or obese adults (thirty-six males and thirty-one females; 53 (sem 2) year; BMI 31·7 (sem 1·1) kg/m2) were randomly allocated to consume either 6 g/d sunola oil (control; n 17), fish oil (260 mg DHA+60 mg EPA per g) at doses of 2 g/d (n 16), 4 g/d (n 17) or 6 g/d (n 17). Blood pressure, HR and compliance of large and small arteries were measured while supine at baseline and after 12 weeks in all participants, and HRV was assessed in a subgroup of forty-six participants. There was no effect of fish oil on blood pressure, small artery compliance or HR. However, the low frequency:high frequency ratio of HRV decreased with increasing doses of fish oil (r − 0·34, P = 0·02), while large artery compliance increased (r 0·34, P = 0·006). Moreover, the changes in these biomarkers were significantly correlated (r − 0·31, P = 0·04) and may reflect fish oil-induced improvements in arterial function and cardiac autonomic regulation.
To estimate the sensitivity and specificity of computed tomography used for the detection of extranodal spread of metastatic head and neck squamous cell carcinoma, by experienced head and neck radiologists.
Materials and methods:
Participants had undergone a neck dissection for head and neck squamous cell carcinoma, together with computed tomography scanning prior to surgery (accessible for reporting). Computed tomography images were independently examined by two experienced head and neck radiologists. Nodal involvement by squamous cell carcinoma and the presence or absence of extranodal spread were recorded. Results were compared to the histological specimen. The sensitivity, specificity and positive predictive value of using computed tomography for the detection of nodal involvement and presence or absence of extranodal spread were estimated, and 95 per cent confidence intervals were calculated.
Results and analysis:
The study analysed 149 neck dissections. When using computed tomography to detect the extranodal spread of head and neck squamous cell carcinoma, radiologists A and B had sensitivities of 66 and 80 per cent, specificities of 91 and 90 per cent, and positive predictive values of 85 and 87 per cent, respectively.
The sensitivity and specificity of radiological detection of extranodal spread from head and neck squamous cell carcinoma is not well reported in the literature. Accuracy of reporting improves in the hands of experienced head and neck radiologists. This finding has clinical implications for surgical planning and adjuvant therapy requirements.
The risks posed by a range of acoustic scientific instruments were assessed by the construction of matrices of scale and likelihood. We recognized six levels of impact ranging from none or short term, minimal behavioural response (Level 1) to multiple injuries and fatalities and/or compromised populations (Level 6) and six levels of likelihood ranging from “Expected in almost all instances” (Level 1) to “cannot see how it could happen” (Level 6). Typical scientific instruments ranging from acoustic releases to large air gun arrays were assessed. To provide a perspective for the risks of scientific operations, other activities were also ranked. These included large chemical explosions, submarine detection sonars implicated in some mass strandings of cetaceans and normal Antarctic shipping activities. The conclusion reached was that most scientific instruments pose a similar or lower risk than normal shipping operations. High source-level equipment poses some risk to individual animals' hearing and so should be mitigated. Likewise, survey planning should be designed to avoid trapping animals in narrow, constricted sea ways. Long term, cumulative impacts are still difficult to detect in areas with greater anthropogenic noise than the Antarctic but we concluded that any possible long term impacts should be mitigated by maintaining the low levels of activity using high source-level equipment through data sharing and survey planning.
Let $G$ be a
$p$-adic Lie group,
and let $\varLambda(G)$ be
its Iwasawa algebra. The present paper establishes results about the structure theory of finitely generated
up to pseudo-isomorphism, which are largely parallel to the classical theory when
$G$ is abelian
(except for basic differences which occur for those torsion modules which do not possess a non-zero global
annihilator). We illustrate our general theory by concrete examples of such modules arising from the Iwasawa
theory of elliptic curves without complex multiplication over the field generated by all of their
$p$-power torsion points.
This study sought to evaluate the benefit of utilizing a nutritionist review of a self-administered food frequency questionnaire (FFQ), to determine whether accuracy could be improved beyond that produced by the self-administered questionnaire alone.
Participants randomized into a dietary intervention trial completed both a FFQ and a 4-day food record (FR) at baseline before entry into the intervention. The FFQ was self-administered, photocopied and then reviewed by a nutritionist who used additional probes to help complete the questionnaire. Both the versions – before nutritionist review and after nutritionist review – were individually compared on specific nutrients to the FR by means, correlations and per cent agreement into quintiles.
Settings and subjects:
Three hundred and twenty-four people, a subset of participants from the Polyp Prevention Trial – a randomized controlled trial examining the effect of a low-fat, high-fibre, high fruit and vegetable dietary pattern on the recurrence of adenomatous polyps – were recruited from clinical centres at the University of Utah, University of Buffalo, Memorial Sloan Kettering Cancer Center in New York and Kaiser Permanente Medical Program in Oakland.
Reviewing the FFQ increased correlations with the FR for every nutrient, and per cent agreement into quintiles for all nutrients except calcium. Energy was underestimated in both versions of the FFQ but to a lesser degree in the version with review.
One must further evaluate whether the increases seen with nutritionist review of the FFQ will enhance our ability to predict diet–disease relationships and whether it is cost-effective when participant burden and money spent utilizing trained personnel are considered.
The performance of a 15-cm-radius applied-magnetic-field ion diode was investigated on the PBFA II accelerator at a power of 23 TW. The power coupling between the accelerator and diode was measured and compared with numerical simulations that show the effects of the electron flow in the MITL. The power coupled to the cathode of the diode was 18 MW. Measurements of the lithium beam generated from an electric-field-emission LiF anode showed a lithium beam power of 9 TW. The lithium beam was ballistically focused in a gas cell filled with 2 torr argon. The resultant focused power density was ∼1.8 TW/cm2 equivalent on a cylindrical target at the centerline of the diode. The focused power was limited by the 20- to 30-mR divergence of the beam caused by the LiF source used and by virtual cathode instabilities in the anode–cathode gap. The ion mode instability in the virtual cathode was studied extensively by measurement of waves in the ion emission pattern from the anode and of the E-P0 correlation between variations in the beam energy and transverse momentum. The instability Played a dominant role in the limitation of the focused lithium power.
The results of six experiments on growing cattle weighing 140–480 kg, and with liveweight gains of —0·46 to 1·11 kg/day, were reanalysed to provide estimates of their phosphorus (P) requirements. The 158 data sets were from individually penned cattle offered barley straw-based diets ad libitum with dry matter digestibilities of 0·53–O·65, or from cattle grazing tropical pastures with in vitro dry matter digestibilities ranging from 0·50 to 0·62. Various concentrations of dietary energy, nitrogen (N), calcium (Ca) and P were imposed during the course of the experiments with the penned cattle and various rates of application of P fertilizer changed the botanic and nutrient composition of the forages available to the grazing cattle. The P balances and P kinetics of the cattle were studied using 32P as a tracer.
Over the range of P intakes normally observed in cattle consuming forage diets (10–60 mg/kg LW), the coefficient of P absorption was high and not affected by age or liveweight. The regression coefficient relating P intake to P absorption was 0·77 for unsupplemented grazing cattle and 0·82 for penned supplemented cattle. When the plasma inorganic P concentrations were < 50 mg/1, urinary P excretion of the penned cattle was low, as were the endogenous faecal P losses of both the penned and grazing cattle. These losses were concluded to represent obligatory losses and were related to dry matter intake (r = 0·73) in the range 9–17 mg P/kg LW.
The total P requirements of growing cattle were estimated as g/day and g/kg DM intake from this data. The requirements of cattle consuming forage diets were 40–50% lower than those published by the Agricultural and Food Research Council (AFRC 1991), even though the same equation for the net requirements for growth was utilized.
Fully electromagnetic, relativistic, two-dimensional, particle-in-cell (PIC) simulations of barrel-type and extractor-type Applied-B ion diodes have increased our confidence in the design of present and future diodes for the Particle Beam Fusion Accelerator II (PBFA II). In addition, the data from various experiments on Pro to I, Proto II, and PBFA I Applied-B ion diodes are inconsistent with previous models of diode operation, based on anode-cathode gap closure from expanding plasmas. A new model has been devised and applied to the PBFA II diode to explain the diode impedance and its time history, and to suggest methods for controlling the impedance.
1. The influence of trace-nutrient-binding proteins on the growth of coliforms, streptococci and lactobacilli in the gastrointestinal tract was examined in neonatal rabbits delivered germ-free and dosed with an artificial flora (ESL), or born conventionally and dosed with ESL or rabbit faeces.
2. In the stomach and small intestine of both gnotobiotic and conventional animals the counts of coliforms were usually atypically high and those of streptococci were always low. In the colon the counts of coliforms and streptococci were high. Lactobacilli usually became established in the gut of the gnotobiotic animals but were not found in the conventional rabbits.
3. Sterilization (freeze-drying followed by γ-irradiation) of the milk decreased its capacity to bind added iron by 45% and vitamin B12 by 30%. When compared with raw milk, feeding of radiation-sterilized milk did not affect the viable count of coliforms and streptococci in the gut of gnotobiotic animals.
4. Saturating the nutrient-binding proteins in milk with Fe, folic acid and vitamin B12 had no effect on the numbers of coliforms, streptococci and lactobacilli recovered from the intestine.