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Archimedean spirals are common in various fields such as biology, engineering, astronomy, and space physics. Here we report the discovery of patterns resembling the general Archimedean spirals in particle distributions in the Earth radiation belt. Our analytic theory and numerical simulations demonstrate that electrons with initially asymmetric spatial distributions form such spirals in the inner magnetosphere, where particles at smaller radial distances move more slowly in angular velocity. These spirals result in time‐varying peaks and valleys in particle fluxes, referred to as "zebra stripes," which are well consistent with Van Allen Probes measurements. Although the initial asymmetric distribution may be seeded by the electric field in the magnetosphere, the spiral formation does not require them. Furthermore, we show that, due to the same fundamental motion of charged particles in regions dominated by dipole fields, this spiral phenomenon may also appear in the proton distributions, as well as in planetary magnetospheres. Plain Language Summary: The Archimedean spiral is named after the 3rd‐century BC Greek mathematician Archimedes. Such spirals have been seen from the sunflower head, Iridogorgia to galactic arms. Throughout the solar system, the average configuration of the background magnetic field also aligns with Archimedean spirals, as it is dragged by charged particles that are ejected radially from the surface of the rotating Sun, a fundamental discovery made by E. N. Parker. However, it remains unknown whether an Archimedean spiral exists in the near‐Earth space. Here we report for the first time the discovery of patterns similar to the general Archimedean spirals in particle distributions in the radiation belt, a region filled with energetic charged particles surrounding Earth. This happens because electrons closer to the Earth move slower in the angular direction. These spirals manifest as time‐varying peaks and valleys in the electron spectagrams, named as "zebra stripes." Our theory and simulation results are well consistent with the measurements of the Van Allen Probes. Besides, our theory predicts that these spirals could occur on protons and other planets with similar magnetic fields. Key Points: The first known discussion and discovery of Archimedean spiral structures in Earth's magnetosphereElectrons' general Archimedean spiral‐like distribution results in the formation of "zebra stripes" in the inner radiation beltOur findings hold exciting implications for understanding magnetospheric physics beyond our planet [ABSTRACT FROM AUTHOR]

The purpose of this paper is to present standard results on the effect of nonlinearities on the computed pulsatile flow in a cylindrical distensible tube as a first stage in the calculation of flow in a tapered tube and blood flow in arteries. The calculations are made using the pressure-radius relationship of a rubber tube with no longitudinal motion and for a linearised relationship. The one-dimensional equations of motion are solved by the method of finite differences. The values of skin friction that are incorporated are determined from the vorticity and continuity equations for a rigid tube and a correction made to the current diameter at each time step. The accuracy of the results is assessed and the effect of varying parameters investigated. The method is applied to a segment of an infinite tube for which the linear analytical solution is available. The characteristics of the velocity wave calculated from an input pressure wave are presented as departures from the linear theory values of these characteristics, the wave speed, flux and transmission factor per wavelength. Computations are made at values of non-dimensional frequency (Stokes number α) of about 3 and 10. It is concluded that as far as physiological application is concerned (i.e. small amplitude and long wavelength) the results of linear theory are a very good first approximation for the cylindrical tube. At α=10, the relative departure of wave speed is about 0·5 times the relative diameter amplitude ( $${{\hat D} \mathord{\left/ {\vphantom {{\hat D} {\bar D}}} \right. \kern-\nulldelimiterspace} {\bar D}}$$ amplitude/mean diameter) when the pressure-radius relation is linear and the pressure and velocity waves have the same characteristics. At α=3 the corresponding wave speed departure is about 0·1 $${{\hat D} \mathord{\left/ {\vphantom {{\hat D} {\bar D}}} \right. \kern-\nulldelimiterspace} {\bar D}}$$ . The relative departure of the flux is less than 0·05 $${{\hat D} \mathord{\left/ {\vphantom {{\hat D} {\bar D}}} \right. \kern-\nulldelimiterspace} {\bar D}}$$ at α=3 and about 0·5 $${{\hat D} \mathord{\left/ {\vphantom {{\hat D} {\bar D}}} \right. \kern-\nulldelimiterspace} {\bar D}}$$ at α=10. The transmission coefficient has a relative departure of less than 0·05 $${{\hat D} \mathord{\left/ {\vphantom {{\hat D} {\bar D}}} \right. \kern-\nulldelimiterspace} {\bar D}}$$ at α=10 and its relative increase at α=3 is about 0·3 $${{\hat D} \mathord{\left/ {\vphantom {{\hat D} {\bar D}}} \right. \kern-\nulldelimiterspace} {\bar D}}$$ . [ABSTRACT FROM AUTHOR]

The one-dimensional equations are used in the calculation of blood flow in arteries. The majority of the treatments use the method of characteristics and because of the nature of the method it is necessary to use a simplified value of the skin friction. A commonly used simplification is to assume the zero frequency value of the skin friction. The effect of the use of this approximation is compared with results using the full linear theory value. It is shown that the phase difference between the skin friction and the flux has an appreciable effect on the velocity wave calculated from a given pressure wave. [ABSTRACT FROM AUTHOR]

Dihydrodipicolinate synthase (DHDPS) is an essential enzyme involved in the lysine biosynthesis pathway. DHDPS from E. coli is a homotetramer consisting of a 'dimer of dimers', with the catalytic residues found at the tight-dimer interface. Crystallographic and biophysical evidence suggest that the dimers associate to stabilise the active site configuration, and mutation of a central dimer-dimer interface residue destabilises the tetramer, thus increasing the flexibility and reducing catalytic efficiency and substrate specificity. This has led to the hypothesis that the tetramer evolved to optimise the dynamics within the tight-dimer. In order to gain insights into DHDPS flexibility and its relationship to quaternary structure and function, we performed comparative Molecular Dynamics simulation studies of native tetrameric and dimeric forms of DHDPS from E. coli and also the native dimeric form from methicillin-resistant Staphylococcus aureus (MRSA). These reveal a striking contrast between the dynamics of tetrameric and dimeric forms. Whereas the E. coli DHDPS tetramer is relatively rigid, both the E. coli and MRSA DHDPS dimers display high flexibility, resulting in monomer reorientation within the dimer and increased flexibility at the tight-dimer interface. The mutant E. coli DHDPS dimer exhibits disorder within its active site with deformation of critical catalytic residues and removal of key hydrogen bonds that render it inactive, whereas the similarly flexible MRSA DHDPS dimer maintains its catalytic geometry and is thus fully functional. Our data support the hypothesis that in both bacterial species optimal activity is achieved by fine tuning protein dynamics in different ways: E. coli DHDPS buttresses together two dimers, whereas MRSA dampens the motion using an extended tight-dimer interface. INSET: Author Summary. [ABSTRACT FROM AUTHOR]

Diabet. Med. 27, 150–156 (2010) Aims Peroxisome proliferator-activated receptor (PPAR)-γ and PPAR-α agonists individually reduce intra-organ triglyceride content and improve insulin sensitivity. However, the precise effects of combined PPAR-γ and PPAR-α therapy on intra-organ triglyceride content and insulin sensitivity in subjects with Type 2 diabetes have not yet been determined. Methods Diet-controlled Type 2 subjects ( n = 9) were studied before and after 16 weeks of combined PPAR-γ [pioglitazone (PIO), 45 mg daily] and PPAR-α [bezafibrate (BEZA), modified release 400 mg daily] agonist therapy. Glucose metabolism and endogenous glucose production were measured following a standard liquid test meal. Liver and muscle triglyceride levels were measured by 1H magnetic resonance spectroscopy. Results Combined PIO and BEZA therapy reduced mean fasting (7.5 ± 0.5 vs. 6.5 ± 0.2 mmol/l, P = 0.04) and peak postprandial plasma glucose (15.3 ± 1.1 vs. 11.7 ± 0.6 mmol/l, P = 0.007). No significant change in hepatic or muscle triglyceride content was observed. Postprandial suppression of endogenous glucose production remained similar on both study days. Both subcutaneous and visceral fat content increased following therapy. Conclusions Combined PIO and BEZA therapy in Type 2 diabetes does not decrease intrahepatic triglyceride content or postprandial endogenous glucose production. This study demonstrates an unexpected adverse interaction of PPAR-α with PPAR-γ agonist therapy. [ABSTRACT FROM AUTHOR]

Abortion is one of the most divisive topics in healthcare. Proponents and opponents hold strong views. Some health workers who oppose abortion assert a right of conscientious objection to it, a position itself that others find unethical. Even if allowance for objection should be made, it is not clear how far it should extend. Can conscientious objection be given as a reason not to refer when a woman requests her doctor to do so? This paper explores the idea of the general practitioner (GP) who declines to make a direct referral for abortion, asking the woman to see another GP instead. The purpose is to defend the claim that an appeal to conscientious objection in this way can be reasonable and ethical. [ABSTRACT FROM AUTHOR]

Copyright of Surface Coatings International Part B: Coatings Transactions is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

f.l. low, i.c. shaw and j.a. gerrard. 2004.To investigate the ability of baker's yeast (Saccharomyces cerevisiae) to degrade the herbicide glyphosate during the fermentation cycle of the breadmaking process.Aqueous glyphosate was added to bread ingredients and kneaded by commercially available breadmaking equipment into dough cultures. Cultures were incubated in the breadmaker throughout the fermentation cycle. The recovery of glyphosate levels following fermentation was determined, thus allowing an estimation of glyphosate degradation by yeast.It was shown, for the first time, thatS. cerevisiaeplays a role in metabolizing glyphosate during the fermentation stages of breadmaking. Approximately 21% was degraded within 1 h.As a result of projected increases in the glyphosate use on wheat and the role of bread as a dietary staple, this may contribute to more informed decisions being made relating to the use of glyphosate on glyphosate-resistant wheat, from a public health/regulatory perspective. [ABSTRACT FROM AUTHOR]

The thermal and pH stabilities of cypermethrin during food processing were investigated using tomato as a model food system and high-performance liquid chromatography as the analytical method. Cypermethrin was thermally unstable in aqueous conditions, where the hydrolysis of the pesticide was accelerated by heat. The mean proportion remaining after heating cypermethrin in water for 10 min was 66%, falling to 27% after 1 h. Similarly, thermal processing of canned tomatoes caused cypermethrin to degrade, with remaining levels in the final product ranging from 30 to 60% of the original. Cypermethrin was unstable at extreme pHs, with acid hydrolysis occurring faster than alkaline hydrolysis in phosphate buffers. The acidity of tomato paste (pH 4.3) caused cypermethrin levels to decrease by 30% within 12 days at 5°C. The studies indicate that cypermethrin residues are likely to degrade by hydrolysis during food processing, thus reducing the exposure of consumers to cypermethrin. 3-Phenoxybenzaldehyde, a hydrolysis breakdown product of cypermethrin, was detected in the tomato paste and from the heating of cypermethrin in water at 100°C. There is concern that the risk of breakdown products in terms of endocrine activity is unknown since in vitro studies reported that cypermethrin breakdown products display endocrine activity. [ABSTRACT FROM AUTHOR]

Postnatal depression is a common problem for women and for their families. Research has provided the evidence for successful early intervention programmes. If this research is now going to benefit more women, researchers must be involved in dissemination beyond journal publication. This paper provides a preliminary assessment of dissemination via trainer training, in particular to answer three questions: 1) Do the teams of mental health and primary care professionals actually provide training to health visitors and others? 2) Do the health visitors then adopt protocols consistent with the evidence-based recommendations in training? 3) Can barriers to implementation be identified? Seventy-three of the 113 respondents had run training and a further 24 had provided some form of education on postnatal depression. The trainers reported systems chosen by trainees that were in line with the available evidence. Barriers to training included the loss of a team member due to job changes, and lack of management support for the provision of time and resources. Eleven teams had audited services after training. The National Screening Committee now recommends that all local implementations of screening for postnatal depression should be embedded in the research process to ensure that women are helped not harmed. The importance of the support of specialist local trainers in this process has not been properly addressed or the impact on effectiveness evaluated in an RCT. [ABSTRACT FROM AUTHOR]

Transglutaminase is a crosslinking enzyme that is finding increasing use in foods, yet the molecular changes responsible for its effects are not fully understood. Proteins were extracted from bread and croissant doughs that had been treated with transglutaminase and compared to those from control doughs by size exclusion high performance liquid chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis. Transglutaminase increased the amount of protein extracted in the gliadin fraction in both bread and croissant doughs. In croissant doughs, a corresponding decrease in the protein extracted in the albumin to globulin fraction was seen. In each case, crosslinking of the high molecular weight glutenins was observed. The possible role of each of these changes on the functional properties of baked products is discussed. [ABSTRACT FROM AUTHOR]

Many studies have documented major landslide events in mountain areas following heavy rainfall amounts. In the Himalaya, landslides occur during every monsoon period, but the role of rainfall in triggering these failures is not clear. This paper reports the results of a three-year study (1991-1993) into landsliding in the Likhu Khola drainage basin, Middle Hills, Nepal. Considerable annual variability in numbers, types and sizes of landslides was noted. Some of this variability can be explained by fluctuations in rainfall amounts and intensities, but many landslides were explained more easily by other controlling factors. In situations where slopes are extensively terraced for agriculture, with some terraces being intensely irrigated and others not, relationships between landsliding and rainfall amounts are complex and no simple explanations can be made. [ABSTRACT FROM AUTHOR]

Copyright of Medical & Biological Engineering & Computing is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Medical & Biological Engineering & Computing is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The displacement relationships describing the deformation of an elastic vessel under excess internal pressure which are derived from different theories of elasticity are compared. The main result of the comparison is that theories which take account of the thickness of the wall of the vessel produce a significantly better representation than those theories which treat the wall as a membrane. The classical and statistical theories of thick-walled tubes result in complicated pressure-radius relationships. It is shown that there is little difference between the results of the more exact theories and those for a thin membrane corrected by means of a simple thickness factor. A review of the different theories is necessary to decide which pressure-displacement relationship to apply as an approximation for the elastic properties of arteries. An indication is given of the manner in which the relationship is used in numerical computations. In Part 2 the experimental determination of the pressure-radius relationship for a rubber tube is described. The results are in agreement with the conclusions of the comparison of theoretical treatments in Part 1. [ABSTRACT FROM AUTHOR]

Cord and maternal blood samples were obtained at delivery in 25 normal and 14 diabetic pregnancies (13 insulindependent, one gestational). Total glycosylated haemoglobin, measured by the colorimetric thiobarbiturate method (mmol hydroxymethylfurfural/mol haemoglobin), was lower in cord than maternal blood (mean 18.7±1.7 versus 26.5±2.1, mean ± SD, p<0.001). Glycosylated haemoglobin was higher following diabetic pregnancies, both in cord (diabetic 19.9± 1.6 versus normal 17.9±1.4, p<0.001) and maternal samples (diabetic 27.7±1.5 versus normal 25.6±2.1, p<0.005). Cord and maternal glycosylated haemoglobin correlated in the normal ( r=0.60, p<0.01) but not in the diabetic group ( r=0.02, NS). Birth weight ratio was higher in infants of diabetic than of normal mothers (1.10±0.16 versus 0.99±0.13, p< 0.05) but failed to correlate with cord or maternal glycosylated haemoglobin or, in the diabetic group, with mean blood glucose. [ABSTRACT FROM AUTHOR]

Fatty acid compositions were determined of phospholipids, isolated from umbilical arteries and veins, obtained from Dutch neonates after vaginal delivery, terminating normal pregnancy. The fatty acid profiles of the cord vessels were characterized by the absence of eicosapentaenoic (timnodonic) acid, a low (2-3%) content of linoleic acid and reasonable amounts of arachidonic acid (10-15%) and docosahexaenoic (cervonic) acid (3-5%). Significant amounts of Mead acid (1-4%) and its direct elongation product (0.5-2%) were also observed. In each cord, the efferent blood vessels contained significantly more Mead acid and other fatty acids of the oleic acid (n−9) family and less fatty acids of the linoleic (n−6) and linolenic (n−3) families than the afferent blood vessel. This indicates that the essential fatty acid (EFA) status of 'downstream' neonatal tissue may be marginal. No signs of EFA-deficiency were observed in endothelial and smooth muscle cells in culture, or in blood vessels from adults. In all cords 22∶5(n−6) was significantly higher in the artery compared to the vein, whereas for all other (n−6) fatty acids this difference was negative. Since the synthesis of 22∶5(n−6) is known to be stimulated when the required amount of cervonic acid, 22∶6(n−3), is too low, our observations also suggest that the cervonic acid status of the neonates investigated was not optimal. Further studies are in progress to relate these findings to maternal EFA status and complications of pregnancy. [ABSTRACT FROM AUTHOR]

The familial resemblance for immunoglobulin A, D, E, G, and M levels was investigated with family data collected in Canada and the U.S., entertaining both multifactorial and single gene hypotheses. Significant familial effects were found for each of the immunoglobulins, and there was significant support for a major gene hypothesis for IgA and IgD levels. Whereas there have been several reports suggesting a major gene determinant for IgE levels, including that from our own Canadian study, analysis of the U.S. sample suggested that a multifactorial component parsimoniously explained the observed familial resemblance. [ABSTRACT FROM AUTHOR]

It has been reported that lymphocytes from peripheral blood (PBL) cultured with interleukin-2 (IL-2) produce predominantly CD16+ lymphokine-activated killer (LAK) cells. We developed a two-step method to generate LAK cells from human PBL in long-term cultures (10-12 days) with recombinant human IL-2 (rhIL-2) and characterized the evolving LAK cell population by testing its phenotype and cytotoxic activity as a function of time. The starting PBL displayed some natural killer (NK) cytotoxicity but no LAK activity. At day 6. the cells were a mixed population of about 80% CD3+ and 6% CD16+ cells. Little proliferation was evident but strong LAK activity was detected. After 10- 12 days, major cell expansion had occurred and they were essentially a pure (>90%) CD3, CD16 CD56 cell population large granular lymphocyte (LGL) by morphology that displayed strong non-MHC-restricted killing activity (>200 lytic units). Over the same period of time, the CD16+ cells had almost completely regressed in these cultures. This preferential induction of CD+ LAK cells was not an effect of IL-2 concentration as 10 U/ml was as effective as 500 U/ml. Further characterization revealed a major population of CD4+ (60%) and CD8+ CD8 (30%> with a smaller fraction (<9%) of γδ cells. These results indicate that a virtually pure CD3+ LAK cells population was produced with long-term cultures of lymphocytes from peripheral blood in rhIL-2, in which active proliferation of the CD3+ but not CD16+ cells occurred. [ABSTRACT FROM AUTHOR]

Serum-immunoglobulin levels (IgG, IgM, IgA, IgD and IgE) have been studied in white and metis (Cree Indian) communities in Saskatchewan. The levels of IgG, IgA, IgD and IgE were higher in the metis than in the whites. Both IgG and IgM were higher in females than in males. IgG and IgA levels rose progressively with age. IgM levels rose rapidly during the first year to almost adult levels, and then fell gradually alter the age of 30. IgE levels also rose rapidly during the first 3 years of life, were higher on average in children than in adults, and fell to adult levels at puberty. Low levels of IgA were associated with high levels of IgG; they were not associated with tither high levels of IgE or an increase in the prevalence of asthma. [ABSTRACT FROM AUTHOR]

The cleavage of pooled human IgG and IgG1, IgG2, and IgG3 myeloma proteins with α-chymotrypsin has been studied. The products of digestion were analyzed by starch gel electrophoresis and fractionated by gel filtration. In addition to low molecular weight peptides an electrophotetically fast fragment from the Cγ3 homology region (ctFc′) was detected in all cases. Pooled IgG, IgG1, and IgG3 proteins yielded appreciable amounts of an Fab-like fragment. Finally, various high molecular weight fragments were released that appeared to resemble recently described fragments produced by papain. These were Fab/c-like fragments from pooled IgG and IgG1, F(ab)2-like fragments from IgG2, and Fch-like fragments from IgG3. [ABSTRACT FROM AUTHOR]

Health visitors in North Staffordshire, Edinburgh and Lewisham were given the opportunity to participate in a training programme in the detection, treatment and pervention of postnatal depression, based on previously reported successful intervention strategies. They were trained in the use of the Edinburgh Postnatal Depression Scale(EPDS), and given information about the value and practice of non-directive counselling and about preventative strategies. Knowledge acquisition was evaluation by self-report questionnaires given before and after training. The health visitors were encouraged to screen postnatal women at three specific times using the EPDS and to offer non-directive counselling to women who obtained high scores. A baseline measure of the incidence of postnatal depression was obtained by asking health visitors to give an EPDS form to all women in their caseload with a 6-month-old baby before training commenced. A comparison of the number of women with high EPDS scores at 6 months postnatally, before and after training, showed that participation in the programme enabled health visitors to positively influence the emotional well-being of postnatal women. These results have implications for the role of health visitors which is currently being challenged, as well as for components of their training and continuing professional development. [ABSTRACT FROM AUTHOR]

Many European countries test cars, but not their drivers, as they age. There is evidence to suggest that human factors are more important than vehicular factors as causes of motor crashes. The elderly also are involved in more accidents per distance travelled than middle-aged drivers. As the UK relies on self-certification of health by drivers over the age of 70 years, we examined the driving practices of patients with dementia attending a Memory Clinic. Nearly one-fifth of 329 patients with documented dementia continued to drive after the onset of dementia, and impaired driving ability was noted in two-thirds of these. Their families experienced great difficulty in persuading patients to stop driving, and had to invoke outside help in many cases. Neuropsychological tests did not help to identify those who drove badly while activity of daily living scores were related to driving ability. These findings suggest that many patients with dementia drive in an unsafe fashion after the onset of the illness. The present system of self-certification of health by the elderly for driver-licensing purposes needs to be reassessed. [ABSTRACT FROM AUTHOR]

Many European countries test cars, but not their drivers, as they age. There is evidence to suggest that human factors are more important than vehicular factors as causes of motor crashes. The elderly also are involved in more accidents per distance travelled than middle-aged drivers. As the UK relies on self-certification of health by drivers over the age of 70 years, we examined the driving practices of patients with dementia attending a Memory Clinic. Nearly one-fifth of 329 patients with documented dementia continued to drive after the onset of dementia, and impaired driving ability was noted in two-thirds of these. Their families experienced great difficulty in persuading patients to stop driving, and had to invoke outside help in many cases. Neuropsychological tests did not help to identify those who drove badly while activity of daily living scores were related to driving ability. These findings suggest that many patients with dementia drive in an unsafe fashion after the onset of the illness. The present system of self-certification of health by the elderly for driver-licencing purposes needs to be reassessed. [ABSTRACT FROM AUTHOR]

Copyright of Microchimica Acta is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)