Amino Acid Analysis of Marine Sediments, Hauraki Gulf, New Zealand

Amino acid compositions, bulk organic carbon, total nitrogen, and total organic matter were measured for eight sediment samples from the Hauraki Gulf, New Zealand, in order to assess the source and fate of organic matter in a shallow marine environment. Samples were collected from near-shore and off-shore shore sites, as well as from a site receiving freshwater input from multiple rivers. A comparison of carbon, nitrogen, and amino acid compositions of samples between 1 cm depth (Uhle 2004) and 5 cm depth was used to assess changes in organic matter composition through time. Amino acid analyses in particular should be effective in deciphering organic decomposition through both the presence and abundance of amino acids. C:N values, which range from 6.5-9.3, are typical for marine sediments and indicate that the primary source for organic matter is marine despite potential terrigenous input from the surrounding environment. This interpretation is supported by carbon isotopes (-20‰ and -22‰ for most sites) which is typical for marine-derived organic materials. C:N ratios do not appreciably vary from 1-5 cm depth, suggesting that there has not been significant depletion of organic matter in these young deposits. Furthermore, both D- and L-amino acids are present at 5 cm depth, supporting minimal organic matter decomposition. However, concentrations of amino acid decreases with depth, and the presence of D-alanine, D-aspartic acid, D-glutamic acid, glycine, and non-protein amino acids, at 5 cm depth, suggests at least a small contribution to the organic carbon source from bacteria. A decrease in δ15N with depth further suggests the possibility of bacterial reworking under anoxic conditions. Combined, these results support hypotheses of microbial reworking of organic matter through time, but are not clearly diagnostic of this process

Galerkin approximations for initial value problems with known end time conditions

AbstractGalerkin's method is used to approximate the transient solutions of intial value problems in which a steady state or advanced time state is known. A convergence theorem is established and choices of basis functions are discussed. The method is then applied to systems arising from nuclear reactor kinetics theory and the semi-discretization of parabolic two-point boundary value problems

Superconducting properties of the In-substituted topological crystalline insulator, SnTe

We report detailed investigations of the properties of a superconductor obtained by substituting In at the Sn site in the topological crystalline insulator (TCI), SnTe. Transport, magnetization and heat capacity measurements have been performed on crystals of Sn$_{0.6}$In$_{0.4}$Te, which is shown to be a bulk superconductor with $T_c^{\rm{onset}}$ at $\sim4.70(5)$~K and $T_c^{\rm{zero}}$ at $\sim3.50(5)$~K. The upper and lower critical fields are estimated to be $\mu_0H_{c2}(0)=1.42(3)$~T and $\mu_0H_{c1}(0)=0.90(3)$~mT respectively, while $\kappa=56.4(8)$ indicates this material is a strongly type II superconductor

Rates of symptom reoccurrence after endovascular therapy in subclavian artery stenosis and prevalence of subclavian artery stenosis prior to coronary artery bypass grafting

Percutaneous transluminal angioplasty (PTA) and stenting is commonly used to treat subclavian artery stenosis (SAS). In this study, the outcomes of 43 consecutive cases, performed at one institution from October 1997 to October 2005, were analyzed. Mean stenosis was 84.41% pre-intervention and 6.83% post-intervention. Five of the procedures were angioplasty alone; 38 were angioplasty with stenting. Technical success was achieved in 42 out of 43 patients. The 30-day mortality rate was 0%. At one-month post intervention, all patients were symptom free. Ten patients redeveloped symptoms by one year. Demographic data, patient comorbidities, and indication to treat were analyzed. It was found that prior coronary intervention led to a statistically significant higher rate of symptom reoccurrence (p = 0.036). Additionally, a divergence in the rate of symptom reoccurrence based on indication to treat SAS was noted with the highest rate of symptom reoccurrence in the pre-coronary artery bypass grafting (CABG) group and the lowest rate of symptom reoccurrence in the subclavian steal syndrome (SSS) group. The coronary subclavian steal (CSS) group had an intermediate rate of symptom reoccurrence. During this time period, 1154 CABGs were performed. Flow-limiting stenosis was noted on angiography in 17 of these patients, giving pre-CABG prevalence of 1.46%

Vitalism in Early Modern Medical and Philosophical Thought

Vitalism is a notoriously deceptive term. It is very often defined as the view, in biology, in early modern medicine and differently, in early modern philosophy, that living beings differ from the rest of the physical universe due to their possessing an additional ‘life-force’, ‘vital principle’, ‘entelechy’, enormon or élan vital. Such definitions most often have an explicit pejorative dimension: vitalism is a primitive or archaic view, that has somehow survived the emergence of modern science (the latter being defined in many different ways, from demystified Cartesian reductionism to experimental medicine, biochemistry or genetics: Cimino and Duchesneau eds. 1997, Normandin and Wolfe eds. 2013). Such dismissive definitions of vitalism are meant to dispense with argument or analysis. Curiously, the term has gained some popularity in English-language scholarship on early modern philosophy in the past few decades, where it is used without any pejorative dimension, to refer to a kind of ‘active matter’ view, in which matter is not reducible to the (mechanistic) properties of size, shape and motion, possessing instead some internal dynamism or activity (see e.g. James 1999, Boyle 2018, Borcherding forthcoming). The latter meaning is close to what the Cambridge Platonist Ralph Cudworth termed ‘hylozoism’, namely the attribution of life, agency or mind to matter, and he implicitly targeted several figures I shall mention here, notably Margaret Cavendish and Francis Glisson, for holding this view. However, one point I shall make in this entry is that when vitalism first appears by name, and as a self-designation, in the Montpellier School (associated with the Faculty of Medicine at the University of Montpellier, in the second half of the eighteenth century; thus vitalisme appears first, followed shortly thereafter by Vitalismus in German, with ‘vitalism’ appearing in English publications only in the early nineteenth century: Toepfer 2011), it is quite different from both the more ‘supernatural’ view described above – chiefly espoused by its rather obsessive opponents – and from the more neutral, but also de-biologized philosophical view (that of e.g. Cavendish or Conway who are, broadly speaking naturalists). Rather than appealing to a metaphysics of vital force, or of self-organizing matter, this version of vitalism, which I shall refer to as ‘medical vitalism’, seems to be more of a ‘systemic’ theory: an attempt to grasp and describe top-level (‘organizational’, ‘organismic’, ‘holistic’) features of living systems (Wolfe 2017, 2019). In this entry I seek to introduce some periodization in our thinking about early modern (and Enlightenment) vitalism, emphasizing the difference between the seventeenth-century context and that of the following generations – culminating in the ideas of the Montpellier School. This periodization should also function as a kind of taxonomy or at least distinction between some basic types of vitalism. As I discuss in closing, these distinctions can cut across the texts and figures we are dealing with, differently: metaphysical vs. non-metaphysical vitalism, philosophical vs. medical vitalism, medical vs. ‘embryological’ vitalism, and so on. A difference I can only mention but not explore in detail is that the more medically grounded, ‘organismic’ vitalism is significantly post-Cartesian while the more biological/embryological vitalism is, inasmuch as it is a dynamic, self-organizing matter theory, an extension of Renaissance ideas (chymiatry, Galenism and in general theories of medical spirits). I examine successively vitalism’s Renaissance prehistory, its proliferation as ‘vital matter theory’ in seventeenth-century England (in authors such as Cavendish, Conway and Glisson, with brief considerations on Harvey and van Helmont), and its mature expression in eighteenth-century Montpellier (notably with Bordeu and Ménuret de Chambaud)

Role of Sigma-1 Receptors in Neurodegenerative Diseases

Neurodegenerative diseases with distinct genetic etiologies and pathological phenotypes appear to share common mechanisms of neuronal cellular dysfunction, including excitotoxicity, calcium dysregulation, oxidative damage, ER stress and mitochondrial dysfunction. Glial cells, including microglia and astrocytes, play an increasingly recognized role in both the promotion and prevention of neurodegeneration. Sigma receptors, particularly the sigma-1 receptor subtype, which are expressed in both neurons and glia of multiple regions within the central nervous system, are a unique class of intracellular proteins that can modulate many biological mechanisms associated with neurodegeneration. These receptors therefore represent compelling putative targets for pharmacologically treating neurodegenerative disorders. In this review, we provide an overview of the biological mechanisms frequently associated with neurodegeneration, and discuss how sigma-1 receptors may alter these mechanisms to preserve or restore neuronal function. In addition, we speculate on their therapeutic potential in the treatment of various neurodegenerative disorders

Precision Measurement of the Newtonian Gravitational Constant Using Cold Atoms

About 300 experiments have tried to determine the value of the Newtonian gravitational constant, G, so far, but large discrepancies in the results have made it impossible to know its value precisely. The weakness of the gravitational interaction and the impossibility of shielding the effects of gravity make it very difficult to measure G while keeping systematic effects under control. Most previous experiments performed were based on the torsion pendulum or torsion balance scheme as in the experiment by Cavendish in 1798, and in all cases macroscopic masses were used. Here we report the precise determination of G using laser-cooled atoms and quantum interferometry. We obtain the value G=6.67191(99) x 10^(-11) m^3 kg^(-1) s^(-2) with a relative uncertainty of 150 parts per million (the combined standard uncertainty is given in parentheses). Our value differs by 1.5 combined standard deviations from the current recommended value of the Committee on Data for Science and Technology. A conceptually different experiment such as ours helps to identify the systematic errors that have proved elusive in previous experiments, thus improving the confidence in the value of G. There is no definitive relationship between G and the other fundamental constants, and there is no theoretical prediction for its value, against which to test experimental results. Improving the precision with which we know G has not only a pure metrological interest, but is also important because of the key role that G has in theories of gravitation, cosmology, particle physics and astrophysics and in geophysical models.Comment: 3 figures, 1 tabl

Organisational participation and women - an attitude problem?

Employee participation is a dynamic and contested area of organisational behaviour, attracting continuing academic, practitioner and policy interest and debate. This chapter focuses on organisational participation and women

Psychometric Evaluation of the Arabic Version of the Spiritual Well-Being Scale on a Sample of Jordanian Arab Christians

This paper assesses the psychometric properties of the Arabic version of the Spiritual Well-Being Scale (SWBS) in an Arab Christian sample by analyzing its internal structure. A convenience sample of 340 Arab Christians was recruited from the adult community population of northern Jordan. Data were collected through a self-completion, anonymous questionnaire distributed through church and community groups. Principal Components factor analysis, non-parametric bivariate statistics, and Cronbach's alpha were used to assess the psychometric properties of the total scale and its subscales. The findings broadly supported the factor structure of the SWBS in other Arab samples in that the scale consists of three factors, representing positive existential well-being, affiliation, and alienation subscales. In conclusion, these preliminary findings suggest that the Arabic version of the SWBS can be used as an instrument to measure levels of spiritual well-being in Arab Christian populations. </jats:p