Wear and its effects on dental topography measures in howling monkeys (Alouatta palliata).

OBJECTIVES: Three dental topography measurements: Dirichlet Normal Energy (DNE), Relief Index (RFI), and Orientation Patch Count Rotated (OPCR) are examined for their interaction with measures of wear, within and between upper and lower molars in Alouatta palliata. Potential inferences of the "dental sculpting" phenomenon are explored. MATERIALS AND METHODS: Fifteen occluding pairs of howling monkey first molars (15 upper, 15 lower) opportunistically collected from La Pacifica, Costa Rica, were selected to sample wear stages ranging from unworn to heavily worn as measured by the Dentine Exposure Ratio (DER). DNE, RFI, and OPCR were measured from three-dimensional surface reconstructions (PLY files) derived from high-resolution CT scans. Relationships among the variables were tested with regression analyses. RESULTS: Upper molars have more cutting edges, exhibiting significantly higher DNE, but have significantly lower RFI values. However, the relationships among the measures are concordant across both sets of molars. DER and EDJL are curvilinearly related. DER is positively correlated with DNE, negatively correlated with RFI, and uncorrelated with OPCR. EDJL is not correlated with DNE, or RFI, but is positively correlated with OPCR among lower molars only. DISCUSSION: The relationships among these metrics suggest that howling monkey teeth adaptively engage macrowear. DNE increases with wear in this sample presumably improving food breakdown. RFI is initially high but declines with wear, suggesting that the initially high RFI safeguards against dental senescence. OPCR values in howling monkey teeth do not show a clear relationship with wear changes.

Introducing molaR: a New R Package for Quantitative Topographic Analysis of Teeth (and Other Topographic Surfaces)

© 2016 Springer Science+Business Media New YorkResearchers studying mammalian dentitions from functional and adaptive perspectives increasingly have moved towards using dental topography measures that can be estimated from 3D surface scans, which do not require identification of specific homologous landmarks. Here we present molaR, a new R package designed to assist researchers in calculating four commonly used topographic measures: Dirichlet Normal Energy (DNE), Relief Index (RFI), Orientation Patch Count (OPC), and Orientation Patch Count Rotated (OPCR) from surface scans of teeth, enabling a unified application of these informative new metrics. In addition to providing topographic measuring tools, molaR has complimentary plotting functions enabling highly customizable visualization of results. This article gives a detailed description of the DNE measure, walks researchers through installing, operating, and troubleshooting molaR and its functions, and gives an example of a simple comparison that measured teeth of the primates Alouatta and Pithecia in molaR and other available software packages. molaR is a free and open source software extension, which can be found at the doi:10.13140/RG.2.1.3563.4961(molaR v. 2.0) as well as on the Internet repository CRAN, which stores R packages.

Glycemic State Regulates Brain-Derived Neurotrophic Factor Responsiveness of Neurons in the Paraventricular Nucleus of the Hypothalamus

Brain derived neurotrophic factor (BDNF) is a member of the family of neurotrophins and binds to the tropomyosin-related kinase B (TrkB) receptor. Like other neurotrophic factors, BDNF is involved in the development and differentiation of neurons. Recently, studies have suggested important roles for BDNF in the regulation of energy homeostasis. The paraventricular nucleus (PVN) is critical for normal energy balance contains high levels of both BDNF and TrkB mRNA. Studies have shown that microinjections of BDNF into the PVN increase energy expenditure, suggesting BDNF plays a role in energy homeostasis through direct actions in this hypothalamic nucleus. We used male Sprague-Dawley rats to perform whole-cell current-clamp experiments from PVN neurons in slice preparation. BDNF was bath applied at a concentration of 2nM and caused depolarizations in 54% of neurons (n = 25; mean change in membrane potential: 8.9 ± 1.2 mV), hyperpolarizations in 23% (n = 11; mean change in membrane potential: -6.7 ± 1.4 mV), while the remaining cells tested were unaffected. Previous studies showing effects of BDNF on γ-aminobutyric acid type A (GABAA) mediated neurotransmission in PVN led us to examine if these BDNF-mediated changes in membrane potential were maintained in the presence of tetrodotoxin (TTX) sodium channel blocker (N = 9; 56% depolarized, 22% hyperpolarized, 22% non-responders) and bicuculline (GABAA antagonist) (N = 12; 42% depolarized, 17% hyperpolarized, 41% non-responders), supporting the conclusion that these effects on membrane potential were postsynaptic. We also evaluated the effects of BDNF on these neurons across varying physiologically relevant extracellular glucose concentrations. At 10 mM 23% (n = 11; mean: -6.7 ± 1.4 mV) of PVN neurons hyperpolarized in response to BDNF treatment, whereas at 0.2 mM glucose, 71% showed hyperpolarizing effects (n = 12; mean: -6.3 ± 2.8 mV). Our findings reveal that BDNF has direct impacts on PVN neurons and that these neurons are capable of integrating multiple sources of metabolically relevant input. Our analysis regarding glucose concentrations and their effects on these neurons’ response to other metabolic signals emphasizes the importance of using physiologically relevant conditions for study of central pathways involved in the regulation of energy homeostasis.

Evolutionäre Veränderungen in der Nutzung redox-aktiver Aminosäuren und ihre Ursachen

Gewebe, Zellen und speziell Zellkompartimente unterscheiden sich in ihrer Sauerstoffkonzentration, Stoffwechselrate und in der Konzentration an gebildeten reaktiven Sauerstoffspezies. Um eine mögliche Änderung in der Aminosäurennutzung durch den Einfluss von Sauerstoff und seinen reaktiven Spezies untersuchen zu können wurden, Bereiche bzw. Kompartimente der menschlichen Zelle definiert, die einen Referenzrahmen bildeten und bekannt dafür sind, einen relativ hohen Grad an reaktiven Sauerstoffspezies aufzuweisen. Aus dem Vergleich wurde deutlich, dass vor allem die beiden redox-aktiven und schwefeltragenden Aminosäuren Cystein und Methionin durch eine besondere Verteilung und Nutzung charakterisiert sind. Cystein ist hierbei diejenige Aminosäure mit den deutlichsten Änderungen in den fünf untersuchten Modellen der oxidativen Belastung. In all diesen Modellen war die Nutzung von Cystein deutlich reduziert, wohingegen Methionin in Proteinen des Mitochondriums und der Elektronentransportkette angereichert war. Dieser auf den ersten Blick paradoxe Unterschied zwischen Cystein und Methionin wurde näher untersucht, indem die differenzierte Methioninnutzung in verschiedenen Zellkompartimenten von Homo sapiens charakterisiert wurde.rnDie sehr leicht zu oxidierende Aminosäure Methionin zeigt ein ungewöhnliches Verteilungsmuster in ihrer Nutzungshäufigkeit. Entgegen mancher Erwartung wird Methionin in zellulären Bereichen hoher oxidativer Belastung und starker Radikalproduktion intensiv verwendet. Dieses Verteilungsmuster findet man sowohl im intrazellulären Vergleich, als auch im Vergleich verschiedener Spezies untereinander, was daraufhin deutet, dass es einen lokalen Bedarf an redox-aktiven Aminosäuren gibt, der einen sehr starken Effekt auf die Nutzungshäufigkeit von Methionin ausübt. Eine hohe Stoffwechselrate, die im Allgemeinen mit einer erhöhten Produktion von Oxidantien assoziiert wird, scheint ein maßgeblicher Faktor der Akkumulation von Methionin in Proteinen der Atmungskette zu sein. Die Notwendigkeit, oxidiertes Antioxidans wieder zu reduzieren, findet auch bei Methionin Anwendung, denn zu Methioninsulfoxid oxidiertes Methionin wird durch die Methioninsulfoxidreduktase wieder zu Methionin reduziert. Daher kann die spezifische Akkumulation von Methionin in Proteinen, die verstärkt reaktiven Sauerstoffspezies ausgesetzt sind, als eine systematische Strategie angesehen werden, um andere labile Strukturen vor ungewollter Oxidation zu schützen. rnDa Cystein in allen untersuchten Modellen der oxidativen Belastung und im Besonderen in Membranproteinen der inneren Mitochondrienmembran lebensspannenabhängig depletiert war, wurde dieses Merkmal näher untersucht. Deshalb wurde die Hypothese getestet, ob ein besonderer Redox-Mechanismus der Thiolfunktion für diese selektive Depletion einer im Allgemeinen als harmlos oder antioxidativ geltenden Aminosäure verantwortlich ist. Um den Effekt von Cysteinresten in Membranen nachzustellen, wurden primäre humane Lungenfibroblasten (IMR90) mit diversen Modellsubstanzen behandelt. Geringe Konzentrationen der lipophilen Substanz Dodecanthiol verursachten eine signifikante Toxizität in IMR90-Zellen, die von einer schnellen Zunahme an polyubiquitinierten Proteinen und anderen Indikatoren des proteotoxischen Stresses, wie Sequestosom 1 (P62), HSP70 und HSP90 begleitet wurde. Dieser Effekt konnte spezifisch der Chemie der Thiolfunktion in Membranen zugeordnet werden, da Dodecanol (DOH), Dodecylmethylsulfid (DMS), Butanthiol oder wasserlösliche Thiole weder eine cytotoxische Wirkung noch eine Polyubiquitinierung von Proteinen verursachten. Die Ergebnisse stimmen mit der Hypothese überein, dass Thiole innerhalb von biologischen Membranen als radikalische Kettentransferagentien wirken. Diese Eigenschaft wird in der Polymerchemie durch Nutzung von lipophilen Thiolen in hydrophoben Milieus technisch für die Produktion von Polymeren benutzt. Da die Thiylradikal-spezifische Reaktion von cis-Fettsäuren zu trans-Fettsäuren in 12SH behandelten Zellen verstärkt ablief, kann gefolgert werden, dass 12SH zellulär radikalisiert wurde. In lebenden Organismen kann demnach die Oxidation von Cystein die Schädigung von Membranen beschleunigen und damit Einfallstore für die laterale Radikalisierung von integralen Membranproteinen schaffen, welche möglicherweise der Langlebigkeit abträglich ist, zumindest, wenn sie in der inneren Mitochondrienmembran auftritt.

Swash-aquifer interaction in the vicinity of the water table exit point on a sandy beach

The coupling of sandy beach aquifers with the swash zone in the vicinity of the water table exit point is investigated through simultaneous measurements of the instantaneous shoreline (swash front) location, pore pressures and the water table exit point. The field observations reveal new insights into swash-aquifer coupling not previously gleaned from measurements of pore pressure only. In particular, for the case where the exit point is seaward of the observation point, the pore pressure response is correlated with the distance between the exit point and the shoreline in that when the distance is large the rate of pressure drop is fast and when the distance is small the rate decreases. The observations expose limitations in a simple model describing exit point dynamics which is based only on the force balance on a particle of water at the sand surface and neglects subsurface pressures. A new modified form of the model is shown to significantly improve the model-data comparison through a parameterization of the effects of capillarity into the aquifer storage coefficient. The model enables sufficiently accurate predictions of the exit point to determine when the swash uprush propagates over a saturated or a partially saturated sand surface, potentially an important factor in the morphological evolution of the beach face. Observations of the shoreward propagation of the swash-induced pore pressure waves ahead of the runup limit shows that the magnitude of the pressure fluctuation decays exponentially and that there is a linear increase in time lags, behavior similar to that of tidally induced water table waves. The location of the exit point and the intermittency of wave runup events is also shown to be significant in terms of the shore-normal energy distribution. Seaward of the mean exit point location, peak energies are small because of the saturated sand surface within the seepage face acting as a "rigid lid'' and limiting pressure fluctuations. Landward of the mean exit point the peak energies grow before decreasing landward of the maximum shoreline position.

The interaction between metabolic disease and ageing

Two of the greatest crises that civilisation faces in the 21st century are the predicted rapid increases in the ageing population and levels of metabolic disorders such as obesity and type 2 diabetes. A growing amount of evidence now supports the notion that energy balance is a key determinant not only in metabolism but also in the process of cellular ageing. Much of genetic evidence for a metabolic activity-driven ageing process has come from model organisms such as worms and flies where inactivation of the insulin receptor signalling cascade prolongs lifespan. At its most simplistic, this poses a conundrum for ageing in humans – can reduced insulin receptor signalling really promote lifespan and does this relate to insulin resistance seen in ageing? In higher animals, caloric restriction studies have confirmed a longer lifespan when daily calorie intake is reduced to 60% of normal energy requirement. This suggests that for humans, it is energy excess which is a likely driver of metabolic ageing. Interventions that interfere with the metabolic fate of nutrients offer a potentially important target for delaying biological ageing.

The effect of graded levels of exercise on energy intake and balance in free-living men, consuming their normal diet

Objective: To assess the effect of graded increases in exercised-induced energy expenditure (EE) on appetite, energy intake (EI), total daily EE and body weight in men living in their normal environment and consuming their usual diets. Design: Within-subject, repeated measures design. Six men (mean (s.d.) age 31.0 (5.0) y; weight 75.1 (15.96) kg; height 1.79 (0.10) m; body mass index (BMI) 23.3(2.4) kg/m2), were each studied three times during a 9 day protocol, corresponding to prescriptions of no exercise, (control) (Nex; 0 MJ/day), medium exercise level (Mex; ~1.6 MJ/day) and high exercise level (Hex; ~3.2 MJ/day). On days 1-2 subjects were given a medium fat (MF) maintenance diet (1.6 ´ resting metabolic rate (RMR)). Measurements: On days 3-9 subjects self-recorded dietary intake using a food diary and self-weighed intake. EE was assessed by continual heart rate monitoring, using the modified FLEX method. Subjects' HR (heart rate) was individually calibrated against submaximal VO2 during incremental exercise tests at the beginning and end of each 9 day study period. Respiratory exchange was measured by indirect calorimetry. Subjects completed hourly hunger ratings during waking hours to record subjective sensations of hunger and appetite. Body weight was measured daily. Results: EE amounted to 11.7, 12.9 and 16.8 MJ/day (F(2,10)=48.26; P<0.001 (s.e.d=0.55)) on the Nex, Mex and Hex treatments, respectively. The corresponding values for EI were 11.6, 11.8 and 11.8 MJ/day (F(2,10)=0.10; P=0.910 (s.e.d.=0.10)), respectively. There were no treatment effects on hunger, appetite or body weight, but there was evidence of weight loss on the Hex treatment. Conclusion: Increasing EE did not lead to compensation of EI over 7 days. However, total daily EE tended to decrease over time on the two exercise treatments. Lean men appear able to tolerate a considerable negative energy balance, induced by exercise, over 7 days without invoking compensatory increases in EI.

Free Energy Gap Dependence of the Electron-Transfer Rate from the Inverted to the Normal Region

numerical study of the free energy gap (FEG) dependence of the electron-transfer rate in polar solvents is presented. This study is based on the generalized multidimensional hybrid model, which not only includes the solvent polarization and the molecular vibration modes, but also the biphasic polar response of the solvent. The free energy gap dependence is found to be sensitive to several factors, including the solvent relaxation rate, the electronic coupling between the surfaces, the frequency of the high-frequency quantum vibrational mode, and the magnitude of the solvent reorganization energy. It is shown that in some cases solvent relaxation can play an important role even in the Marcus normal regime. The minimal hybrid model involves a large number of parameters, giving rise to a diverse non-Marcus FEG behavior which is often determined collectively by these parameters. The model gives the linear free energy gap dependence of the logarithmic rate over a substantial range of FEG, spanning from the normal to the inverted regime. However, even for favorable values of the relevant parameters, a linear free energy gap dependence of the rate could be obtained only over a range of 5000-6000 cm(-1) (compared to the experimentally observed range of 10000 cm(-1) reported by Benniston et al.). The present work suggests several extensions/generalizations of the hybrid model which might be necessary to fully understand the observed free energy gap dependence.

Studies on the Effect of High Energy Ball Milling On the Structural, Electrical and Magnetic Properties of Some Normal Spinets in the Ultrafine Regime

The present work is an attempt to understand the characteristics of high energy ball milling on the structural, electrical and magnetic properties of some normal spinets in the ultra fine regime, Magnetism and magnetic materials have been a fascinating subject for the mankind ever since the discovery of lodestone. Since then, man has been applying this principle of magnetism to build devices for various applications. Magnetism can be classified broadly into five categories. They are diamagnetic, paramagnetic, ferromagnetic antiferromagnetic and ferrimagnetic. Of these, ferro and ferri magnetic materials assume great commercial importance due to their unique properties like appropriate magnetic characteristics, high resistivity and low eddy current losses. The emergence of nanoscience and nanotechnology during the last decade had its impact in the field of magnetism and magnetic materials too. Now, it is common knowledge that materials synthesized in the nanoregime exhibit novel and superlative properties with respect to their coarser sized counterparts in the micron regime. These studies reveal that dielectric properties can be varied appreciably by high-energy ball milling in nanosized zinc ferrites produced by coprecipitation method. A semi conducting behaviour was observed in these materials with the Oxygen vacancies acting as the main charge carrier for conduction, which was produced at the time of coprecipitation and milling. Thus through this study, it was possible to successfully investigate the finite size effects on the structural, electrical and magnetic properties of normal spinels in the ultra fine regime

Bone mineral density at distal tibia using dual-energy X-ray absorptiometry in normal women and in patients with vertebral osteoporosis or primary hyperparathyroidism

To assess the effect of age and disease on mineral distribution at the distal third of the tibia, bone mineral content (BMC) and bone mineral density (BMD) were measured at lumbar spine (spine), femoral neck (neck), and diaphysis (Dia) and distal epiphysis (Epi) of the tibia in 89 healthy control women of different age groups (20-29, n = 12; 30-39, n = 11; 40-44, n = 12; 45-49, n = 12; 50-54, n = 12; 55-59, n = 10; 60-69, n = 11; 70-79, n = 9), in 25 women with untreated vertebral osteoporosis (VOP), and in 19 women with primary hyperparathyroidism (PHPT) using dual-energy x-ray absorptiometry (DXA; Hologic QDR 1000 and standard spine software). A soft tissue simulator was used to compensate for heterogeneity of soft tissue thickness around the leg. Tibia was scanned over a length of 130 mm from the ankle joint, fibula being excluded from analysis. For BMC and BMD, 10 sections 13 mm each were analyzed separately and then pooled to define the epiphysis (Epi 13-52 mm) and diaphysis area (Dia 91-130 mm). Precision after repositioning was 1.9 and 2.1% for Epi and Dia, respectively. In the control group, at any site there was no significant difference between age groups 20-29 and 30-39, which thus were pooled to define the peak bone mass (PBM).(ABSTRACT TRUNCATED AT 250 WORDS)

Accelerometry and Energy Expenditure in Obese Adults and Normal Weight Controls

Objective: To evaluate a new triaxial accelerometer device for prediction of energy expenditure, measured as VO2/kg, in obese adults and normal-weight controls during activities of daily life. Subjects and methods: Thirty-seven obese adults (Body Mass Index (BMI) 37±5.4) and seventeen controls (BMI 23±1.8) performed eight activities for 5 to 8 minutes while wearing a triaxial accelerometer on the right thigh. Simultaneously, VO2 and VCO2 were measured using a portable metabolic system. The relationship between accelerometer counts (AC) and VO2/kg was analysed using spline regression and linear mixed-effects models. Results: For all activities, VO2/kg was significantly lower in obese participants than in normalweight controls. A linear relationship between AC and VO2/kg existed only within accelerometer values from 0 to 300 counts/min, with an increase of 3.7 (95%-confidence interval (CI) 3.4 - 4.1) and 3.9 ml/min (95%-CI 3.4 - 4.3) per increase of 100 counts/min in obese and normal-weight adults, respectively. Linear modelling of the whole range yields wide prediction intervals for VO2/kg of ± 6.3 and ±7.3 ml/min in both groups. Conclusion: In obese and normal-weight adults, the use of AC for predicting energy expenditure, defined as VO2/kg, from a broad range of physical activities, characterized by varying intensities and types of muscle work, is limited.

Gamma-shaped long-cavity normal-dispersion mode-locked Er-fiber laser for sub-nanosecond high-energy pulsed generation

We propose the design of a novel ?-shaped fiber laser resonator and apply it to build a long-cavity normaldispersion mode-locked Er-fiber laser which features enhanced functionalities for management and optimization of pulsed lasing regimes. We report the generation of sub-nanosecond pulses with the energy of ~0.5 µJ at a kilohertz-scale repetition rate in an all-fiber system based on the new laser design. A combination of special design solutions in the laser, such as polarization instability compensation in the ultra-long arm of the resonator, intra-cavity spectral selection of radiation with a broadband fiber Bragg grating, and polarization selection by means of a tilted refractive index grating, ensures low amplified spontaneous emission (ASE) noise and high stability of the laser system output parameters.

Gamma-shaped long-cavity normal-dispersion mode-locked Er-fiber laser for sub-nanosecond high-energy pulsed generation

We propose the design of a novel ?-shaped fiber laser resonator and apply it to build a long-cavity normaldispersion mode-locked Er-fiber laser which features enhanced functionalities for management and optimization of pulsed lasing regimes. We report the generation of sub-nanosecond pulses with the energy of ~0.5 µJ at a kilohertz-scale repetition rate in an all-fiber system based on the new laser design. A combination of special design solutions in the laser, such as polarization instability compensation in the ultra-long arm of the resonator, intra-cavity spectral selection of radiation with a broadband fiber Bragg grating, and polarization selection by means of a tilted refractive index grating, ensures low amplified spontaneous emission (ASE) noise and high stability of the laser system output parameters.