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Background: Southeast Asian (SEA) mangroves are globally recognized as blue carbon hotspots. Methodologies that measure mangrove soil carbon stock (SCS) are either accurate but costly (i.e., elemental analyzers), or economical but less accurate (i.e., loss-on-ignition [LOI]). Most SEA countries estimate SCS by measuring soil organic matter (OM) through the LOI method then converting it into organic carbon (OC) using a conventional conversion equation (%Corg = 0.415 * % LOI + 2.89, R2 = 0.59, n = 78) developed from Palau mangroves. The local site conditions in Palau does not reflect the wide range of environmental settings and disturbances in the Philippines. Consequently, the conventional conversion equation possibly compounds the inaccuracies of converting OM to OC causing over- or under-estimated SCS. Here, we generated a localized OM-OC conversion equation and tested its accuracy in computing SCS against the conventional equation. The localized equation was generated by plotting % OC (from elemental analyzer) against the % OM (from LOI). The study was conducted in different mangrove stands (natural, restored, and mangrove-recolonized fishponds) in Oriental Mindoro and Sorsogon, Philippines from the West and North Philippine Sea biogeographic regions, respectively. The OM:OC ratios were also statistically tested based on (a) stand types, (b) among natural stands, and (c) across different ages of the restored and recolonized stands. Increasing the accuracy of OM-OC conversion equations will improve SCS estimates that will yield reasonable C emission reduction targets for the country's commitments on Nationally Determined Contributions (NDC) under the Paris Agreement. Results: The localized conversion equation is %OC = 0.36 * % LOI + 2.40 (R2 = 0.67; n = 458). The SOM:OC ratios showed significant differences based on stand types (x2 = 19.24; P = 6.63 × 10–05), among natural stands (F = 23.22; p = 1.17 × 10–08), and among ages of restored (F = 5.14; P = 0.03) and recolonized stands (F = 3.4; P = 0.02). SCS estimates using the localized (5%) and stand-specific equations (7%) were similar with the values derived from an elemental analyzer. In contrast, the conventional equation overestimates SCS by 20%. Conclusions: The calculated SCS improves as the conversion equation becomes more reflective of localized site conditions. Both localized and stand-specific conversion equations yielded more accurate SCS compared to the conventional equation. While our study explored only two out of the six marine biogeographic regions in the Philippines, we proved that having a localized conversion equation leads to improved SCS measurements. Using our proposed equations will make more realistic SCS targets (and therefore GHG reductions) in designing mangrove restoration programs to achieve the country's NDC commitments. [ABSTRACT FROM AUTHOR]

The aim of this study was to produce an alcohol gel hand sanitizer containing green glycerol. Crude glycerol was purified using chemical and physical treatments. The sanitizer was prepared using 71.100 g of 99.3° GL ethanol, 28.0 g H2O, 0.5 g of Carboxypolymethylene [Carbopol 940® or Carbomer], 5 drops of triethanolamine (pH 5–7), and glycerol (1.5% w/w). The thermal behavior of the ethanol, carbopol, triethanolamine, glycerol, and alcohol gels were evaluated using Thermogravimetry and Differential Thermal Analysis. The apparent viscosity was obtained using a rotary viscometer. The determination of in vitro spreadability was achieved by an adaptation of the Knorst method. The ethanol content was measured by headspace gas chromatography using a flame ionization detector. The thermal behavior of the gels was influenced by the presence of glycerol, which confirms the possible network interactions formed. The relative densities of the samples were between 0.887 and 0.890 g/cm3. No alteration of the pH of the formulation resulted from the incorporation of glycerol. The apparent viscosities of the alcohol gels were greater than 20,000 cP. No alteration in the in vitro spreadability of the gel alcohol (530.6 mm2) resulted from the addition of glycerol. Hand sanitizer was produced using glycerol from a transesterification reaction. It represents an alternative use for the glycerol being produced in biodiesel processes. The product satisfied the requirements of WHO that preconize a formulation containing 1.45% glycerol as an humectant to protect skin against dryness and dermatitis. [ABSTRACT FROM AUTHOR]

We present an experimental study aiming at the identification of the hydraulic conductivity in an aquifer which was packed according to four different configurations. The conductivity was estimated by means of slug tests, whereas the other parameters were determined by the grain size analysis. Prior to the fractal we considered the dependence of the conductivity upon the porosity through a power (scaling) law which was found in a very good agreement within the range from the laboratory to the meso-scale. The dependence of the conductivity through the porosity was investigated by identifying the proper fractal model. Results obtained provide valuable indications about the behavior, among the others, of the tortuosity, a parameter playing a crucial role in the dispersion phenomena taking place in the aquifers. [ABSTRACT FROM AUTHOR]

We deal with the spatial distribution of the hydraulic conductivity K within heterogeneous porous formations where a radial flow (typical of pumping and slug tests) is taking place. In particular, the study provides a wide data-set which is instrumental to corroborate theoretical findings about the stochastic behavior of K in the above flow configuration. Here, K-data pertain to a series of slug tests conducted within a large caisson which was densely instrumented in order to capture the transitional behavior of the conductivity from the near field (close to the pumping well) to the far field (away from the pumping well). For the experiments at stake, it is shown that the apparent conductivity K app is a very robust property. In fact, with the exception of a very tiny annulus surrounding the pumping well, K app can be used to solve flow (and transport) problems in close analogy to the effective theory approach adopted for a groundwater-type flow. It is hoped that the data-set exploited in the present study will be useful for other researchers who are engaged with similar studies. [ABSTRACT FROM AUTHOR]

Purpose: Despite occupying only 0.5% of the global coastal ocean, mangroves play a disproportionately large role in the capture and retention of atmospheric carbon dioxide as organic carbon (OC) in its sediments. However, the capacity of mangrove sediments to store high amounts of OC has never been explained mechanistically. This study elucidates the role of reactive iron (FeR) in long-term carbon sequestration in mangrove sediments.Materials and methods: Sediment samples of up to 1 m in depth were collected from six selected mangrove areas across the Philippines. The samples were characterized using X-ray diffraction (XRD) and X-ray fluorescence (XRF). A citrate-bicarbonate-dithionite reduction procedure was employed to extract FeR from the sediments. The OC concentration and δ13C signatures before and after FeR extraction were determined using a dichromate oxidation technique and isotope ratio mass spectrometry (IRMS), respectively.Results and discussion: XRD diffractograms showed that the mangrove sediment samples varied in terms of mineralogical characteristics, which reflected their different parent materials. It was found that the OC concentration increased exponentially (OC = 8.38e0.37FeR; R2 = 0.88; p < 0.0001) with increasing FeR concentration. δ13C signatures of FeR-associated OC revealed that FeR preferentially preserved terrestrial over marine-derived organic matter. Finally, FeR was estimated to coprecipitate with up to 5.44 × 1012 g OC in mangrove sediments per year.Conclusions: The findings of this study suggest that FeR is responsible for the preservation of OC, thus making mangrove sediments a "giant rusty sponge" for carbon. This mechanistic understanding of the long-term carbon storage in mangrove sediments could help draft better strategies for blue carbon initiatives that include the mangrove ecosystems. [ABSTRACT FROM AUTHOR]

There are three major issues in modeling solar evanescent oscillations: the variation of the intensity [ I]-velocity [ V] phase difference of p-modes close to the base of photosphere; the existence of a plateau of negative I- V phase differences below and between the ridges of the low-frequency p-modes; the explanation of the I- V cross-spectra of the evanescent oscillations. We present new interpretations for the first two issues, based on modeling intensity fluctuations taking steep temperature gradients, opacity, and non-adiabatic cooling into account. We also discuss consequences of our model for the explanation of power spectra and cross-power spectra of p-modes. In particular, we present evidence that the acoustic sources that generate evanescent waves produce a coherent background that explains the plateau-interridge regime of negative I- V phase difference. [ABSTRACT FROM AUTHOR]

The machining process for vertical turning martensitic gray cast iron is of great importance to the automotive industry, mainly in the manufacturing process of piston rings. The aim of this paper is to demonstrate the process of development of coated carbide tools to maximize the productivity of the process, considering the maximum life of the cutting tool and the minimum machining cost per part. Using full-factorial design of experiments, we tested two different geometries: a square tool with special geometry-formed by two edges and two ends simultaneously cutting-and a hexagonal tool. Considering that the special square geometry provided maximum life, full quadratic models for responses of interest were constructed using a central composite design for feed ( f) and rotation ( n). Applying the generalized reduced gradient algorithm, the proposed optimization goals were achieved with feed f = 0.37 mm/v and rotation of 264 rpm for the use of the special square tool. Confirmation experiments prove the effectiveness of this solution. [ABSTRACT FROM AUTHOR]

VAMOS is a Magneto-Optical Filter (MOF) that can acquire nearly simultaneous Dopplergrams and magnetograms with high cadence in the K I 7699 Å line. We performed an accurate set-up of this instrument in view of its use for studying oscillations in solar magnetic regions. The optimal set-up for VAMOS was achieved and an extra result of the spectral transmission measurements was found. The MOF and Wing Selector (WS) bandpasses depend not only on the cell temperature and magnetic field but also on the radiation intensity entering the cell, when this radiation exceeds a suitable level. We call this effect The Intensity Effect. [ABSTRACT FROM AUTHOR]

Fitting observed power and cross spectra of medium-degree p modes in velocity ( V) and intensity ( I) has been widely used for getting information about the p-mode excitation process and, in particular, for trying to determine the type and location of the acoustic sources. Numerical simulations of solar convection allow one to “observe” velocity and temperature ( T, used as proxy for I) fluctuations in different reference frames. Sampling the oscillations on planes of constant optical depth ( τ-frame) closely corresponds to the observer’s point of view, whereas sampling the oscillations at constant geometrical height ( z-frame) is more appropriate for comparison with predictions from theoretical models based on Eulerian hydrodynamics. The results of the analysis in the two frames show significant differences. Considering the effects introduced on oscillations by the steep temperature gradient of the photosphere and by the temperature- and pressure-dependent continuum opacity, we develop a new model for fitting the simulated V and T power and cross spectra both in the τ- and z-frames and discuss its merits and limitations. [ABSTRACT FROM AUTHOR]

We present new results about the phase difference between the intensity and velocity fluctuations of the solar photosphere obtained with the Velocity And Magnetic Observations of the Sun (VAMOS) instrument, which uses the magneto-optical filter (MOF) technique. Before this observing run, we applied the calibration method described in Magrì, Oliviero, and Severino ( Solar Phys. 232, 159, ) to reduce the instrumental cross-talk which was present in previous VAMOS data. The quality of this calibration, which can be easily applied to any MOF-based instrument, has been confirmed by comparing with the MOF transmission-profile measurements obtained with a diode laser system. Finally, we discuss the new VAMOS phase-difference value in relation to data obtained by other authors in the same potassium spectral line and in other lines that can be used to study nonadiabatic effects of solar global oscillations. [ABSTRACT FROM AUTHOR]

The intensity and velocity fluctuations, observed simultaneously, are a powerful diagnostic tool of the dynamics of the solar atmosphere. The phase relation between the fluctuations can improve our knowledge of the solar background, its relation with the acoustic sources, and its interaction with the solar acoustic oscillations. Furthermore, the opposite asymmetries observed along the p-mode line profiles in the intensity and velocity power spectra contain information about the source of the solar acoustic oscillations. For these reasons, it is relevant to study the height dependence of the asymmetries and phases in the solar atmosphere. In this paper, we present the results from the analysis of observations performed by the VAMOS instrument in the potassium 769.9 nm line and Na i D lines, and compare the measured phases with those obtained at different layers in the solar atmosphere by different instruments, spanning from the base of the photosphere to the low chromosphere. [ABSTRACT FROM AUTHOR]

Saturated flow takes place in geological formations of spatially variable permeability which is regarded as a stationary random space function of given statistical moments. The flow is assumed to be uniform in the mean and the Eulerian velocity field has stationary fluctuations. Water carries solutes that react according to the nonlinear equilibrium Freundlich isotherm. Neglecting pore scale dispersion (high Peclet number), we study the behavior of an initially finite pulse injection of constant concentration. Mean flux-averaged concentration is derived in a simple manner by using the previously determined solution of transport in a homogeneous one-dimensional medium and the Lagrangian methodology developed by Cvetkovic and Dagan [5] to model reactive transport in a three-dimensional flow field. The mean breakthrough curves are computed and the combined effect of reactive parameters and heterogeneity upon reduction of the concentration peak is investigated. Furthermore, with the aid of temporal moments, we determine equivalent reaction and macrodispersion coefficients pertinent to a homogeneous medium. [ABSTRACT FROM AUTHOR]

We study the center-limb (CL) variation of the average profiles of four Ca i lines near λ6500 and compare these observations with synthetic data obtained from several line formation models having different thermal structures, line parameters, LTE and non-LTE conditions, and micro and macroturbulence values, to assess the formation characteristics of our Ca i lines in the solar photosphere. Comparison of numerical results with observations indicates that non-LTE is indispensable to fit the CL variation of the central residual intensity for the line λ6493, and anisotropic microturbulence is indispensable to improve the CL behavior of the equivalent widths for all lines. The Ca i line analysis favors a cool photospheric model, but this cannot be disentangled clearly from the effects of non-LTE and small-scale velocity fields on the grounds of the present line formation models. [ABSTRACT FROM AUTHOR]

We use the 6-8-12 interatomic potential, with a suitable scaling for the relevant atomic radii, to reproduce the measured broadening and shift of the alkali resonance lines perturbed by noble gases, at temperatures of ∼ 500 K. Then, using the fit to the data with helium and neon as perturbers, we compute new values for the broadening and shift of the alkali resonance lines due to atomic hydrogen, at the temperature of 5000 K, which are of interest in the analysis of solar and stellar spectra, and discuss the reliability of these results. [ABSTRACT FROM AUTHOR]

The broadening and shift parameters for a number of Fe i lines perturbed by atomic hydrogen are computed using the interatomic potential due to Hindmarsh et al. (1967, 1970). It is also shown that the rms radius and the effective radius of the radiating atom, which determine the force constants in the interatomic potential, can be simply related each other, depending on the orbital quantum number of the atomic level. [ABSTRACT FROM AUTHOR]

We study the effects of both the solar granulation and short-period oscillations on the solar profile of the Ki 7699 resonance line and its center-to-limb variations. The granular model we used is that of Nelson (1978). The wave field is obtained by adding two 30 s acoustic waves with opposite horizontal wavenumbers to allow for the center-to-limb calculations. We find that the broadening and strengthening produced by our dynamical models do not fill the gap existing between the observations and the values computed in a static atmosphere. Then, either the granular model has to be revised (in particular its r.m.s. velocities are too low) or other types of motions, like gravity waves, have to be accounted for. The upper part of the mean bisectors is affected by granulation and the lower part by waves. With some qualification concerning the data used for comparison, a satisfactory fit of the observed center-to-limb variations of the mean bisectors is obtained when both dynamical models are included and the granular velocities are increased by a factor 1.5. [ABSTRACT FROM AUTHOR]

We examine the effects of acoustic-gravity waves with long and short periods on the solar profile of the K i7699 line using a dynamic model of line formation. First we studied the kinetic equilibrium of the K i atoms in a static atmosphere confirming, with up-to-date atomic data and atmospheric model, that a good fit of the resonance line 7699 is possible only when non-LTE effects are accounted for. Then the static non-LTE line source function and lower-level population are used as input data for calculating the line formation in the presence of waves. The time behaviour of the synthetic profiles corresponding to 300 s and 30 s waves is extensively discussed. The characteristic redshift induced by the 30 s wave is explained within the framework of the S-S line formation model. Long-period waves yield an anticorrelation between the asymmetry at different residual intensities and the line core shift, as observed. The short-period waves with velocity amplitude of about 100 m s (at the base of the photosphere) produce a mean bisector whose lower part has a slope in agreement with the observed one. The efficiency of waves to produce macro and microturbulence is also discussed. [ABSTRACT FROM AUTHOR]

A letter to the editor concerning a study on diacylglycerol kinase eta and bipolar disorder is presented.

In the last years we have gained some experience in the diagnostics of small-scale structures, both on the interpretative and on the observational point of view. We report here the conclusions and the suggestions for future developments attained in two main fields of interest. [ABSTRACT FROM AUTHOR]

The person-to-person variability of drug response is a major problem in clinical practice and in drug development. It can lead to therapeutic failure or adverse drug reactions (ADRs) in individuals or subpopulation of patients. In addition to the high occurrence of ADRs and the associated morbidity and mortality, substantial costs are incurred. Potential risk factors for drug inefficacy or toxicity include drug-drug interactions, the patient's age, renal and liver functions or other disease factors, and lifestyle variables such as smoking and alcohol consumption. In addition, it has become clear in recent years that genetic factors may also significantly modify drug responses or increase the risk for ADRs. Genetic variations in genes (polymorphisms) for drug-metabolizing enzymes, drug receptors, and drug transporters have been associated with individual variability in the efficacy and toxicity of drugs. It is now widely accepted that migraine is a polygenic and multifactorial disorders, thus considered to be a genetic complex disease. Genetic studies on migraine suggested a role of CACNA1A and DRD2 genes as susceptibility genes in this disorder. [ABSTRACT FROM AUTHOR]