bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effect of Chloride Ions on the Passive Films of Titanium in Sulfuric Acids
Authors: Liu Jing , Alfantazi Akram , Asselin Edouard
Published: January 2015

The effect of chloride ions on the passivity of titanium in sulfuric acids was investigated by potentiodynamic and potentiostatic anodizing, Mott-Schottky analysis and the point defect model (PDM). The anodizing results indicated that chloride ions facilitate the anodic passivity of titanium in sulfuric acids. Based on the Mott-Schottky analysis in conjunction with the PDM, it was shown that the donor density decreases exponentially with increasing film formation potential. Also, the results indicated that with the increasing concentration of chloride ions, the donor density decreases, while the diffusivity of the donors increases at the same film formation potential.
Corrosion Fatigue Crack Propagation Rates for Steam Turbine Blade 13% Cr Steels
Authors: Bashir Alyona , Dudziński Włodzimierz , Dudziński Marek , Ptak Teresa
Published: January 2015

Studies of stress corrosion in X12Cr13 and X20Cr13 steels used for rotor blades of steam turbines have been conducted for determining the average rate of corrosion cracking development da / dt. Specimens were exposed to the salt mist environment of 1,2 ppm NaCl concentration in temperature of 60° C. The research environment represents the initial condensate of humidity from 3÷4%. Average rate of corrosion cracking development for specimens of the X12Cr13 is by 0,005 µm/h higher from specimens of the X20Cr13 steel. Course of the corrosion cracking initiation depends to a high degree on metal structure, and probably the close value of cracking propagation rate depends on the similar structure of those steels – high-tempered martensite with carbides at grain boundaries.
The Electrochemical and Immersion Corrosion of Casting Magnesium Alloys Containing Rare Earth Elements
Authors: Kiełbus Andrzej , Michalska Joanna , Dybowski Bartłomiej
Published: January 2015

Magnesium alloys are widely used mainly in automotive and aerospace industries. There is quite a lot of information about corrosion of the magnesium alloys in available literature. However, the publications concern mainly Mg-Al alloys, while there is a lack of information about Mg-RE-Zr alloys. The following paper presents results of the investigations on the electrochemical corrosion of magnesium casting alloys containing rare earth elements (WE43, WE54, EV31A-Elektron 21) as well as pure magnesium. The alloys were investigated by immersion test in 3.5% NaCl for times up to 7 days. Electrochemical investigations were carried out at ambient temperature in aerated NaCl solution, using potentiodynamic polarization method. It has been shown that the best corrosion resistance is exhibited by alloys with yttrium addition (WE43, WE54), while the weakest by pure magnesium. EV31A alloy exhibits the highest corrosion rate during the immersion test, while WE54 and WE43 alloys had a similar corrosion behavior.
Electrochemical Corrosion Behaviour of Stainless Steels AISI 304 and 316L in Caribbean Sea Water
Authors: Herrera-Zamora D.M. , Veleva Lucien , López Juan Luis
Published: January 2015

AISI 304 and 316L flat samples were exposed during 3 months in Carribean sea water.At the end of the experiment Ecorr of AISI 316L reached one-half the negative potential value than that of AISI 304. The tendencies of Ecorr were correlated with the pitting corrosion development. They could be considered as a consequence of the opposition between the nucleation of new pits and repassivation of active sites. The analysis of Ecorr fluctuations was carried out with the potential spectral density (PSD) vs. frequency in logarithmic scale. The decrease of the PSD slopes, exponent b values, indicated a release of spontaneous energy with the advance of pits formation on the stainless steel surface. The data showed that in the range of low frequencies the process that occurs on both stainless steels surfaces could be considered as fractional Brownian motion, an anti-persistent non-stationary process, while in the range of higher frequencies as fractional Gaussian noise, an persistent stationary.
Adsorption Kinetics of Benzothiazole and 2-Mercaptobenzothiazole on Microcrystalline Gold and Silver Surfaces
Authors: Ramírez Cano Jorge , Veleva Lucien
Published: January 2015

Adsorption kinetics of benzothiazole (BNS) and mercaptobenzothiazole (2-MBT) (1×10-1M, 1×10-2M and 1×10-3M) were studied during 5000 s on gold and silver coated At-cut quartz microelectrodes, using EQCM. The frequency change fits well to the Langmuir isotherm in the case of 2-MBT, while BNS presents adsorption-desorption periods making the fitting non realiable. The calculated ΔGads of 2-MBT corresponds to physisorption Ag (-1.38 kcal mol-1) and Au (-1.94 kcal mol-1). On both metal surfaces (Au and Ag) the amount of adsorbed mass for 2-MBT is significantly larger (20.76 μg cm-2 and 6.03 μg cm-2) than on BNS (0.33 μg cm-2 and 0.88 μg cm-2). These facts could be explained by the deprotonation of 2-MBT giving place to an anion, which is prone to interact with both positively charged surfaces of Au and Ag. However, BNS protonates giving place to a cation and making more difficult its adsorption on both metals.
Refining a socio-economic status scale for use in community-based health research in India
Authors: Dudeja P , Bahuguna P , Singh A , Bhatnagar N
Published: January 2015

Objective:

Socio economic status is an important determinant of health and disease in population. Various scales for measuring the same exist in modern Indian society each with it's own limitations. Present study was done to abridge the existing and latest available Aggarwal Scale. Study Design: Cross Sectional Study

Material and methods:

All relevant information pertaining to Aggarwal et al scale was collected for 197 households and analyzed in SPSS 16. Data reduction was done using Factor Analysis (FA) under which Principal Components Analysis (PCA) was used.

Results:

Four components were selected based on criteria Eigen value of more than one and elbowing in scree plot. All the 22 items of Aggarwal et al were divided among these 4 components. Based on factor loadings four reduced scales were constructed. Percentage agreement of reduced scales with original scale increased as we increased the number of items in the scale. Analysis narrowed down the 22 items of Aggarwal et al scale to six items e.g. locality, education of husband/ wife, occupation of husband/ wife, family possessions, caste and monthly per capita income. These 6 items together accounted for 49% of the variation and can be taken as a surrogate measure of SES of the family.

Conclusion:

We have presented reduced versions of Aggarwal et al scale along with degree of agreement with the original scale. Authors propose the use of these scales to measure SES to overcome the time constraint in practicing research.
An audit of histopathology reports of carcinoma endometrium
Authors: Deodhar KK , Rekhi B , Menon S , Ganesh B
Published: January 2015

Background:

The aim was to see, compliance to minimum data information in carcinoma endometrium reports, in a team of 13 pathologists, and also to analyze these parameters e.g. tumor size, type, grade, depth of myometrial invasion, lymph node yield, pTNM stage etc.

Materials and Methods:

During the period of 2008-2010, from the files of Pathology department of our hospital, reports of 114 cases of carcinoma endometrium, who were operated in house, were analyzed.

Results:

The median age was 58.04 years and median tumor size was 4 cm. Endometrioid adenocarcinoma was the most common type (82.5%), followed by malignant mixed Mullerian tumor (MMMT) (6.1%) and Serous carcinoma (3.5%). Grade 2 was the commonest tumor grade (42.1%). Less than half of myometrial invasion was seen in 50% of the cases and more than half of the myometrial invasion was seen in 46.5% of cases. (Information was not available in four cases). Parametrial involvement was seen in 5.3% cases. The pTNM stage was not mentioned in 71.9% reports. The median lymph node yield was 15.

Conclusion:

The compliance to adhere to and to provide minimum data information in carcinoma endometrium reports is generally good. Lymph node yield is reasonable. Mentioning of pTNM staging is to be done more meticulously. Use of proformas/checklists is recommended.
In Vivo Quantification of Cerebral R2*-Response to Graded Hyperoxia at 3 Tesla
Authors: Gotzamanis Grigorios , Kocian Roman , Özbay Pinar S. , Redle Manuel , Kollias Spyridon , Eberhardt Christian , Boss Andreas , Nanz Daniel , Rossi Cristina
Published: January 2015

Objectives:

This study aims to quantify the response of the transverse relaxation rate of the magnetic resonance (MR) signal of the cerebral tissue in healthy volunteers to the administration of air with step-wise increasing percentage of oxygen.

Materials and Methods:

The transverse relaxation rate (R2*) of the MR signal was quantified in seven volunteers under respiratory intake of normobaric gas mixtures containing 21, 50, 75, and 100% oxygen, respectively. End-tidal breath composition, arterial blood saturation (SaO2), and heart pulse rate were monitored during the challenge. R2* maps were computed from multi-echo, gradient-echo magnetic resonance imaging (MRI) data, acquired at 3.0T. The average values in the segmented white matter (WM) and gray matter (GM) were tested by the analysis of variance (ANOVA), with Bonferroni post-hoc correction. The GM R2*-reactivity to hyperoxia was modeled using the Hill's equation.

Results:

Graded hyperoxia resulted in a progressive and significant (P < 0.05) decrease of the R2* in GM. Under normoxia the GM-R2* was 17.2 ± 1.1 s-1. At 75% O2 supply, the R2* had reached a saturation level, with 16.4 ± 0.7 s-1 (P = 0.02), without a significant further decrease for 100% O2. The R2*-response of GM correlated positively with CO2 partial pressure (R = 0.69 ± 0.19) and negatively with SaO2 (R = -0.74 ± 0.17). The WM showed a similar progressive, but non-significant, decrease in the relaxation rates, with an increase in oxygen intake (P = 0.055). The Hill's model predicted a maximum R2* response of the GM, of 3.5%, with half the maximum at 68% oxygen concentration.

Conclusions:

The GM-R2* responds to hyperoxia in a concentration-dependent manner, suggesting that monitoring and modeling of the R2*-response may provide new oxygenation biomarkers for tumor therapy or assessment of cerebrovascular reactivity in patients.
Role of Imaging and Cytogenetics in Evaluation of DiGeorge Syndrome - A Rare Entity in Clinical Practice
Authors: Ramachandran Rajoo , Babu Sellappan Rajamanickam , Ilanchezhian Subramanian , Radhakrishnan Prabhu Radhan
Published: January 2015

DiGeorge syndrome is a congenital genetic disorder that affects the endocrine system, mainly the thymus and parathyroid glands. The syndrome produces different symptoms, which vary in severity and character between patients. It manifests with craniofacial dysmorphism and defects in the heart, parathyroid, and thymus. Patients can present with a palatal deformity and nasal speech. This rare entity is caused mainly due to deletion of chromosome 22q11.2. Radiographic evaluation of DiGeorge syndrome is necessary to define aberrant anatomy, evaluate central nervous system, craniofacial abnormalities, musculoskeletal system, and cardiothoracic contents. It also helps in planning surgical procedures and surgical reconstructions. We report a case of DiGeorge syndrome in a 4-month-old neonate and discuss the clinical, imaging, and cytogenetic findings that helped in the diagnosis of this rare entity.
Bilateral Renal Lymphangiectasia: Radiological Findings by Ultrasound, Computed Tomography, and Magnetic Resonance Imaging
Authors: Elbanna Khaled Youssef , Almutairi Badr M. , Zidan Ahmed Touni
Published: January 2015

Renal lymphangiectasia is a rare benign condition of the kidney without specific clinical presentations. Classic imaging findings are described in literature. Here, we present a case of renal lymphangiectasia with history of bilateral flank pain and abnormal renal function tests. The radiological appearance on ultrasound (US) and computed tomography (CT) showed features of bilateral renal lymphangiectasia but the patient refused invasive procedure for aspiration of the cysts. So, follow-up of the patient was done by magnetic resonance imaging (MRI). Imaging findings of our case on US, CT, and MRI are discussed along with details of the additional finding of dilated retroperitoneal lymphatic channels, cisterna chyli, as well as the thoracic duct.
Unilateral Agenesis of Internal Carotid Artery with Intercavernous Anastomosis: A Rare Case Report
Authors: Kumaresh Athiyappan , Vasanthraj Praveen Kumar , Chandrasekharan Anupama
Published: January 2015

Unilateral agenesis of internal carotid artery (ICA) with intercavernous anastomosis is a rare congenital anomaly. We present a case of a 25-year-old female with 2-month history of holocranial headache. Neurological examination was unremarkable. Magnetic resonance imaging (MRI) with magnetic resonance angiography (MRA) showed absence of left ICA with an abnormal intercavernous vessel in the sella. Computed tomography (CT) showed absence of the left carotid canal. Doppler ultrasonography (USG) showed high resistance flow in the left common carotid artery (CCA). Since no hemorrhage or aneurysm was seen, patient was managed conservatively and is on regular follow-up. Based on our knowledge, this is the first case to demonstrate the features of unilateral agenesis of ICA with intercavernous anastomosis in X-ray, Doppler USG, CT, and MRI scans of the brain.
Inclusion of mountain-wave-induced cooling for the formation of PSCs over the Antarctic Peninsula in a chemistry–climate model
Authors: Orr A. , Hosking J. S. , Hoffmann L. , Keeble J. , Dean S. M. , Roscoe H. K. , Abraham N. L. , Vosper S. , Braesicke P.
Published: January 2015

Abstract. An important source of polar stratospheric clouds (PSCs), which play a crucial role in controlling polar stratospheric ozone depletion, is from the temperature fluctuations induced by mountain waves. However, this formation mechanism is usually missing in chemistry–climate models because these temperature fluctuations are neither resolved nor parameterised. Here, we investigate the representation of stratospheric mountain-wave-induced temperature fluctuations by the UK Met Office Unified Model (UM) at climate scale and mesoscale against Atmospheric Infrared Sounder satellite observations for three case studies over the Antarctic Peninsula. At a high horizontal resolution (4 km) the regional mesoscale configuration of the UM correctly simulates the magnitude, timing, and location of the measured temperature fluctuations. By comparison, at a low horizontal resolution (2.5° × 3.75°) the global climate configuration fails to resolve such disturbances. However, it is demonstrated that the temperature fluctuations computed by a mountain wave parameterisation scheme inserted into the climate configuration (which computes the temperature fluctuations due to unresolved mountain waves) are in relatively good agreement with the mesoscale configuration responses for two of the three case studies. The parameterisation was used to include the simulation of mountain-wave-induced PSCs in the global chemistry–climate configuration of the UM. A subsequent sensitivity study demonstrated that regional PSCs increased by up to 50% during July over the Antarctic Peninsula following the inclusion of the local mountain-wave-induced cooling phase.
A regional carbon data assimilation system and its preliminary evaluation in East Asia
Authors: Peng Z. , Zhang M. , Kou X. , Tian X. , Ma X.
Published: January 2015

Abstract. In order to optimize surface CO2 fluxes at grid scales, a regional surface CO2 flux inversion system (Carbon Flux Inversion system and Community Multi-scale Air Quality, CFI-CMAQ) has been developed by applying the ensemble Kalman filter (EnKF) to constrain the CO2 concentrations and applying the ensemble Kalman smoother (EnKS) to optimize the surface CO2 fluxes. The smoothing operator is associated with the atmospheric transport model to constitute a persistence dynamical model to forecast the surface CO2 flux scaling factors. In this implementation, the "signal-to-noise" problem can be avoided; plus, any useful observed information achieved by the current assimilation cycle can be transferred into the next assimilation cycle. Thus, the surface CO2 fluxes can be optimized as a whole at the grid scale in CFI-CMAQ. The performance of CFI-CMAQ was quantitatively evaluated through a set of Observing System Simulation Experiments (OSSEs) by assimilating CO2 retrievals from GOSAT (Greenhouse Gases Observing Satellite). The results showed that the CO2 concentration assimilation using EnKF could constrain the CO2 concentration effectively, illustrating that the simultaneous assimilation of CO2 concentrations can provide convincing CO2 initial analysis fields for CO2 flux inversion. In addition, the CO2 flux optimization using EnKS demonstrated that CFI-CMAQ could, in general, reproduce true fluxes at grid scales with acceptable bias. Two further sets of numerical experiments were conducted to investigate the sensitivities of the inflation factor of scaling factors and the smoother window. The results showed that the ability of CFI-CMAQ to optimize CO2 fluxes greatly relied on the choice of the inflation factor. However, the smoother window had a slight influence on the optimized results. CFI-CMAQ performed very well even with a short lag-window (e.g. 3 days).
Use of the CALIOP vertical feature mask for evaluating global aerosol models
Authors: Nowottnick E. P. , Colarco P. R. , Welton E. J. , da Silva A.
Published: January 2015

Abstract. Global aerosol distributions provided by the NASA Modern Era Retrospective Analysis for Research and Applications aerosol reanalysis (MERRAero) are evaluated using the aerosol types identified by the CALIOP vertical feature mask (VFM) algorithm, focusing especially on Saharan dust distributions during July 2009. MERRAero is comprised of an aerosol simulation produced in the Goddard Earth Observing System version 5 (GEOS-5) Earth system model and incorporates assimilation of MODIS-derived aerosol optical thickness to constrain column aerosol loadings. For comparison to the CALIOP VFM we construct two synthetic VFMs using the MERRAero aerosol distributions: a Level 2 VFM in which simulated MERRAero total attenuated backscatter and estimated particulate depolarization ratios are input directly to the CALIOP VFM typing algorithm, and a Level 3 VFM in which we map the aerosol species in MERRAero to the CALIOP VFM types. By comparing the simulated MERRAero-Level 2 VFM to CALIOP VFM we can diagnose the aerosol transport and speciation in MERRAero. By comparing the MERRAero-Level 2 and MERRAero-Level 3 simulated VFMs we perform a simple Observing System Simulation Experiment (OSSE), which is useful for identifying shortcomings in the CALIOP VFM algorithm itself. We find that despite having our column AOT constrained by MODIS, comparison to the CALIOP VFM reveals a greater occurrence of dusty aerosol layers in our MERRAero-Level 2 VFM, due to errors in MERRAero aerosol speciation. Additionally, we find that the CALIOP VFM algorithm classification for desert dust and polluted dust should be reconsidered for aerosol features that contain dust mixtures in low aerosol loadings, as our application of the CALIOP VFM to MERRAero distributions flagged a greater presence of dusty vs. marine aerosols when our two MERRAero VFMs were compared.
Traveling ionospheric disturbances triggered by the 2009 North Korean underground nuclear explosion
Authors: Zhang X. , Tang L.
Published: January 2015

Abstract. Underground nuclear explosions (UNEs) can induce acoustic-gravity waves, which disturb the ionosphere and initiate traveling ionospheric disturbances (TIDs). In this paper, we employ a multi-step and multi-order numerical difference method with dual-frequency GPS data to detect ionospheric disturbances triggered by the North Korean UNE on 25 May 2009. Several International GNSS Service (IGS) stations with different distances (400 to 1200 km) from the epicenter were chosen for the experiment. The results show that there are two types of disturbances in the ionospheric disturbance series: high-frequency TIDs with periods of approximately 1 to 2 min and low-frequency waves with period spectrums of 2 to 5 min. The observed TIDs are situated around the epicenter of the UNE, and show similar features, indicating the origin of the observed disturbances is the UNE event. According to the amplitudes, periods and average propagation velocities, the high-frequency and low-frequency TIDs can be attributed to the acoustic waves in the lower ionosphere and higher ionosphere, respectively.
Phosphorus release capacity of soluble P fertilizers and insoluble rock phosphate in response to phosphate solubilizing bacteria and poultry manure and their effect on plant growth promotion and P utilization efficiency of chilli (Capsicum annuum L.)
Authors: Abbasi M. K. , Musa N. , Manzoor M.
Published: January 2015

Abstract. The ability of soil microorganisms and organic manures to convert insoluble phosphorus (P) to an accessible form offers a biological rescue system for improving P solubilization and utilization in soil-plant systems. Our objective was to examine the P supplying capacity of soluble P fertilizers (SPF) i.e. single super phosphate (SSP) and di-ammonium phosphate (DAP) and insoluble rock phosphate (RP) after adding phosphate solubilizing bacteria (PSB) and poultry manure (PM) and their subsequent effect on the growth, yield and P-utilization efficiency (PUE) of chill (Capsicum annuum L.). An incubation study was carried-out on a sandy loam neutral soil with twelve treatments including T0: control; T1: RP; T2: SSP; T3: DAP; T4: PM; T5: 1/2 RP + 1/2 SSP; T6: 1/2 RP + 1/2 DAP; T7: 1/2 RP + 1/2 PM; T8: RP + PSB; T9: 1/2 RP + 1/2 SSP + PSB; T10: 1/2 RP + 1/2 DAP + PSB; T11: 1/2 RP + 1/2 PM + PSB. Phosphorus release capacity of added amendments was measured by analyzing extractable P from the amended soil incubated under controlled condition at 25 °C for 0, 5, 15, 25, 35, 60 days period. To complement the incubation study, a greenhouse experiment was conducted in pots with chilli (Capsicum annuum L.) used as a test crop. Growth, yield, P-uptake and PUE of the chilli was determined during the study. Results indicated that P release capacity of soil amended with RP varied between 6.0 and 11.5 mg kg-1 while the soluble P fertilizers i.e. SSP and DAP displayed a maximum of 73 and 68 mg P kg-1 at the start of the experiment (day 0). However, the P released tendency from SSP and DAP declined during incubation and at the end 82 and 79% of P initially present had been lost from the mineral pool. Integrated use of PSB and PM with RP in 1/2 RP + 1/2 PM + PSB treatment stimulated P mineralization by releasing a maximum of 25 mg P kg-1 that was maintained at high levels without any loss. Application of PSB tended to decrease pH showing an acidifying effect on soil. In the greenhouse experiment, RP alone or RP + PSB was not able to generate any significant impact on plant while DAP displayed the superiority over the remaining treatments. Combined use of RP, PM and PSB in 1/2 RP + 1/2 PM + PSB resulted in the growth, yield and P-uptake of chilli comparative/equivalent to that recorded under DAP. The PUE of applied P varied between 4–29% and higher in the treatments supplemented with PSB compared to those without PSB. These results suggest that use of PSB and PM with insoluble RP or with soluble P fertilizers could be a promising management strategy and viable technology to utilize both low-grade RP and SPF or PM efficiently for crop production and nutrient improvement in our cropping systems.
WETCHIMP-WSL: intercomparison of wetland methane emissions models over West Siberia
Authors: Bohn T. J. , Melton J. R. , Ito A. , Kleinen T. , Spahni R. , Stocker B. D. , Zhang B. , Zhu X. , Schroeder R. , Glagolev M. V. , Maksyutov S. , Brovkin V. , Chen G. , Denisov S. N. , Eliseev A. V. , Gallego-Sala A. , McDonald K. C. , Rawlins M. A. , Riley W. J. , Subin Z. M. , Tian H. , Zhuang Q. , Kaplan J. O.
Published: January 2015

Abstract. Wetlands are the world's largest natural source of methane, a powerful greenhouse gas. The strong sensitivity of methane emissions to environmental factors such as soil temperature and moisture has led to concerns about potential positive feedbacks to climate change. This risk is particularly relevant at high latitudes, which have experienced pronounced warming and where thawing permafrost could potentially liberate large amounts of labile carbon over the next 100 years. However, global models disagree as to the magnitude and spatial distribution of emissions, due to uncertainties in wetland area and emissions per unit area and a scarcity of in situ observations. Recent intensive field campaigns across the West Siberian Lowland (WSL) make this an ideal region over which to assess the performance of large-scale process-based wetland models in a high-latitude environment. Here we present the results of a follow-up to the Wetland and Wetland CH4 Intercomparison of Models Project (WETCHIMP), focused on the West Siberian Lowland (WETCHIMP-WSL). We assessed 21 models and 5 inversions over this domain in terms of total CH4 emissions, simulated wetland areas, and CH4 fluxes per unit wetland area and compared these results to an intensive in situ CH4 flux dataset, several wetland maps, and two satellite inundation products. We found that: (a) despite the large scatter of individual estimates, 12 year mean estimates of annual total emissions over the WSL from forward models (5.34 ± 0.54 Tg CH4 y-1), inversions (6.06 ± 1.22 Tg CH4 y-1), and in situ observations (3.91 ± 1.29 Tg CH4 y-1) largely agreed, (b) forward models using inundation products alone to estimate wetland areas suffered from severe biases in CH4 emissions, (c) the interannual timeseries of models that lacked either soil thermal physics appropriate to the high latitudes or realistic emissions from unsaturated peatlands tended to be dominated by a single environmental driver (inundation or air temperature), unlike those of inversions and more sophisticated forward models, (d) differences in biogeochemical schemes across models had relatively smaller influence over performance; and (e) multi-year or multi-decade observational records are crucial for evaluating models' responses to long-term climate change.
Understanding emissions of ammonia from buildings and application of fertilizers: an example from Poland
Authors: Werner M. , Ambelas Skjøth C. , Kryza M. , Dore A. J.
Published: January 2015

Abstract. A Europe-wide dynamic ammonia (NH3) emissions model has been applied for one of the large agricultural countries in Europe, and its sensitivity on the distribution of emissions among different agricultural functions was analysed by comparing with observed ammonia concentrations and by implementing all scenarios in a chemical transport model (CTM). The results suggest that the dynamic emission model is most sensitive to emission from animal manure, in particular how animal manure and its application on fields is connected to national regulations. In contrast, the model is most robust with respect to emission from buildings and storage. To incorporate the national regulations, we obtained activity information on agricultural operations at the sub-national level for Poland, information about infrastructure on storages, and current regulations on manure practice from Polish authorities. The information was implemented in the existing emission model and was connected directly with the NWP calculations from the Weather Research and Forecasting model (WRF-ARW). The model was used to calculate four emission scenarios with high spatial (5 km × 5 km) and temporal resolution (3 h) for the entire year 2010. In the four scenarios, we have compared the Europe-wide default model settings against (1) a scenario that focuses on emission from agricultural buildings, (2) the existing emission method used in WRF-Chem in Poland, and (3) a scenario that takes into account Polish infrastructure and agricultural regulations. The ammonia emission was implemented into the CTM FRAME and modelled ammonia concentrations was compared with measurements. The results suggest that the default setting in the dynamic model is an improvement compared to a non-dynamical emission profile. The results also show that further improvements can be obtained on the national scale by replacing the default information on manure practice with information that is connected with local practice and national regulations. Implementing a dynamical approach for simulation of ammonia emission is a viable objective for all CTM models that continue to use fixed emission profiles. Such models should handle ammonia emissions in a similar way to other climate-dependent emissions (e.g. biogenic volatile organic compounds). Our results, compared with previous results from the DEHM and the GEOS-CHEM models, suggest that implementing dynamical approaches improves simulations in general, even in areas with limited information about the location of the agricultural fields, livestock and agricultural production methods such as Poland.
The effects of past climate variability on fire and vegetation in the cerrãdo savanna ecosystem of the Huanchaca Mesetta, Noel Kempff Mercado National Park, NE Bolivia
Authors: Maezumi S. Y. , Power M. J. , Mayle F. E. , McLauchlan K. , Iriarte J.
Published: January 2015

Abstract. Cerrãdo savannas have the greatest fire activity of all major global land-cover types and play a significant role in the global carbon cycle. During the 21st century, temperatures are predicted to increase by ~ 3 °C coupled with a precipitation decrease of ~ 20%. Although these conditions could potentially intensify drought stress, it is unknown how that might alter vegetation composition and fire regimes. To assess how Neotropical savannas responded to past climate changes, a 14 500 year, high-resolution, sedimentary record from Huanchaca Mesetta, a palm swamp located in the cerrãdo savanna in northeastern Bolivia, was analyzed for phytoliths, stable isotopes and charcoal. A non-analogue, cold-adapted vegetation community dominated the Late Glacial-Early Holocene period (14 500–9000 ka), that included trees and C3 Pooideae and C4 Panicoideae grasses. The Late Glacial vegetation was fire sensitive and fire activity during this period was low, likely responding to fuel availability and limitation. Although similar vegetation characterized the Early Holocene, the warming conditions associated with the onset of the Holocene led to an initial increase in fire activity. Huanchaca Mesetta became increasingly fire-dependent during the Middle Holocene with the expansion of C4 fire adapted grasses. However, as warm, dry conditions, characterized by increased length and severity of the dry season, continued, fuel availability decreased. The establishment of the modern palm swamp vegetation occurred at 5000 cal yr BP. Edaphic factors are the first order control on vegetation on the rocky quartzite mesetta. Where soils are sufficiently thick, climate is the second order control of vegetation on the mesetta. The presence of the modern palm swamp is attributed to two factors: (1) increased precipitation that increased water table levels, and (2) decreased frequency and duration of surazos leading to increased temperature minima. Natural (soil, climate, fire) drivers rather than anthropogenic drivers control the vegetation and fire activity at Huanchaca Mesetta. Thus the cerrãdo savanna ecosystem of the Huanchaca Plateau has exhibited ecosystem resilience to major climatic changes in both temperature and precipitation since the Late Glacial period.
Scaling laws for perturbations in the ocean–atmosphere system following large CO2 emissions
Authors: Towles N. , Olson P. , Gnanadesikan A.
Published: January 2015

Abstract. Scaling relationships are derived for the perturbations to atmosphere and ocean variables from large transient CO2 emissions. Using the carbon cycle model LOSCAR (Zeebe et al., 2009; Zeebe, 2012b) we calculate perturbations to atmosphere temperature and total carbon, ocean temperature, total ocean carbon, pH, and alkalinity, marine sediment carbon, plus carbon-13 isotope anomalies in the ocean and atmosphere resulting from idealized CO2 emission events. The peak perturbations in the atmosphere and ocean variables are then fit to power law functions of the form γDαEbeta, where D is the event duration, E is its total carbon emission, and γ is a coefficient. Good power law fits are obtained for most system variables for E up to 50 000 PgC and D up to 100 kyr. However, these power laws deviate substantially from predictions based on simplified equilibrium considerations. For example, although all of the peak perturbations increase with emission rate E/D, we find no evidence of emission rate-only scaling α + β =0, a prediction of the long-term equilibrium between CO2 input by volcanism and CO2 removal by silicate weathering. Instead, our scaling yields α + β ≃ 1 for total ocean and atmosphere carbon and 0< α + β < 1 for most of the other system variables. The deviations in these scaling laws from equilibrium predictions are mainly due to the multitude and diversity of time scales that govern the exchange of carbon between marine sediments, the ocean, and the atmosphere.
S2P3-R (v1.0): a framework for efficient regional modelling of physical and biological structures and processes in shelf seas
Authors: Marsh R. , Hickman A. E. , Sharples J.
Published: January 2015

Abstract. An established 1-dimensional model of Shelf Sea Physics and Primary Production (S2P3) is adapted for regional use in realistic geographical domains over selected years, for selected regions. The S2P3-R framework (v1.0) can be used to efficiently map 3-D physical and biological structures in shelf seas, in particular the tidal mixing fronts that seasonally develop at boundaries between mixed and stratified water. The model has primarily been developed for undergraduate oceanography modules and research projects, providing a practical tool for linking theory and field observations, but it is also useful as an investigative research tool alongside more complex and computationally expensive models. Four different configurations of S2P3-R are described and evaluated, illustrating a range of diagnostics, evaluated where practical with available observations. The model can be forced with daily meteorological variables for any selected year in the reanalysis era (1948 onwards). Example simulations illustrate the considerable extent of synoptic-to-interannual variability in the physics and biology of shelf seas. In discussion, the present limitations of S2P3-R are emphasized, and future model developments are outlined.
An updated interparcel mixing algorithm in the Lagrangian advection scheme with shape matrix (LASM) v0.2
Authors: Dong L. , Wang B. , Liu L.
Published: January 2015

Abstract. The interparcel mixing algorithm in the Lagrangian advection scheme with shape matrix (LASM) is updated to make the scheme more robust. The linear degeneration criterion is replaced by the maximum deviation of the skeleton points so that the new algorithm is more effective in controlling the shape of parcels, which is vital for long time simulation. LASM is inherently shape-preserving without any complicated filter or limiter, so it is linear. This fact contributes to the ability of LASM of preserving the sum of multiple tracers exactly. A newly proposed terminator "toy"-chemistry test is also used to test LASM, which shows that LASM can preserve the weighted sum of two reactive chlorine-like species precisely.
Assessment of Halon-1301 as a groundwater age tracer
Authors: Beyer M. , van der Raaij R. , Morgenstern U. , Jackson B.
Published: January 2015

Abstract. Groundwater dating is an important tool to assess groundwater resources in regards to their dynamics, i.e. direction and time scale of groundwater flow and recharge, to assess contamination risks and manage remediation. To infer groundwater age information, a combination of different environmental tracers, such as tritium and SF6, are commonly used. However, ambiguous age interpretations are often faced, due to a limited set of available tracers and their individual restricted application ranges. For more robust groundwater dating multiple tracers need to be applied complementarily and it is vital that additional, groundwater age tracers are found to ensure robust groundwater dating in future. We recently suggested that Halon-1301, a water soluble and entirely anthropogenic gaseous substance, may be a promising candidate, but its behaviour in water and suitability as a groundwater age tracer had not yet been assessed in detail. In this study, we determine Halon-1301 and infer age information in 17 New Zealand groundwaters and various modern (river) water samples. The samples are simultaneously analysed for Halon-1301 and SF6, which allows identification of issues such as contamination of the water with modern air during sampling. Water at all analysed groundwater sites have also been previously dated with tritium, CFC-12, CFC-11 and SF6, and exhibit mean residence times ranging from modern (close to 0 years) to over 100 years. The investigated groundwater ranged from oxic to highly anoxic, and some showed evidence of CFC contamination or degradation. This allowed us to make a first attempt of assessing the conservativeness of Halon-1301 in water, in terms of presence of local sources and its sensitivity towards degradation etc., which could affect the suitability of Halon-1301 as groundwater age tracer. Overall we found Halon-1301 reliably inferred the mean residence time of groundwater recharged between 1980 and 2014. Where direct age comparison could be made 71% of mean age estimates for the studied groundwater sites were in agreement with ages inferred from tritium and SF6 (within ± 2 years). The remaining (anoxic) sites showed reduced concentrations of Halon-1301 along with even further reduced concentrations of CFCs. The reason(s) for this need to be further assessed, but are likely to be caused by sorption or degradation of the compounds. Despite some groundwater samples showing evidence of contamination from industrial or agricultural sources via elevated CFC concentrations, no sample indicated significantly elevated concentration of Halon-1301, which may indicate a lack of local anthropogenic or geologic sources of Halon-1301 contamination.
Flooding in river mouths: human caused or natural events? Five centuries of flooding events in the SW Netherlands, 1500–2000
Authors: de Kraker A. M. J.
Published: January 2015

Abstract. This paper looks into the flooding events of the past 500 years in the SW Netherlands addressing the issue what kind of flooding events have occurred and which ones have mainly natural causes and which ones are predominantly human induced. The flooding events are classified into two major categories: (a) flooding events that were caused during storm surges and (b) flooding events which happened during war fare. From both categories a selection of flooding events has been made. Each flooding event is discussed in terms time, location, extent of the flooded area and specific conditions. Among these conditions specific weather circumstances and how long they lasted, the highest water levels reached and dike maintenance are discussed as far as flooding events caused during storm surges are concerned. About the flooding events during war fare, offensive and defensive strategies are relevant. The paper demonstrates that although the strategic flooding events obviously were man-made, the natural feature, being the use of fresh water or sea water, of these events also played a major role. Flooding events caused during storm surge may have an obvious natural cause, but the extent of the flooding and damage it caused were largely determined by man.
Randomly distributed unit sources to enhance optimization in tsunami waveform inversion
Authors: Mulia I. E. , Asano T.
Published: January 2015

Abstract. In tsunami waveform inversion using the conventional Green's function technique, an optimal solution is sometimes difficult to obtain because of various factors. This study proposes a new method to both optimize the determination of the unknown parameters and introduce a global optimization method for tsunami waveform inversion. We utilize a genetic algorithm that further enhanced by a pattern search method to find an optimal distribution of unit source locations prior to the inversion. Unlike the conventional method that characterized by equidistant unit sources, our method generates a random spatial distribution of unit sources inside the inverse region. This leads to a better approximation of the initial profile of a tsunami. The method has been tested using an artificial tsunami source with real bathymetry data. Comparison results demonstrate that the proposed method has considerably outperformed the conventional one in terms of model accuracy.
Three-dimensional approach to understanding the relationship between the Plio-Quaternary stress field and tectonic inversion in the Triassic Cuyo Basin, Argentina
Authors: Giambiagi L. , Spagnotto S. , Moreiras S. M. , Gómez G. , Stahlschmidt E. , Mescua J.
Published: January 2015

Abstract. The Cacheuta sub-basin of the Triassic Cuyo Basin is an example of rift basin inversion contemporaneous to the advance of the Andean thrust front, during the Plio-Quaternary. This basin is one of the most important sedimentary basins in a much larger Triassic NNW-trending depositional system along the southwestern margin of the Pangea supercontinent. The amount and structural style of inversion is provided in this paper by three-dimensional insights into the relationship between inversion of rift-related structures and spatial variations in late Cenozoic stress fields. The Plio-Quaternary stress field exhibits important N–S variations in the foreland area of the Southern Central Andes, between 33 and 34° S, with a southward gradually change from pure compression with σ1 and σ2 being horizontal, to a strike-slip type stress field with σ2 being vertical. We present a 3-D approach for studying the tectonic inversion of the sub-basin master fault associated with strike-slip/reverse to strike-slip faulting stress regimes. We suggest that the inversion of Triassic extensional structures, striking NNW to WNW, occurred during the Plio–Pleistocene in those areas with strike-slip/reverse to strike-slip faulting stress regime, while in the reverse faulting stress regime domain, they remain fossilized. Our example demonstrates the impact of the stress regime on the reactivation pattern along the faults.
Remediation of degraded arable steppe soils in Moldova using vetch as green manure
Authors: Wiesmeier M. , Lungu M. , Hübner R. , Cerbari V.
Published: January 2015

Abstract. In the Republic of Moldova, non-sustainable arable farming led to severe degradation and erosion of fertile steppe soils (Chernozems). As a result, the Chernozems lost about 40% of their initial amounts of soil organic carbon (SOC). Aim of this study was to remediate degraded arable soils and promote carbon sequestration by implementation of cover cropping and green manuring in Moldova. Thereby, the suitability of the legume hairy vetch (Vicia sativa) as cover crop under the dry, continental climate of Moldova was examined. At two experimental sites, the effect of cover cropping on chemical and physical soil properties as well as on yields of subsequent main crops was determined. The results showed a significant increase of SOC after incorporation of hairy vetch due to a high above- and belowground biomass production that was related with a high input of carbon and nitrogen. A calculation of SOC stocks based on equivalent soil masses revealed a sequestration of around 3 t C ha-1 yr-1 as a result of hairy vetch cover cropping. The buildup of SOC was associated with an improvement of the soil structure as indicated by a distinct decrease of bulk density and a relative increase of macroaggregates at the expense of microaggregates and clods. As a result, yields of subsequent main crops increased by around 20%. Our results indicated that hairy vetch is a promising cover crop to remediate degraded steppe soils, control soil erosion and sequestrate substantial amounts of atmospheric C in arable soils of Moldova.
Dexamethasone Intravitreal Implant for Diabetic Macular Edema: Indications for a PRN Regimen of Treatment
Authors: Panozzo Giacomo , Gusson Elena , Panozzo Giorgio , Mura Giulia Dalla
Published: January 2015

Purpose

To define the mean time of first recurrence of diabetic macular edema (DME) after a single injection of dexamethasone intravitreal implant (DEX-I), reducing the burden of monthly visits during a PRN regimen of treatment.

Methods

Twenty phakic eyes with DME (12 eyes naïve and 8 eyes with edema persistent after previous treatments) were followed monthly after DEX-I injection until evidence of first recurrence of edema, defined as a change in visual acuity (VA) ≥5 letters and/or in foveal thickness (FT) ≥50 µm. Reaching this point, the eyes were re-treated. Monitored parameters were changes in VA, FT, intraocular pressure (IOP), and lens opacity.

Results

Maximal efficacy was registered at month 1, when mean VA improved by 14 letters (19%), FT decreased by 325 µm (43.7%), and in 15 eyes (75%) edema was completely reabsorbed. The mean time of first recurrence was 5.1 months. No statistical difference was found between eyes with naïve or persistent DME. Five eyes needed topical medication for modest temporary IOP increase (21-24 mm Hg) between months 2 and 4. No increase in lens opacities was registered during follow-up.

Conclusions

According to the results of this study, the first signs of DME recurrence after DEX-I injection appear at a mean time of 5 months, suggesting that an appropriate and prudent time schedule for a PRN regimen could be limited to monthly tonometry and a first complete examination not before 4 months.
Association of Neutrophil/Lymphocyte Ratio and Retinal Vein Occlusion
Authors: Dursun Ayhan , Ozturk Sultan , Yucel Hasan , Ozec Ayse Vural , Dursun Feyza Gulac , Toker Mustafa Ilker , Erdoğan Haydar , Arici Mustafa Kemal , Topalkara Aysen
Published: January 2015

Purpose

To evaluate the association between neutrophil/lymphocyte ratio (NLR) and the development of retinal vein occlusion (RVO).

Methods

Forty patients were included in the study. Forty age- and sex-matched healthy volunteers were recruited as the control group. The RVO diagnosis was made clinically, based on the findings of fundus examination. The NLR and file records of the patients and the control group were compared.

Results

The mean age of patients was 64 ± 12 years. Neutrophil levels were higher in RVO patients compared to the control subjects (5.1 ± 1.9 vs 3.6 ± 1.0, p<0.001). Lymphocyte levels were lower in RVO patients compared with the control subjects (2.0 ± 0.7 vs 2.6 ± 0.9, p = 0.005). The NLR was significantly higher in RVO patients compared with the control subjects (3.0 ± 2.7 vs 1.5 ± 0.3, p<0.001). According to the receiver operator characteristics curve analysis, the optimal cutoff value of NLR to predict RVO was >1.89, with 72.5% sensitivity and 100% specificity.

Conclusions

The current study demonstrated that higher NLR was associated with the development of RVO. The NLR may be used as a predictive tool for identifying risk for RVO.