bluuebunny/crossref_metadata_2025 huggingface dataset:
Historical fire regimes, reconstructed from land‐survey data, led to complexity and fluctuation in sagebrush landscapes
Authors: Bukowski Beth E. , Baker William L.
Published: October 2012

Sagebrush landscapes provide habitat for Sage‐Grouse and other sagebrush obligates, yet historical fire regimes and the structure of historical sagebrush landscapes are poorly known, hampering ecological restoration and management. To remedy this, General Land Office Survey (GLO) survey notes were used to reconstruct over two million hectares of historical vegetation for four sagebrush‐dominated (Artemisia spp.) study areas in the western United States. Reconstructed vegetation was analyzed for fire indicators used to identify historical fires and reconstruct historical fire regimes. Historical fire‐size distributions were inverse‐J shaped, and one fire >100 000 ha was identified. Historical fire rotations were estimated at 171–342 years for Wyoming big sagebrush (A. tridentata ssp. wyomingensis) and 137–217 years for mountain big sagebrush (A. tridentata ssp. vaseyana). Historical fire and patch sizes were significantly larger in Wyoming big sagebrush than mountain big sagebrush, and historical fire rotations were significantly longer in Wyoming big sagebrush than mountain big sagebrush. Historical fire rotations in Wyoming were longer than those in other study areas. Fine‐scale mosaics of burned and unburned area and larger unburned inclusions within fire perimeters were less common than in modern fires. Historical sagebrush landscapes were dominated by large, contiguous areas of sagebrush, though large grass‐dominated areas and finer‐scale mosaics of grass and sagebrush were also present in smaller amounts. Variation in sagebrush density was a common source of patchiness, and areas classified as “dense” made up 24.5% of total sagebrush area, compared to 16.3% for “scattered” sagebrush. Results suggest significant differences in historical and modern fire regimes. Modern fire rotations in Wyoming big sagebrush are shorter than historical fire rotations. Results also suggest that historical sagebrush landscapes would have fluctuated, because of infrequent episodes of large fires and long periods of recovery and maturity. Due to fragmentation of sagebrush landscapes, the large, contiguous expanses of sagebrush that dominated historically are most at risk and in need of conservation, including both dense and scattered sagebrush. Fire suppression in Wyoming big sagebrush may also be advisable, as modern fire rotations are shorter than their historical counterparts.
Temperature and Moisture Effects on Microbial Biomass and Soil Organic Matter Mineralization
Authors: Curtin Denis , Beare Michael H. , Hernandez-Ramirez Guillermo
Published: October 2012

Concern over climate change has stimulated interest in the temperature and moisture dependence of soil organic matter decomposition. In particular, there has been intense debate in relation to the factors that determine the temperature dependence of C mineralization. We examined temperature and moisture responses of C and N mineralization in an 85‐d laboratory incubation (factorial combination of four temperatures [5, 12, 18, 25°C] and five moisture treatments [matric potential from −5 to −1200 kPa]) using three agriculturally important New Zealand soils (soils with a history of pasture, arable, or vegetable cropping). Mineralization was linearly related to gravimetric moisture content, except in the high‐C pasture soil where O2 supply apparently limited mineralization at high (25°C) temperature–moisture combinations. Temperature responses were adequately described by a Q10 function (Q10 values for C mineralization ranged 1.9–2.8). The pool of mineralizable C, estimated using a first‐order kinetic model, increased as temperature and moisture increased, whereas the rate constant did not show a consistent trend with either temperature or moisture. Part of the C mineralized during the incubation was from the microbial biomass (post‐incubation biomass C decreased by an average of 0.22–0.31 mg kg−1 for each 1 mg kg−1 CO2–C evolved). Microbial biomass C (MBC) was particularly sensitive to temperature (post‐incubation biomass C decreased 18–35% between 5–25°C). The decline in MBC between 5 and 12°C represented an average of 40% of the C mineralization increase in that temperature interval. Between 18 and 25°C, the decline in MBC was equivalent to only 20% (on average) of the C mineralized in that temperature interval. High Q10 values reported in laboratory incubations at low temperature may be partly due to mineralization of microbial C.
Chemical Properties of Aluminum Tridecamer Transferred onto Chelating Resin
Authors: Etou Mayumi , Hagiwara Satoru , Saito Tomoyuki , Noma Hiroaki , Okaue Yoshihiro , Yokoyama Takushi
Published: October 2012

A transcription and concentration method of Al tridecamer (Al13) to Chelex 100 chelating ion exchange resin was developed to enhance the in situ detection sensitivity of the Al13 in an aqueous solution by 27Al magic angle spinning nuclear magnetic resonance. Based on this method, a new lower limit of Al concentration (at least 10−4 mol/L) required to form Al13 was discovered, which is the lowest detectable level known to date. It was found that once Al13 is transferred onto Chelex 100, which serves as a model compound of a soil surface covered with organic substances and microbes, its stability against pH is considerably enhanced (stable at pH 4–12).
Effects of ultrasonic pre-treatment on sludge characteristics and anaerobic digestion
Authors: Appels Lise , Houtmeyers Sofie , Van Mechelen Floriaan , Degrève Jan , Van Impe Jan , Dewil Raf
Published: October 2012

In this work, the influence of an ultrasonic pre-treatment on anaerobic digestion of waste activated sludge is studied. Attention is paid to the solubilisation of the main organic (proteins, carbohydrates) and inorganic (heavy metals) sludge components during ultrasonic treatment and the influence of the dry solids content (DS) on the degree of solubilisation. The second part of the paper focuses on the relationship between the applied specific energy of the ultrasonic treatment and methane production. In general, a higher specific energy and a higher DS content are beneficial for the release of organic matter, resulting in an increased methane production. The efficiency of the subsequent anaerobic digestion is similar for both sludge types (2.1 and 3.2% DS). However, at lower DS contents (2.1%), the methane production increase was more significant.
Evaluation of anaerobic biodegradability of wastewater from tebuconazole manufacturing
Authors: Silva M. C. A. , Monteggia L. O. , Leal F. K. , Delabary H. S.
Published: October 2012

This study aimed to verify the biological anaerobic treatability of tebuconazole effluent manufacturing. For this purpose, two preliminary batch tests were performed using an ‘anaerobic respirometer’ adjusting the initial pH of the effluent at 7.0 and 8.0, respectively (first phase). In addition, two tests (second phase) were run using sequential batch anaerobic fermenters, the first operated at different hydraulic detention times (10 and 16.7 days) and the second with different initial dilutions of the effluent (5 and 20%). The chemical oxygen demand (COD) removal observed on the anaerobic respirometer tests was in the range of 66–81%. According to the preliminary batch tests an optimal value of initial COD concentration and amount of biomass was identified, which was considered for the fermenters start up. However, it was observed that the optimal relation provided by the respirometer test was not a good parameter of operational control for the fermenters due to the accumulation of inhibitory substances, which affected the microbial activity and took the system to collapse. The initial dilution of the effluent (5 and 20%) was essential for the stability of the anaerobic system, allowing COD removals above 74% during this study.
Chitosan resins synthesised by improved drop-sphere-forming method for Cr(VI) removal from aqueous solutions
Authors: Li Shunyi , Wu Zhenjun , Li Bin , Zhu Rencheng , Wang Yan
Published: October 2012

An improved drop-sphere-forming (IDSF) method was applied to synthesise chitosan resin. Chitosan resin was synthesised by the self-made device and cross-linked with epichlorohydrin. The influences of concentration of chitosan–acetic acid solution, air flow, reaction time and the dosage of epichlorohydrin were investigated during synthesising. The satisfactory chitosan particles were prepared by chitosan–acetic acid solution (3%) under a controlled air flow of 0.6 m3 h−1, After 6 h of reaction at 80 °C with an epichlorohydrin dosage of 2 mL per 5 mL wet resin, the chitosan cross-linked resin has the best adsorption capacity. After 2 h of adsorption at pH = 3.0 and 25 °C with an adsorbent dosage of 2 g L−1, the maximum adsorption capacity (112 mg g−1) was reached for an initial Cr(VI) concentration of 146 mg L−1. Compared with other adsorbents, this synthesis method was simple and economic; moreover, the cross-linked chitosan resin can remove Cr(VI) efficiently.
Electrochemical degradation of 4-chlorophenol in aqueous solution using modified PbO2 anode
Authors: Duan X. Y. , Ma F. , Chang L. M.
Published: October 2012

The electrochemical oxidation of 4-chlorophenol (4-CP) in aqueous solution was studied by electrochemical oxidation using modified PbO2 electrode as anode. The influence of several operating parameters, such as initial 4-CP concentration, applied current density, and supporting electrolyte (Na2SO4) concentration was investigated. Ultraviolet spectroscopy and total organic carbon (TOC) measurements were conducted to study the kinetics of 4-CP electrochemical reaction and the mineralization efficiency of 4-CP. The experimental results showed that the 4-CP degradation always followed a pseudo-first-order kinetics. The higher mineralization of 4-CP and the lower current efficiency (CE) were obtained by the lower initial 4-CP concentration. The applied current density showed a positive influence on the degradation of 4-CP and the removal of TOC, but a higher applied current density led to a lower CE. Although Na2SO4 concentration of 0.05 M resulted in a higher 4-CP and TOC removal, the result of one-way analysis of variance (ANOVA) indicates that Na2SO4 concentration is not the significant parameter for 4-CP removal in electrochemical oxidation.
Analytical and numerical modelling of Newtonian and non-Newtonian liquid in a rotational cross-flow MBR
Authors: Bentzen T. R. , Ratkovich N. , Madsen S. , Jensen J. C. , Bak S. N. , Rasmussen M. R.
Published: October 2012

Fouling is the main bottleneck of the widespread use of MBR systems. One way to decrease and/or control fouling is by process hydrodynamics. This can be achieved by the increase of liquid cross-flow velocity. In rotational cross-flow MBR systems, this is attained by the spinning of, for example, impellers. Validation of the CFD (computational fluid dynamics) model was made against laser Doppler anemometry (LDA) tangential velocity measurements (error less than 8%) using water as a fluid. The shear stress over the membrane surface was inferred from the CFD simulations for water. However, activated sludge (AS) is a non-Newtonian liquid, for which the CFD model was modified incorporating the non-Newtonian behaviour of AS. Shear stress and area-weighted average shear stress relationships were made giving error less that 8% compared with the CFD results. An empirical relationship for the area-weighted average shear stress was developed for water and AS as a function of the angular velocity and the total suspended solids concentration. These relationships can be linked to the energy consumption of this type of systems.
Using reverse phase high performance liquid chromatography as an alternative to resin fractionation to assess the hydrophobicity of natural organic matter
Authors: Xing Linan , Lo Theodore , Fabris Rolando , Chow Christopher W. K. , van Leeuwen John , Drikas Mary , Wang Dongsheng
Published: October 2012

Resin fractionation is the most widely used technique to isolate and characterize natural organic matter (NOM) based on its hydrophobicity and hydrophilicity, however, it is also recognized as a time consuming technique. This paper describes the use of reverse phase high performance liquid chromatography (RPHPLC) as a rapid assessment technique to determine the hydrophobicity/hydrophilicity of NOM. The optimum column separation condition was achieved and without the need for concentrating the sample prior to analysis and with good reproducibility of the peak retention time and the peak area. The characterization results were further compared with the traditional resin fractionation technique using DAX-8 and XAD-4 resins. The results demonstrated that the polarities defined by the two methods were different but consistent and also that the fractions absorbed onto XAD-4 were less hydrophobic than those absorbed onto DAX-8. The difference in definition between resin fractionation and RPHPLC were further investigated.
Degradation of Bisphenol A Using UV and UV/H2O2 Processes
Authors: Felis Ewa , Ledakowicz Stanisław , Miller Jacek S.
Published: October 2012

Bisphenol A (BPA; 4‐[2‐(4‐hydroxyphenyl)propan‐2‐yl]phenol) is a substance typically used in the plastic industry. It is used in the production of epoxy resins, polycarbonate, or fire retardants or as a stabilizer and an antioxidant in numerous types of plastics. Bisphenol A is introduced into the environment via municipal and industrial wastewater. Because of its hydrophobic properties, BPA has the potential for sorption on activated sludge during the biological wastewater treatment processes. This study investigated the degradation of BPA by means of UV‐radiation and in the UV/H2O2 process with the presence and absence of hydrocarbonate ions (HCO3−) as hydroxyl radicals (OH•) scavengers. The calculated value of quantum yield was equal to 0.18, and the value of BPA rate constant with hydroxyl radicals was equal to 3.3 × 109 M−1•s−1.
Determination of the Nitrous Oxide Emission Potential of Deammonification under Anoxic Conditions
Authors: Schneider Y. , Beier M. , Rosenwinkel K‐H
Published: October 2012

Various studies have been performed to determine nitrous oxide (N2O) emissions from conventional biological nitrogen removal processes in wastewater treatment like nitrification and denitrification in the main stream. However, with respect to the overall emissions of a wastewater treatment plant, part‐stream treatment for high‐strength wastewater (e.g., sludge liquor) is also expected to hold a significant emission potential because of high concentrations and extreme boundary conditions. This paper presents results from a laboratory‐scale study on nitrous oxide production by biomass from a deammonification process (nitritation + anammox) under anoxic conditions. It was discovered that N2O formation results from incomplete endogenous denitrification rather than anammox and is dependent on substrate availability. Based on direct measurements of the dissolved N2O concentrations in a sequencing batch reactor, the dynamic behavior of N2O production is characterized in more detail. The results show that, during anoxic conditions, the N2O emission potential of deammonification is significantly lower than from conventional denitrification.
The Value of a Psychology Major: Bridging the Gap between Perceptions and Reality
Authors: Haskell Todd , Burrows Matthew , Harrington Chelsea , McCullough Kellyn , Schuh Kristin , Sperberg Andrea
Published: October 2012

In theory, a psychology major provides students with a set of skills that is highly valued by employers. In practice, however, US psychology majors fare relatively poorly in the job market. We hypothesised that one cause of this paradox may be a mismatch between student perceptions and the reality of the working world. To test this hypothesis, we first used existing data to determine what skills employers value most, and what types of jobs US psychology majors typically obtain. The results were compared with interview responses provided by US psychology majors near to graduation. This comparison revealed a substantial mismatch between perceptions and reality. One way to address this mismatch is through a careers course, and data are presented demonstrating that this approach can be effective. However, we argue that career preparation should not be considered as an isolated piece of the curriculum, but in the context of the larger debate regarding the appropriate goals for a college education.
Perron-Frobenius and Krein-Rutman theorems for tangentially positive operators
Authors: Kanigowski Adam , Kryszewski Wojciech
Published: October 2012

We study several aspects of a generalized Perron-Frobenius and Krein-Rutman theorems concerning spectral properties of a (possibly unbounded) linear operator on a cone in a Banach space. The operator is subject to the so-called tangency or weak range assumptions implying the resolvent invariance of the cone. The further assumptions rely on relations between the spectral and essential spectral bounds of the operator. In general we do not assume that the cone induces the Banach lattice structure into the underlying space.
The Inhibitor of Apoptosis (IAPs) in Adaptive Response to Cellular Stress
Authors: Marivin Arthur , Berthelet Jean , Plenchette Stéphanie , Dubrez Laurence
Published: October 2012

Cells are constantly exposed to endogenous and exogenous cellular injuries. They cope with stressful stimuli by adapting their metabolism and activating various “guardian molecules.” These pro-survival factors protect essential cell constituents, prevent cell death, and possibly repair cellular damages. The Inhibitor of Apoptosis (IAPs) proteins display both anti-apoptotic and pro-survival properties and their expression can be induced by a variety of cellular stress such as hypoxia, endoplasmic reticular stress and DNA damage. Thus, IAPs can confer tolerance to cellular stress. This review presents the anti-apoptotic and survival functions of IAPs and their role in the adaptive response to cellular stress. The involvement of IAPs in human physiology and diseases in connection with a breakdown of cellular homeostasis will be discussed.
Simulations of Infrared Radiances over a Deep Convective Cloud System Observed during TC4: Potential for Enhancing Nocturnal Ice Cloud Retrievals
Authors: Minnis Patrick , Hong Gang , Ayers J. Kirk , Smith William L. , Yost Christopher R. , Heymsfield Andrew J. , Heymsfield Gerald M. , Hlavka Dennis L. , King Michael D. , Korn Errol , McGill Matthew J. , Selkirk Henry B. , Thompson Anne M. , Tian Lin , Yang Ping
Published: October 2012

Retrievals of ice cloud properties using infrared measurements at 3.7, 6.7, 7.3, 8.5, 10.8, and 12.0 mm can provide consistent results regardless of solar illumination, but are limited to cloud optical thicknesses t < ~6. This paper investigates the variations in radiances at these wavelengths over a deep convective cloud system for their potential to extend retrievals of t and ice particle size De to optically thick clouds. Measurements from an imager, an interferometer, the Cloud Physics Lidar (CPL), and the Cloud Radar System (CRS) aboard the NASA ER-2 aircraft during the NASA TC4 (Tropical Composition, Cloud and Climate Coupling) experiment flight during 5 August 2007, are used to examine the retrieval potential of infrared radiances over optically thick ice clouds. Simulations based on coincident in situ measurements and combined cloud t from CRS and CPL measurements are comparable to the observations. They reveal that brightness temperatures at these bands and their differences (BTD) are sensitive to t up to ~20 and that for ice clouds having t > 20, the 3.7–10.8 µm and 3.7–6.7 µm BTDs are the most sensitive to De. Satellite imagery appears to be consistent with these results suggesting that t and De could be retrieved for greater optical thicknesses than previously assumed. But, because of sensitivity of the BTDs to uncertainties in the atmospheric profiles of temperature, humidity, and ice water content, and sensor noise, exploiting the small BTD signals in retrieval algorithms will be very challenging.
On the Notions of Symmetry and Aperiodicity for Delone Sets
Authors: Baake Michael , Grimm Uwe
Published: October 2012

Non-periodic systems have become more important in recent years, both theoretically and practically. Their description via Delone sets requires the extension of many standard concepts of crystallography. Here, we summarise some useful notions of symmetry and aperiodicity, with special focus on the concept of the hull of a Delone set. Our aim is to contribute to a more systematic and consistent use of the different notions.
The “New palace guards:” Elections and Elites in Morocco and Jordan
Authors: Barwig Andrew
Published: October 2012

In 2007, parliamentary elections in Jordan and Morocco marked the emergence of business-minded elites and technocrats who attempted to enact reform from within parliament but remained loyal to the regime. Using Albert Hirschman's framework of “exit, voice and loyalty,” this
article argues that the decisions of these “new elites” are in part a function of electoral systems. In particular, personalistic electoral systems encourage political actors to play by the rules and produce “loyalty” outcomes because they ensure patronage benefits.
This incentive structure provides some insights into the logic of electoral reform and the relative stability of these two monarchies in contrast to the defection of elites during parliamentary elections in Egypt and the Palestinian Territories around the same time.
Learners’ perceptions of learners regarded as having a homosexual orientation in an independent secondary school environment
Authors: Mostert Hendrik P. , Myburgh Chris , Poggenpoel Marie
Published: October 2012

In schools today discrimination based on sexual orientation takes place on a regular basis. This form of discrimination leads to aggression towards learners perceived to be homosexual, as well as towards those with a homosexual orientation. For more than 15 years South Africa has been a democratic country with laws that protect learners who have a homosexual orientation. Nevertheless, aggression and discrimination towards these learners still occur in schools. Aggression often leads to verbal and physical bullying of the victims by perpetrators. The objectives of this research were to explore and describe Grade 11 learners’ experiences of aggression towards learners perceived to be homosexual as well as those with a homosexual orientation in an independent secondary school environment. The research design was qualitative, exploratory, descriptive and contextual in nature. The data for this investigation consisted of essays based on a published newspaper photograph, phenomenological group interviews, observations and field notes. Tesch’s method of data analysis was used, and an independent coder assisted. Three themes were identified, discussed and supported by a literature control: that learners experience that it is right and acceptable to have a homosexual orientation; that they experience ambivalence towards homosexual orientation of learners; and experienced feelings that it is wrong to have a homosexual orientation. Recommended guidelines are provided to address aggression towards learners perceived to be homosexual and those with a homosexual orientation.
Cigarette Smoking and Alcohol Ingestion as Risk Factors for Laryngeal Squamous Cell Carcinoma at Kenyatta National Hospital, Kenya
Authors: Menach Pyeko , Oburra Herbert O. , Patel Asmeeta
Published: October 2012

Laryngeal squamous cell carcinoma (SCC) is strongly linked to cigarette smoking. It is estimated to account for more than 70% of laryngeal SCCs and up to 89% in combination with alcohol. We wished to determine the prevalence of cigarette smoking and alcohol ingestion among patients with laryngeal squamous cell carcinoma and estimate risk attributed to cigarette smoking and alcohol ingestion. Fifty experimental group patients and fifty controls were recruited of matching age, sex and region of residence. History of smoking and alcohol intake was taken and analyzed to estimate the relative strengths of these exposures. Cessation of smoking was associated with reduced risk of SCC. Smokers had increased risk compared to controls. Those who smoked only had a higher glottic cancer risk. Those who smoked and drank alcohol had a higher supraglottic cancer risk. Being a current smoker and long duration of smoking were independent risk factors of laryngeal SCC.
Frustule‐related gene transcription and the influence of diatom community composition on silica precipitation in an iron‐limited environment
Authors: Durkin Colleen A. , Marchetti Adrian , Bender Sara J. , Truong Tiffany , Morales Rhonda , Mock Thomas , Armbrust E. Virginia
Published: October 2012

A microcosm study in iron‐limited waters of the northeast subarctic Pacific Ocean was conducted to examine how iron availability affects the frustule‐related response of individual diatoms and thus the total quantity of silica precipitated by the community. New silica precipitated per cell was estimated using the fluorescent cell stain 2‐(4‐pyridyl)‐5{[4‐dimethylaminoethyl‐aminocarbamoyl)‐methoxy]phenyl}oxazole (PDMPO). Differences in new silica precipitation within a particular genus before and after iron enrichment were small compared to differences among genera, indicating that the quantity of total silica precipitated is particularly sensitive to community composition. Transcriptional patterns of genes encoding silicon transporters, aminopropyltransferases, chitin synthases, and a protein with uncharacterized function were measured in natural populations to identify indicators of the frustule‐related responses of different genera to iron limitation. Transcripts associated with silicon transporters were the most readily detectable in three metatranscriptome datasets and were capable of resolving species composition shifts and physiological responses. Silicon transporter transcripts from a distinct phylogenetic clade were most abundant in the iron‐limited community, and transcripts from a separate clade were more abundant in the community that bloomed after iron enrichment. Transcripts of the gene present in the iron‐limited community were also more abundant in iron‐limited laboratory cultures of Pseudo‐nitzschia multiseries, suggesting that this gene plays a role in silicon uptake during iron limitation. The responses of individual cells, as detected in this study, determine how the community influences silicon cycling in iron‐limited environments.
Global anthropogenic methane emissions 2005–2030: technical mitigation potentials and costs
Authors: Höglund-Isaksson L.
Published: October 2012

Abstract. This paper presents estimates of current and future global anthropogenic methane emissions, their technical mitigation potential and associated costs for the period 2005 to 2030. The analysis uses the GAINS model framework to estimate emissions, mitigation potentials and costs for all major sources of anthropogenic methane for 83 countries/regions, which are aggregated to produce global estimates. Global emissions are estimated at 323 Mt methane in 2005, with an expected increase to 414 Mt methane in 2030. The technical mitigation potential is estimated at 195 Mt methane in 2030, whereof about 80 percent is found attainable at a marginal cost less than 20 Euro t−1 CO2eq when using a social planner cost perspective. With a private investor cost perspective, the corresponding fraction is only 30 percent. Major uncertainty sources in emission estimates are identified and discussed.
Radiative impacts of cloud heterogeneity and overlap in an atmospheric General Circulation Model
Authors: Oreopoulos L. , Lee D. , Sud Y. C. , Suarez M. J.
Published: October 2012

Abstract. The radiative impacts of horizontal heterogeneity of layer cloud condensate, and vertical overlap of both condensate and cloud fraction are examined with the aid of a new radiation package operating in the GEOS-5 Atmospheric General Circulation Model. The impacts are examined in terms of diagnostic top-of-the atmosphere shortwave (SW) and longwave (LW) cloud radiative effect (CRE) calculations for a range of assumptions and overlap parameter specifications. The investigation is conducted for two distinct cloud schemes, one that comes with the standard GEOS-5 distribution, and another used experimentally for its enhanced cloud microphysical capabilities. Both schemes are coupled to a cloud generator allowing arbitrary cloud overlap specification. Results show that cloud overlap radiative impacts are significantly stronger in the operational cloud scheme where a change of cloud fraction overlap from maximum-random to generalized results in global changes of SW and LW CRE of ~4 Wm−2, and zonal changes of up to ~10 Wm−2. This is an outcome of fewer occurrences (compared to the other scheme) of large layer cloud fractions and fewer multi-layer situations where large numbers of atmospheric layers are simultaneously cloudy, both conditions that make overlap details more important. The impact of the specifics of condensate distribution overlap on CRE is much weaker. Once generalized overlap is adopted, both cloud schemes are only modestly sensitive to the exact values of the overlap parameters. When one of the CRE components is overestimated and the other underestimated, both cannot be driven simoultaneously towards observed values by adjustments to cloud condensate heterogeneity and overlap specifications alone.
Commentary on using equivalent latitude in the upper troposphere and lower stratosphere
Authors: Pan L. L. , Kunz A. , Homeyer C. R. , Munchak L. A. , Kinnison D. E. , Tilmes S.
Published: October 2012

Abstract. We discuss the use of potential vorticity (PV) based equivalent latitude (EqLat) and potential temperature (θ) coordinates in the upper troposphere and lower stratosphere (UTLS) for chemical transport studies. The main objective is to provide a cautionary note on using EqLat-θ coordinates for aggregating chemical tracers in the UTLS. Several examples are used to show 3-D distributions of EqLat together with chemical constituents for a range of θ. We show that the use of PV-θ coordinates may not be suitable for several reasons when tropospheric processes are an important part of a study. Due to the different static stability structures between the stratosphere and troposphere, the use of θ as a vertical coordinate does not provide equal representations of the UT and LS. Since the θ surfaces in the troposphere often intersect the surface of the Earth, the θ variable does not work well distinguishing the UT from the boundary layer when used globally as a vertical coordinate. We further discuss the duality of PV/EqLat as a tracer versus as a coordinate variable. Using an example, we show that while PV/EqLat serves well as a transport tracer in the UTLS region, it may conceal the chemical structure associated with wave breaking when used as a coordinate to average chemical tracers. Overall, when choosing these coordinates, considerations need to be made not only based on the time scale of PV being a conservative tracer, but also the specific research questions to be addressed.
Optical properties of Saharan dust aerosol and contribution from the coarse mode as measured during the Fennec 2011 aircraft campaign
Authors: Ryder C. L. , Highwood E. J. , Rosenberg P. D. , Trembath J. , Brooke J. K. , Bart M. , Dean A. , Crosier J. , Dorsey J. , Brindley H. , Banks J. , Marsham J. H. , McQuaid J. B. , Sodemann H. , Washington R.
Published: October 2012

Abstract. New in-situ aircraft measurements of Saharan dust originating from Mali, Mauritania and Algeria taken during the Fennec 2011 aircraft campaign over a remote part of the Sahara Desert are presented. Size distributions extending to 300 μm are shown, representing measurements extending further into the coarse mode than previously published for airborne Saharan dust. A significant coarse mode was present in the size distribution measurements with effective diameter (deff) from 2.3 to 19.4 μm and coarse mode volume median diameter (dvc) from 5.8 to 45.3 μm. The mean size distribution had a larger relative proportion of coarse mode particles than previous aircraft measurements. The largest particles (with deff > 12 μm, or dvc > 25 μm) were only encountered within 1 km of the ground. Number concentration, mass loading and extinction coefficient showed inverse relationships to dust age since uplift. Dust particle size showed a weak exponential relationship to dust age. Two cases of freshly uplifted dust showed quite different characteristics of size distribution and number concentration. SSA values at 550 nm calculated from the measured size distributions revealed high absorption ranging from 0.70 to 0.97 depending on the refractive index. SSA was found to be strongly related to deff. New instrumentation revealed that direct measurements, behind Rosemount inlets, overestimate SSA by up to 0.11 when deff is greater than 2 μm. This is caused by aircraft inlet inefficiencies and sampling losses. Previous measurements of SSA from aircraft measurements may also have been overestimates for this reason. Radiative transfer calculations indicate that the range of SSAs during Fennec 2011 can lead to underestimates in shortwave atmospheric heating rates by 2.0 to 2.9 times if the coarse mode is neglected. This will have an impact on Saharan atmospheric dynamics and circulation, which should be taken into account by numerical weather prediction and climate models.
Optimising the FAMOUS climate model: inclusion of global carbon cycling
Authors: Williams J. H. T. , Smith R. S. , Valdes P. J. , Booth B. B. B. , Osprey A.
Published: October 2012

Abstract. FAMOUS fills an important role in the hierarchy of climate models, both explicitly resolving atmospheric and oceanic dynamics yet being sufficiently computationally efficient that either very long simulations or large ensembles are possible. An improved set of carbon cycle parameters for this model has been found using a perturbed physics ensemble technique. This is an important step towards building the "Earth System" modelling capability of FAMOUS, which is a reduced resolution, and hence faster running, version of the Hadley Centre Climate model, HadCM3. Two separate 100 member perturbed parameter ensembles were performed; one for the land surface and one for the ocean. The land surface scheme was tested against present day and past representations of vegetation and the ocean ensemble was tested against observations of nitrate. An advantage of using a relatively fast climate model is that a large number of simulations can be run and hence the model parameter space (a large source of climate model uncertainty) can be more thoroughly sampled. This has the associated benefit of being able to assess the sensitivity of model results to changes in each parameter. The climatologies of surface and tropospheric air temperature and precipitation are improved relative to previous versions of FAMOUS. The improved representation of upper atmosphere temperatures is driven by improved ozone concentrations near the tropopause and better upper level winds.
The impact of model and rainfall forcing errors on characterizing soil moisture uncertainty in land surface modeling
Authors: Maggioni V. , Anagnostou E. N. , Reichle R. H.
Published: October 2012

Abstract. The contribution of rainfall forcing errors relative to model (structural and parameter) uncertainty in the prediction of soil moisture is investigated by integrating the NASA Catchment Land Surface Model (CLSM), forced with hydro-meteorological data, in the Oklahoma region. Rainfall-forcing uncertainty is introduced using a stochastic error model that generates ensemble rainfall fields from satellite rainfall products. The ensemble satellite rain fields are propagated through CLSM to produce soil moisture ensembles. Errors in CLSM are modeled with two different approaches: either by perturbing model parameters (representing model parameter uncertainty) or by adding randomly generated noise (representing model structure and parameter uncertainty) to the model prognostic variables. Our findings highlight that the method currently used in the NASA GEOS-5 Land Data Assimilation System to perturb CLSM variables poorly describes the uncertainty in the predicted soil moisture, even when combined with rainfall model perturbations. On the other hand, by adding model parameter perturbations to rainfall forcing perturbations, a better characterization of uncertainty in soil moisture simulations is observed. Specifically, an analysis of the rank histograms shows that the most consistent ensemble of soil moisture is obtained by combining rainfall and model parameter perturbations. When rainfall forcing and model prognostic perturbations are added, the rank histogram shows a U-shape at the domain average scale, which corresponds to a lack of variability in the forecast ensemble. The more accurate estimation of the soil moisture prediction uncertainty obtained by combining rainfall and parameter perturbations is encouraging for the application of this approach in ensemble data assimilation systems.
Floods and wetlands: combining a water-balance model and remote-sensing techniques to characterize hydrological processes of ecological importance in the Tana River Delta (Kenya)
Authors: Leauthaud C. , Duvail S. , Belaud G. , Moussa R. , Grünberger O. , Albergel J.
Published: October 2012

Abstract. The Tana River Delta (TRD) provides a multitude of ecosystem services for the local communities including fishing, farming and livestock keeping. The hydrological regime of its river determines for a large part the environmental health of the delta. The development of upstream irrigation schemes and hydroelectric infrastructure can seriously impact the ecological status of the TRD. The Tana Inundation Model (TIM) presented here is the first known hydrological model of the TRD. Using it, we quantify essential hydrological variables of ecological importance for 2002–2011 such as flood extent and duration, flood timing and frequency, flood peaks and water height. TIM also provides an annual water balance. The model simulates river inflows and outflows, precipitation, overland flow, evapotranspiration and infiltration. The TRD is characterized by scarce hydrological data and a high cloud cover limiting the use of many remote sensing techniques. The methodology therefore combined a conventional water-balance analysis with the extraction of inundation extents from MODIS satellite imagery at a medium spatial and temporal resolution. In non extreme years and for the actual configuration of the Tana River, the flooded area exceeds 560 km2. Floods over 200 km2 occur approximately every two years, with a mean duration of less than 25 days. River discharge from the upper catchment counts for over 96% of the total water inflow. This study provides the first known estimates of these variables for the Tana River Delta and is therefore primordial for the management of the water and other natural resources of the zone. The hydrological model based on the Generalized Likelihood Uncertainty Estimation (GLUE) is generic enough to be applied to other catchments with scarce hydrological data.
Incorporation of rating curve uncertainty in dynamic identifiability analysis and model structure evaluation
Authors: Van Hoey S. , Seuntjens P. , van der Kwast J. , Nopens I.
Published: October 2012

Abstract. When applying hydrological models, different sources of uncertainty are present and the incorporation of these uncertainties in evaluations of model performance are needed to assess model outcomes correctly. Nevertheless, uncertainty in the discharge observations complicate the model identification, both in terms of model structure and parameterization. In this paper, two different lumped model structures (PDM and NAM) are compared taking into account the uncertainty coming from the rating curve. The derived uncertainty bounds of the observations are used to derive limits of acceptance for the model simulations. The DYNamic Identifiability Approach (DYNIA) is applied to identify structural failure of both models and to evaluate the configuration of their structures. The analysis focuses on different parts of the hydrograph and evaluates the seasonal performance. In general, similar model performance is observed. However, the model structures tend to behave differently in function of the time. Based on the analyses we did, the probability based soil storage representation of the PDM model outperformed the NAM structure. The incorporation of the observation error did not prevent the DYNIA analysis to identify potential model structural deficiencies that are limiting the representation of the seasonal variation.
Visual Prognosis and Complications following Silicone Oil Removal
Authors: Moisseiev Elad , Ohana Oded , Gershovitch Liron , Barak Adiel
Published: October 2012

Purpose.

To evaluate the visual prognosis and the occurrence of significant complications after silicone oil removal (SOR) in recent years and compare them to previously published data.

Methods.

A total of 89 eyes of 89 patients who underwent SOR and had at least 6 months of follow-up were included in this retrospective study. Recorded parameters included demographic information, previous ocular history, length of silicone oil retention in the eye, visual acuity (VA) and intraocular pressure (IOP) prior to the SOR procedure and throughout the follow-up period, and the occurrence of postoperative complications.

Results.

Indications for silicone oil injection included perforating trauma (9%), proliferative diabetic retinopathy (PDR) (6.7%), giant tear (7.8%), and rhegmatogenous retinal detachment (RRD) (76.5%). After SOR, RRD, keratopathy, persistent hypotony, and elevated IOP occurred at rates of 21.3%, 11.2%, 10.1%, and 9%, respectively. Eyes with preoperative hypotony were significantly more likely to have persistent hypotony and a poor visual prognosis.

Discussion.

Our results provide a thorough contemporary analysis of the visual prognosis and complication rates after SOR. Avoiding SOR with long-term silicone oil retention may be advisable in hypotonous eyes.
Decálogo del Docente Universitario
Authors: Bernheim Carlos Tünnermann
Published: October 2012

Cefas Asensio Flórez comenta el Decálogo del Docente Universitario, propuesto por el gran educador nicaragüense, Dr. Carlos Tünnerman Bernheim, surgido de una vida dedicada al quehacer educativo y su conocimiento a fondo de la temática de la educación superior. DOI: http://dx.doi.org/10.5377/cultura.v18i57.799 Cultura de Paz • Año XVIII • N° 57 • Mayo - Agosto 2012 P / 27-35
Manifiesto de Barcelona por la paz
Authors: Editor El
Published: October 2012

DOI: http://dx.doi.org/10.5377/cultura.v18i57.802 Cultura de Paz • Año XVIII • N° 57 • Mayo - Agosto 2012 P / 43-46
Pensar la historia
Authors: Silva Erwin
Published: October 2012

Este es el primero de tres artículos consecutivos sobre la filosofía de la Historia. El propósito de este primer artículo es presentar desde la filosofía de la historia un posible origen de la historia en la cultura occidental y un somero recorrido por algunos de los exponentes de esta Ciencia y de cómo se convierte la historia en historia escrita. DOI: http://dx.doi.org/10.5377/cultura.v18i57.803 Cultura de Paz • Año XVIII • N° 57 • Mayo - Agosto 2012 P / 47-48
El Saqueo del Museo de Irak
Authors: Cardenal Ernesto
Published: October 2012

DOI: http://dx.doi.org/10.5377/cultura.v18i57.804 Cultura de Paz • Año XVIII • N° 57 • Mayo - Agosto 2012 P / 49-51
Distribution and ecology of the lichen Fellhanera gyrophorica in the Pojezierze Olsztyńskie Lakeland and its status in Poland
Authors: Kubiak Dariusz
Published: October 2012

The study presents recent data on the distribution of Fellhanera gyrophorica (Pilocarpaceae, Ascomycota) in Poland, a rare lichen with a crustose, usually sterile thallus. Both previous and new localities of the species are presented with data on its eco­logy and general distribution. Furthermore, this paper provides detailed results on floristic investigations of the species in the forest areas of the Pojezierze Olsztyńskie Lakeland (Northern Poland). Fertile specimens of F. gyrophorica have been observed in Poland for the second time and in the world – for the third time. Also, a new substrate for this species has been found: Acer platanoides. In addition, Carpinus betulus and Populus tremula were also found to be the species' substrates in Poland. Based on this study and previous reports, F. gyrophorica seems to be a relatively common species in north-eastern Poland.
Girolamo e l'epistolario tra Seneca e san Paolo
Authors: Grappone Antonio ,   Instituto Patristico Augustinianum
Published: October 2012

The article begins by noting that the first mention of the Correspondence between Seneca and Paul appears in De viris illustribus of Jerome. After a summary of the status quaestionis, it examines the context of the De viris, particularly the information on Seneca. Then the article presents an analysis of some aspects of the Correspondence in order to highlight the harmony between the views of the Correspondence and the ideas of Jerome, especially the considerations on the inadequacy of the language of the Pauline letters. After finding other reasons of convergence, we formulate a hypothesis about the origin of the Correspondence.
The Morality of Disgust in Jerome and John Chrysostom
Authors: Wessel Susan ,   Instituto Patristico Augustinianum
Published: October 2012

Jerome and John Chrysostom explored the disgust and revulsion that people often feel when confronted with the suffering of another human being. Theyattempted morally to reform their listeners by showing them that they were just as vulnerable as those whom they disparaged, and by breaking down false barriers between the self and other. Jerome presented graphic details of one woman’s ministry to the sick and poor, while Chrysostom criticized the aloofspectator who encouraged the sick and poor to perform. Disgust was thereby re-conceived as an inappropriate response to human suffering.
Ricordando Marta Sordi
Authors: De Simone Pia ,   Instituto Patristico Augustinianum
Published: October 2012

Between November 11 and 13, 2009, the conference Dal logos dei Greci e dei Romani al logos di Dio was held at the Università Cattolica del Sacro Cuore(in Milan) in memory of Marta Sordi. The meeting is part of a multi-year project of dialogue and analysis exploring philosophical, religious, historical and political issues that were as widespread in classical and late antiquity as they are currently of concern in contemporary debate. The meeting explored the word logos, that has his roots in the classical world before being adopted and used by Christianity as its own. The following report includes references from all participants’ papers.
Christian Liturgical Time and Torture (Cod. Theod. 9,35,4 and 5)
Authors: Di Berardino Angelo ,   Instituto Patristico Augustinianum
Published: October 2012

On the 3rd of March 380, Theodosius, moved by the qualitas (pro reverentia religionis) of the pre-paschal period, a special time of preparation for Easter,mandates the suspension during Christian Lent of all penal trials which normally resulted in torture (Cod. Theod. 9,35,4 = Cod. Iust. 3,12,5). Lent is a specifically Christian time which developed to a large degree in the course of the fourth century, but which varied in duration and organization in the various churches. The law adapts the judicial calendar for the administration of justice to the rhythms of Christian liturgy. Theodosius in 389 (Cod. Theod. 9,35,5; 9,35,7) decrees that during Lent supplicia corporis could not take place, due to the sacredness of those days intended as a salutary penance which culminates in Easter reconciliation. Since the duration of Lent varied within the various churches, civil authorities of the provinces were to be informed by local Christians of the beginning and end of Lent.