Change Management Models: Commonalities and Key Challenges in the Industry

It can be argued that managing change is crucial for any organisation to survive and succeed in the present highly competitive and continuously evolving business environment. However, theories and approaches to change management currently available to academics and practitioners are often contradictory, mostly lacking empirical evidence and supported by unchallenged hypotheses concerning the nature of contemporary organisational change management. This paper seeks to understand the key challenges faced when implementing change management projects in the industry, especially in aerospace, and the commonalities across existing change management methodologies. The paper describes results from interviews with industry experts and the literature review to provide a discerning sight of the challenges faced when implementing change management projects and the components shared by the available methodologies

Caracterización de la población de Fusarium oxysporum f. sp. dianthi en la costa Noroeste de Cádiz y control mediante composts supresivos de las marchiteces vasculares

Las marchiteces vasculares constituyen uno de los tipos de enfermedades vegetales más importantes y estudiadas de las causadas por hongos. Los principales agentes causantes de este tipo de enfermedad son: Fusarium oxysporum (Schlecht ex Fries) (Fusariosis vasculares) y Verticillium dahliae Kleb. (Verticilosis vasculares). En la búsqueda de alternativas sostenibles, las sociedades desarrolladas generan una gran cantidad de residuos orgánicos procedentes de la industria agrícola. Estos residuos tras un proceso de compostaje podrían ser usados como sustratos hortícolas. Además, algunos composts de alta calidad o bien sustratos enriquecidos con agentes de control biológico inciden disminuyendo las enfermedades producidas por algunos de los principales hongos fitopatógenos, siendo además una alternativa al Bromuro de Metilo en los cultivos en contenedor, presentando un fenómeno denominado supresividad. En este sentido, la presente Tesis Doctoral se desglosa en dos objetivos: el estudio de la diversidad y prevalencia racial de una población de Fusarium oxysporum f. sp. dianthi (Fod) obtenida de plantas enfermas en una zona con una alta tradición en el cultivo del clavel (Noroeste de la provincia de Cádiz); y la evaluación de sustratos formulados con composts de residuos agroindustriales en cuatro patosistemas (Fusarium/clavel, Fusarium/tomate, Verticillium/algodón y Verticillium/olivo) y el estudio de los factores implicados en esos fenómenos supresivos.We surveyed the diversity of races and prevalence of pathogenic populations of Fusarium oxysporum f. sp. dianthi (Fod) in an area in the northwest of the province of Cadiz (Spain). From 54 farms, 132 isolates were collected from wilted carnation plants. Molecular techniques, namely phylogenetic studies [using RAPD-PCR fingerprinting and sequencing of the transcription elongation factor (TEF1-α)] and analysis with racespecific molecular markers were used to characterize these isolates. Selected isolates from RAPD groups were phenotypically evaluated by pathogenicity tests. All these data showed that Fod race 2 was the most frequent and prevalent race in the study area, followed by race 1 or 8. Moreover, phylogenetic analyses showed similar results, which were different to those of the race-specific PCR assays. Three findings were highlights from these results: i) seven isolates were not classified in groups where Fod testers were clustered, even they showed different results when race-specific markers were used, ii) ten isolates with retarded race 1 or 8 specific-band were characterized as F. proliferatum by TEF1-α gene sequencing and clustered into an outgroup, and iii) six isolates failed to generate an amplification signal using race-specific markers. Furthermore, three of them were grouped close to the race 2 tester according to the phylogenetic analyses, and showed the same differential pathogenicity as race 2. This may indicate the presence of a Fod race 2 subgroup in this region

Genome scale metabolic modeling reveals the metabolic potential of three Type II methanotrophs of the genus Methylocystis

Producción CientíficaGenome Scale Metabolic Models (GSMMs) of the recently sequenced Methylocystis hirsuta and two other methanotrophs from the genus Methylocystis have been reconstructed. These organisms are Type II methanotrophs with the ability of accumulating Polyhydroxyalkanoates under nutrient limiting conditions. For the first time, GSMMs have been reconstructed for Type II methanotrophs. These models, combined with experimental biomass and PHB yields of Methylocystis hirsuta, allowed elucidating the methane oxidation mechanism by the enzyme pMMO (particulate methane monooxygenase) in these organisms. In contrast to Type I methanotrophs, which use the “direct coupling mechanism”, Type II methanotrophs appear to use the so called “redox arm mechanism”. The utilization of the “redox arm mechanism”, which involves the coupling between methane oxidation and complex I of the respiratory chain, was confirmed by inhibition of complex I with catechol. Utilization of the “redox arm” mechanism leads to lower biomass yields on methane compared to Type I methanotrophs. However, the ability of Type II methanotrophs to redirect high metabolic carbon fluxes towards acetoacetyl-CoA under nitrogen limiting conditions makes these organisms promising platforms for metabolic engineering.Marie Curie grant H2020-MSCA-IF-2016 CH4BioVal (GA nº 750126).Junta de Castilla y León (Ref. Project VA281P18)Ministerio de Ciencia e Innovación (Proyect CLU 2017-09, CTM2015-70442-R

El cambio político en México: del presidencialismo autoritario al pacto por México (1926-2012)

El presente trabajo de investigación tiene como objetivo el documentar los principales elementos característicos del cambio político en nuestro país a partir de la etapa del presidencialismo hegemónico del PRI y hasta la implementación del “Pacto por México” así como las primeras reformas derivadas de este, comprendiendo de 1929 a 2012. Para la elaboración del presente texto, se empleó una metodología de carácter documental, la cual permitió el puntualizar de manera concisa los acontecimientos que de manera directa influyeron en una nueva configuración del sistema político mexicano, que pasó de ser un sistema político caracterizado por el dominio hegemónico de un solo partido político, el PRI, a ser un sistema político caracterizado por una pluralidad política y competitividad electoral, como consecuencia de una serie de reformas políticas y electorales que permitieron una alternancia en el poder ejecutivo de México. Las reformas electorales y al sistema de partidos en México, a su vez permitieron que el Congreso de la Unión ya no estuviese sumido al poder ejecutivo por la pluralidad partidista presente, por lo que la actividad legislativa, a partir de 1997 entró en una etapa en donde alcanzar acuerdos para realizar modificaciones constitucionales de suma importancia para el país se tornaba complicado debido a los distintos intereses e ideologías de los partidos presentes en las Cámaras del Congreso. En el presente trabajo se parte del supuesto de que el “Pacto por México” surge como la alternativa que ha permitido encontrar coincidencias para realizar reformas necesarias para el país

Odour prevention strategies in wastewater treatment plants: A pilot scale study of activated sludge recycling and oxidized nitrogen recycling

Producción CientíficaThe potential of activated sludge recycling (ASR) and oxidized nitrogen recycling (ONR) to prevent the emissions of H2S and acetic acid from the primary settler during domestic wastewater treatment was herein evaluated. The pilot plant consisted of an 8 L primary settler with a 10 L gas-tight headspace coupled to a 11 L nitrification-denitrification activated sludge reactor and an 8 L secondary settler, which were monitored for 175 days. A reduction in the headspace concentrations of H2S and acetic acid by 95 % and 42 %, respectively, was recorded when combining ASR and ONR. Process operation with ASR and ONR supported stable conditions with average organic matter removals of 96 ± 2 %, NO2- concentrations of 24.2 ± 0.4 mg N/L and NO3- concentrations of 9.8 ± 0.4 mg N/L in the effluent, and a biological oxidation of S2- higher than 99 % with average SO42- concentrations of 52 ± 8 mg/L. Interestingly, the sole recirculation of activated sludge to the primary settler without NO3- recycling caused sludge bulking, contributing to increase the concentration of H2S and acetic acid in the primary settler headspace up to 0.99 ± 0.01 ppmv and 2.87 ± 0.12 ppmv, respectively. Sludge bulking also resulted in an increase in the effluent soluble total nitrogen concentration from 5.6 ± 0.1 mg N/L to 50.8 ± 0.2 mg N/L and of NH4+ from 1.3 ± 0.2 mg N/L to 50.7 ± 0.8 mg N/L due to the loss of nitrification under these operational conditions. Overall, the experimental results indicated that ASR and ONR represent cost-effective strategies for the control of malodorous emissions in wastewater treatment plants.Junta de Castilla y León - EU-FEDER (CLU 2017-09, CL-EI-2021-07 y UIC 315)Ministerio de Ciencia e Innovación (FJC2019-039791-I

Influence of organic matter and CO2 supply on bioremediation of heavy metals by Chlorella vulgaris and Scenedesmus almeriensis in a multimetallic matrix

Producción CientíficaThis research evaluated the influence of organic matter (OM) and CO2 addition on the bioremediation potential of two microalgae typically used for wastewater treatment: Chlorella vulgaris (CV) and Scenedesmus almeriensis (SA). The heavy metal (HM) removal efficiencies and biosorption capacities of both microalgae were determined in multimetallic solutions (As, B, Cu, Mn, and Zn) mimicking the highest pollutant conditions found in the Loa river (Northern Chile). The presence of OM decreased the total biosorption capacity, specially in As (from 2.2 to 0.0 mg/g for CV and from 2.3 to 1.7 mg/g for SA) and Cu (from 3.2 to 2.3 mg/g for CV and from 2.1 to 1.6 mg/g for SA), but its influence declined over time. CO2 addition decreased the total HM biosorption capacity for both microalgae species and inhibited CV growth. Finally, metal recovery using different eluents (HCl, NaOH, and CaCl2) was evaluated at two different concentrations. HCl 0.1 M provided the highest recovery efficiencies, which supported values over 85% of As, 92% of Cu, and ≈100% of Mn and Zn from SA. The presence of OM during the loaded stage resulted in a complete recovery of As, Cu, Mn, and Zn when using HCl 0.1 M as eluent.Gobierno regional de Castilla y León (UIC 071, CLU 2017-09 and VA080G18)Ministerio de Ciencia, Innovación y Universidades (project CTQ2017-84006-C3-1-R)Unión Europea - FEDER (CLU 2017-09 and CTQ2017-84006-C3-1-R

Optimization of activated sludge recycling and oxidized ammonium recycling as odour control strategies in wastewater treatment plants

Producción CientíficaNew odour prevention strategies in wastewater treatment facilities need to be investigated to find effective and low-cost technologies for the control of malodorous emissions. In this study, the potential of activated sludge (AS) and oxidized nitrogen (N-NOx) recycling as an environmentally-friendly and cost-effective strategy for the prevention and minimization of odour nuisance during wastewater treatment was evaluated and optimized using H2S, acetic acid and α-pinene as model odorants in 2.1 L gas tight bottles. This approach uses by-products from wastewater treatment to mitigate odour annoyance. Preliminary abiotic tests showed headspace concentration losses of 25% for H2S and α-pinene, and 7% for acetic acid due to odorant adsorption in 4 h. The experiments carried out at different concentrations of AS (0, 10, 25, 50, 100 mg VSS/L) and oxidized nitrogen (1.5, 5, 7.5 and 10 mg N-NOx/L) revealed an effective H2S removal at 7.5–10 mg N-NOx/L and 50–100 mg VSS/L. Interestingly, NO3− was more effective than NO2− as electron acceptor during the biodegradation of H2S regardless of the AS concentration and N-NOx concentrations. In the presence of dissolved H2S and AS concentrations of 50–100 mg VSS/L, acetic acid was partially metabolized by microorganisms at the end of experiment (from 27 to 23 ppmv in 4.5 h), while α-pinene concentrations experienced a similar gradual decrease than in the abiotic tests. Finally, the assays carried out at concentrations ≥5 mg NO3−/L and 25 mg VSS/L showed a reduction of NO3− to NO2− correlated with the biological oxidation of H2S, which suggested the need to control NO3− supply under sulphur limiting conditions to prevent toxicity problems during wastewater treatment.Junta de Castilla y León (grants CLU 2017-09 and UIC 315)Ministerio de Ciencia e Innovación (project FJC2019-039791-I)

Guidelines for the Specification and Design of Large-Scale Semantic Applications

This paper presents a set of guidelines to help software engineers with the specification and design of large-scale semantic applications by defining new processes for Requirements Engineering and Design for semantic applications. To facilitate its use to software engineers not experts in semantic technologies, several techniques are provided, namely, a characterization of large-scale semantic applications, common use cases that appear when developing this type of application, and a set of architectural patterns that can be used for modelling the architecture of semantic applications. The paper also presents an example of how these guidelines can be used and an evaluation of our contributions using the W3C Semantic Web use cases

Two-phase partitioning bioreactors: towards a new generation of high-performance biological processes for VOC and CH4 abatement.

The intense research and development conducted over the past 30 years in the field of air pollution control have increased the acceptance of biotechnologies as cost-efficient technological solutions to mitigate atmospheric pollution. Despite the low operating cost of biofilters and biotrickling filters, the limited mass transfer rates of certain key air contaminants from the gas phase to the microbial community and the perceived limited robustness of biotechnologies still make physical-chemical technologies the preferred methods for air pollution control. In this context, the addition of a non-aqueous phase to conventional bioreactors, in the so called two-phase partitioning bioreactors (TPPBs), can overcome the above mentioned limitations and trigger the consolidation of biotechnologies for the removal of odors, volatile organic contaminants (VOCs) or greenhouse gases. TPPBs have been successfully implemented in stirred tank, airlift, biofilter and biotrickling filter reactors for the removal of hydrophobic VOCs and CH4 at unprecedentedly high removal rates. The high affinity of the non-aqueous phase for the target gas pollutant creates a new and efficient mass transfer pathway and increases process robustness compared to conventional biotechnologies. Finally, recent studies have shown that the use of hydrophobic biomass can boost the abatement performance of TPPBs by one order of magnitude

Stress-strain response and microstructural evolution of a FeMnCAl TWIP steel during tension-compression tests

© 2016. The stress-strain response of a Fe-17.5Mn-0.7C-2Al TWIP steel during cyclic loading has been investigated by means of tension-compression tests within the strain limits of ±2%, ±5% and ±10%. In addition, the microstructural evolution during the ±5% cyclic test has also been studied. The difference between the forward and reverse stress for each pre-strain has been analyzed at 0.2% offset strain and at the strains in which forward and reverse curves were parallel in order to study the Bauschinger effect (BE) and permanent softening, respectively. The evolution of the BE with pre-strain for this steel is similar to other FeMnC TWIP steels, that is, increasing values of BE are obtained as the pre-strain increases. However, its absolute values are half those reported in the literature on other FeMnC steels. This diminution of the BE is related to the lower activity of mechanical twinning in FeMnCAl TWIP steels at the pre-strains herein investigated, which promotes less polarized stresses in the matrix due to the lower dislocation storage capacity.Regarding permanent softening, the evolution is similar to that of the BE and the same analysis can be applied. During reverse compression, a slight increase of twin thickness and twin spacing with respect to the first tensile stage took place. This fact might be linked to the lower flow stress observed in the permanent softening period during reverse straining.Peer ReviewedPostprint (author's final draft