On the formal foundations of cash management systems

[EN] Cash management aims to find a balance between what is held in cash and what is allocated in other investments in exchange for a given return. Dealing with cash management systems with multiple accounts and different links between them is a complex task. Current cash management models provide analytic solutions without exploring the underlying structure of accounts and its main properties. There is a need for a formal definition of cash management systems. In this work, we introduce a formal approach to manage cash with multiple accounts based on graph theory. Our approach allows a formal reasoning on the relation between accounts in cash management systems. A critical part of this formal reasoning is the characterization of desirable and non-desirable cash management policies. Novel theoretical results guide cash managers in the analysis of complex cash management systems.This work is partially funded by projects Logistar (H2020-769142), AI4EU (H2020-825619) and 2017 SGR 172.Salas-Molina, F.; Rodriguez-Aguilar, JA.; Pla Santamaría, D.; Garcia-Bernabeu, A. (2021). On the formal foundations of cash management systems. Operational Research. 21(2):1081-1095. https://doi.org/10.1007/s12351-019-00464-6S10811095212Baccarin S (2009) Optimal impulse control for a multidimensional cash management system with generalized cost functions. Eur J Oper Res 196(1):198–206Bollobás B (2013) Modern graph theory, vol 184. Springer, BerlinBondy JA, Murty USR (1976) Graph theory with applications, vol 290. Macmillan, LondonChartrand G, Oellermann OR (1993) Applied and algorithmic graph theory, vol 993. McGraw-Hill, New YorkConstantinides GM, Richard SF (1978) Existence of optimal simple policies for discounted-cost inventory and cash management in continuous time. Oper Res 26(4):620–636da Costa Moraes MB, Nagano MS, Sobreiro VA (2015) Stochastic cash flow management models: a literature review since the 1980s. In: Guarnieri P (ed) Decision models in engineering and management. Springer, Berlin, pp 11–28de Avila Pacheco JV, Morabito R (2011) Application of network flow models for the cash management of an agribusiness company. Comput Ind Eng 61(3):848–857Golden B, Liberatore M, Lieberman C (1979) Models and solution techniques for cash flow management. Comput Oper Res 6(1):13–20Gormley FM, Meade N (2007) The utility of cash flow forecasts in the management of corporate cash balances. Eur J Oper Res 182(2):923–935Gregory G (1976) Cash flow models: a review. Omega 4(6):643–656Makridakis S, Wheelwright SC, Hyndman RJ (2008) Forecasting methods and applications. Wiley, New YorkRighetto GM, Morabito R, Alem D (2016) A robust optimization approach for cash flow management in stationery companies. Comput Ind Eng 99:137–152Salas-Molina F (2017) Risk-sensitive control of cash management systems. Oper Res. https://doi.org/10.1007/s12351-017-0371-0Salas-Molina F, Pla-Santamaria D, Rodriguez-Aguilar JA (2018) A multi-objective approach to the cash management problem. Ann Oper Res 267(1):515–529Srinivasan V, Kim YH (1986) Deterministic cash flow management: state of the art and research directions. Omega 14(2):145–166Valiente G (2013) Algorithms on trees and graphs. Springer, Berli

Morphology and characterisation of the relict facies on the internal continental shelf in the Gulf of Cadiz, between Ayamonte and Huelva (southern Iberian Peninsula)

The objectives of the present paper are the determination of the morphologic characteristics of the superficial Quaternary relict facies on the internal continental shelf in the Gulf of Cadiz, between Ayamonte and Huelva (southern Spain), their characterisation, and their evolution in the final phases of the last eustatic hemicycle. The study area extends from the mouth of the Guadiana River to the mouth of the Tinto-Odiel River, and from the 6 m isobath to the 56 m isobath. High-resolution seismic profiles (3.5 kHz and Geopulse, 175 J), sonographic profiles (SSS, 100 kHz), and bathymetric profiles (Echotrac sounder) were used in this study. Sediment samples were obtained using Van Veen and Shipek drags. Bathymetric, physiographic, lithologic and morphologic analyses were performed to determine the superficial sediment distribution, relict facies distribution, and thickness of the unconsolidated sediment cover. Analysis of the data obtained indicated that the relict facies beaches and coastal barriers associated with coastal spits located in the ancient outlets of the rivers. Relict facies were grouped into well-differentiated depths, indicating that their position on the continental shelf is influenced by the still-stands and the periods of rapid sea-level changes. The nature of the outcropping relict facies shows that their final configuration can be related to the shelf construction processes, as well as to the most important Holocene transgressive phases.Los objetivos de este trabajo son la determinación de las características morfológicas, la caracterización de las facies relictas cuaternarias superficiales y el estudio de su evolución con relación a las fases finales del último hemiciclo eustático en la plataforma continental interna del golfo de Cádiz, entre Ayamonte y Huelva. El área de estudio abarca desde la desembocadura del río Guadiana hasta la del río Tinto-Odiel y desde los 6 m hasta 56 m de profundidad. Se utilizó gran cantidad de material geofísico, en el que se encuentran perfiles sísmicos de alta resolución (3.5 kHz y Geopulse, 175 J), perfiles sonográficos y perfiles batimétricos, además de muestras de sedimentos obtenidas con dragas Van Veen y Shipek. Con esta información se han realizado análisis batimétricos, fisiográficos, litológicos y morfológicos, además de determinar la distribución de los sedimentos superficiales y de las facies relictas y de cuantificar la potencia de la cobertera sedimentaria. Con todos los datos obtenidos se ha determinado que las facies relictas son interpretadas como playas y cordones litorales asociados a flechas litorales situadas en las antiguas desembocaduras de los ríos. Las formas descritas están agrupadas en zonaciones batimétricas bien diferenciadas, lo que indica que su posición en la plataforma continental está influida por las paradas y etapas de movimiento rápido del nivel del mar. Las características de las facies relictas aflorantes indican que su configuración final puede estar relacionada con los procesos de edificación de la plataforma a partir de las mayores fases transgresivas holocenas.Instituto Español de Oceanografí

Late Quaternary multi-genetic processes and products on the northern Gulf of Cadiz upper continental slope (SW Iberian Peninsula)

On continental margins, the upper slope to shelf break environment forms a critical region where sediment supply, hydrographic activity and gravitational processes determine how and when sediments are partitioned between the shallow- and deep-marine realm. On the SW Iberian margin, relatively few studies have addressed the dynamics of this region, although it holds key information regarding the link between the sedimentary evolution of the continental shelf and the contourite depositional system on the middle slope. This work therefore presents a high-resolution analysis of the morphological and stratigraphic expressions of late Quaternary (dominantly last glacial and present-day interglacial) sedimentary processes on the upper slope and shelf margin sector between 7° and 7°30’ W. The integration of seismic, bathymetric and hydrographic data reveals the presence of alongslope processes and products (a bottom current-related plastered drift, moat, erosional surface and terrace, an internal wave-/tide-controlled sediment wave field), downslope (gravitational) processes and products (an upper slope – shelf margin valley system, slumps, debrites, gullies), neotectonic elements (diapirs) and fluid flow features (pockmarks, bright spots). The spatial distribution of these features indicates that the study area becomes increasingly alongslope-dominated towards the W, and oppositely, more downslope-dominated towards the E, because sediment supply to the latter area is enhanced under the dominant eastward dispersal of fluvially supplied sediments on the shelf. In addition, glacial-interglacial variations in the amount of sediments supplied to the shelf edge and the intensity of oceanographic processes in the study area also generate a distinct temporal variability, with glacial and interglacial intervals respectively recording principally downslope- and alongslope-controlled morphological elements. Finally, regardless of these overall spatial and temporal patterns, diapirism and fluid flow are inferred to locally destabilize sediments and induce small-scale mass wasting in the study area. These findings are not only relevant to the northern Gulf of Cadiz, but also to the general understanding of sedimentary dynamics and controls in mixed downslope- and alongslope-controlled upper slope to shelf margin settings worldwide.T. Mestdagh is funded through a doctoral scholarship of the Ghent University Special Research Fund (BOF). We would like to thank the captains, crews and scientists involved in research campaigns COMIC 2013 on board of RV Belgica and LASEA 2013 on board of RV Ramón Margalef. Ship time on RV Belgica was provided by BELSPO and RBINS-OD Nature. This research was performed in collaboration with ”The Drifters” Research Group of the Royal Holloway University of London (UK), and is associated to projects CTM 2012-39599-C03 , CGL2016-80445-R ‘SCORE’ ( AEI/FEDER , UE), CTM2016-75129-C3-1-R , CGL2011-30302-C02-02 and CTM2017-88237-P . Editor Michele Rebesco and two anonymous reviewers are kindly acknowledged for providing constructive feedback

Multiscale Characterization of Nanoengineered Fiber-Reinforced Composites: Effect of Carbon Nanotubes on the Out-of-Plane Mechanical Behavior

The mechanical properties of the matrix and the fiber/matrix interface have a relevant influence over the mechanical properties of a composite. In this work, a glass fiber-reinforced composite is manufactured using a carbon nanotubes (CNTs) doped epoxy matrix. The influence of the CNTs on the material mechanical behavior is evaluated on the resin, on the fiber/matrix interface, and on the composite. On resin, the incorporation of CNTs increased the hardness by 6% and decreased the fracture toughness by 17%. On the fiber/matrix interface, the interfacial shear strength (IFSS) increased by 22% for the nanoengineered composite (nFRC). The influence of the CNTs on the composite behavior was evaluated by through-thickness compression, short beam flexural, and intraply fracture tests. The compressive strength increased by 6% for the nFRC, attributed to the rise of the matrix hardness and the fiber/matrix IFSS. In contrast, the interlaminar shear strength (ILSS) obtained from the short beam tests was reduced by 8% for the nFRC; this is attributed to the detriment of the matrix fracture toughness. The intraply fracture test showed no significant influence of the CNTs on the fracture energy; however, the failure mode changed from brittle to ductile in the presence of the CNTs

Two highly divergent alcohol dehydrogenases of melon exhibit fruit ripening-specific expression and distinct biochemical characteristics

Alcohol dehydrogenases (ADH) participate in the biosynthetic pathway of aroma volatiles in fruit by interconverting aldehydes to alcohols and providing substrates for the formation of esters. Two highly divergent ADH genes (15% identity at the amino acid level) of Cantaloupe Charentais melon (Cucumis melo var. Cantalupensis) have been isolated. Cm-ADH1 belongs to the medium-chain zinc-binding type of ADHs and is highly similar to all ADH genes expressed in fruit isolated so far. Cm-ADH2 belongs to the short-chain type of ADHs. The two encoded proteins are enzymatically active upon expression in yeast. Cm-ADH1 has strong preference for NAPDH as a co-factor, whereas Cm-ADH2 preferentially uses NADH. Both Cm-ADH proteins are much more active as reductases with Kms 10–20 times lower for the conversion of aldehydes to alcohols than for the dehydrogenation of alcohols to aldehydes. They both show strong preference for aliphatic aldehydes but Cm-ADH1 is capable of reducing branched aldehydes such as 3-methylbutyraldehyde, whereas Cm-ADH2 cannot. Both Cm-ADH genes are expressed specifically in fruit and up-regulated during ripening. Gene expression as well as total ADH activity are strongly inhibited in antisense ACC oxidase melons and in melon fruit treated with the ethylene antagonist 1-methylcyclopropene (1-MCP), indicating a positive regulation by ethylene. These data suggest that each of the Cm-ADH protein plays a specific role in the regulation of aroma biosynthesis in melon fruit

Recorrido Itinerario Sevilla-Mérida. La rubefacción en suelos de Sierra Morena y Extremadura. Rubefacción sobre materiales ácidos

25 páginas.-- 4 tablas.-- 4 perfiles de suelos.--- Guía científica: Excursión Sevilla-Salamanca..-- Actas del XII Congreso Latinoamericano de la Ciencia del Suelo. Salamanca, Sevilla (ESPAÑA), 19 a 23 de septiembre de 1993.La catena de suelos de LOS LAGOS DEL SERRANO se encuentra en plena Sierra Morena, en la provincia de Sevilla, término municipal de El Ronquillo, en el área de la urbanización denominada "LAGOS DEL SERRANO" Se ubica en la hoja topográfica nº 948 “Castilblanco de los Arroyos", cerca del embalse de CALA. El relieve de esta zona va de colinado a abrupto de tipo estructural, muy bien definidoy perfectamente alineado según las direcciones de los pliegues, fruto de la intensa orogénia hertzinica que plegó y remodeló los materialesdepositados y sedimentados durante el Paleozóico.Peer reviewe

Puberty in the Bronze Age: First application of a puberty estimation method to a prehistoric population

This is the peer reviewed version of the following article: Doe, Danielle M., et al. "Puberty in the Bronze Age: First application of a puberty estimation method to a prehistoric population". International Journal of Osteoarchaeology 29.6 (2019): 1091-1099, which has been published in final form at https://doi.org/10.1002/oa.2822. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived VersionsPuberty and adolescence represent a significant period of physical growth and maturation and a critical life stage in which children transition into adults within their societies. Numerous studies have observed a secular trend and have determined that puberty is now occurring earlier than in the past. This investigation represents the first application of a methodology for assessing the pubertal status of osteological remains to a prehistoric skeletal sample. Six Bronze Age adolescent skeletons from the Cerro de La Encantada archaeological site (Ciudad Real, Spain) were analysed. Prepubescence was observed at age 9 and the transition phase of the pubertal growth spurt at 15 years of age. These results were similar to those obtained from medieval, Industrial Revolution, and modern populations, both within and outside of the Iberian Peninsula. The similarity in the development of the Bronze Age adolescents to that of other past and contemporary populations suggests that the pubertal process has remained essentially unchanged across millennia until recent times. However, other interpretations, including the influence of a subpar developmental environment and potential methodological artefacts, are possible. Nevertheless, studies of this type provide important information about a crucial transitory period in human developmentThe Laboratorio de Poblaciones del Pasado (LAPP) has been supported by Projects HAR2016‐78036‐P, HAR2016‐74846‐P, HAR2017‐82755‐P, and HAR2017‐83004‐P (Spanish Government) and a grant (Ref. 38360) from the Leakey Foundatio

Comparison of body mass index (BMI) with the CUN-BAE body adiposity estimator in the prediction of hypertension and type 2 diabetes

Background Obesity is a world-wide epidemic whose prevalence is underestimated by BMI measurements, but CUN-BAE (Clínica Universidad de Navarra - Body Adiposity Estimator) estimates the percentage of body fat (BF) while incorporating information on sex and age, thus giving a better match. Our aim is to compare the BMI and CUN-BAE in determining the population attributable fraction (AFp) for obesity as a cause of chronic diseases. Methods We calculated the Pearson correlation coefficient between BMI and CUN-BAE, the Kappa index and the internal validity of the BMI. The risks of arterial hypertension (AHT) and diabetes mellitus (DM) and the AFp for obesity were assessed using both the BMI and CUN-BAE. Results 3888 white subjects were investigated. The overall correlation between BMI and CUN-BAE was R2 = 0.48, which improved when sex and age were taken into account (R2 > 0.90). The Kappa coefficient for diagnosis of obesity was low (28.7 %). The AFp was 50 % higher for DM and double for AHT when CUN-BAE was used. Conclusions The overall correlation between BMI and CUN-BAE was not good. The AFp of obesity for AHT and DM may be underestimated if assessed using the BMI, as may the prevalence of obesity when estimated from the percentage of BF