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sIMPLE COMPUTING OF THE CUsTOMER LIFETIME VALUE:A FIXED LOCAL-OPTIMAL POLICY APPROACH

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Journal of systems science and systems Engineering 2014年第4期23卷 439-459页

作者： julio B.Clempner Alexander s.Poznyak Center for Economics Management and Social Research Department of Control Automatics Center for Research and Advanced studies

In this paper,we present a new method for finding a fixed local-optimal policy for computing the customer lifetime *** method is developed for a class of ergodic controllable finite Markov *** propose an approach based on a non-converging state-value function that fluctuates（increases and decreases） between states of the dynamic *** prove that it is possible to represent that function in a recursive format using a one-step-ahead fixed-optimal ***,we provide an analytical formula for the numerical realization of the fixed local-optimal *** also present a second approach based on linear programming,to solve the same problem,that implement the c-variable method for making the problem computationally *** the end,we show that these two approaches are related：after a finite number of iterations our proposed approach converges to same result as the linear programming *** also present a non-traditional approach for ergodicity *** validity of the proposed methods is successfully demonstrated theoretically and,by simulated credit-card marketing experiments computing the customer lifetime value for both an optimization and a game theory approach.

关键词： Customer lifetime value optimization optimal policy method linear programming ergodic controllable Markov chains asynchronous games

Interpenetrating polymers supported on microporous polypropylene membranes for the transport of chromium ions

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Chinese Journal of Chemical Engineering 2017年第7期25卷 938-946页

作者： Yesid Tapiero julio sánc.ez BernabéL.Rivas Polymer Department Faculty of ChemistryUniversity of ConcepdonCasilla 160-C ConcepcionChile

Modifying polypropylene membranes with interpenetrating polymer networks(IPNs) through the incorporation of poly(glycidyl methacrylate-N-methyl-D-glucamine)(P(GMA-NMG)) was performed by in situ synthesis via radical polymerization. The surface of the polypropylene membrane was activated by hydrophilic grafted polyelectrolyte, and then, pressure injection was used for the impregnation of the reactive solution in the *** types of pore-filled membranes were synthesized, chelating interpenetrating homopolymer networks of P(GMA-NMG), and chelating-ion exchange interpenetrating polymer networks(e.g., P(GMA-NMG)/P(AA),P(GMA-NMG)/P(AMPsA), and P(GMA-NMG)/P(Cl VBTA)). After their synthesis, the modified polypropylene membranes were characterized using techniques such as the electrokinetic potential, sEM, FT-IR, and Donnan dialysis to corroborate the chromium ion transport. The P(GMA-NMG) and complex network membranes exhibited a hydrophilic character with a water-uptake capacity between 20% and 35% and a percentage of modification between 4.0% and 7.0% in comparison with the behavior of the unmodified polypropylene *** chromium ions were efficiently transported from the food chamber at p H 9.0 when the 65.2%MTA1 P(Cl VBTA) homopolymer IPN membrane and 48.5% MTAG P(GMA-NMG)/P(Cl VBTA) IPN membrane were used. similarly, hexavalent chromium ions were removed from the food chamber at pH 3.0 when MTAG(63.30%) and MTA1(35.68%) were used in 1 mol·L^(-1)Na Cl solution as the extraction reagent.

关键词： Polypropylene N-methyI-D-glucamine Ion exchange Donnan dialysis Interpenetrating polymer networks Chromium

Acute necrotizing pancreatitis: surgical indications and technical procedures

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World Journal of Clinical Cases 2014年第12期2卷 840-845页

作者： José Manuel Aranda-Narváez Antonio Jesús González-sánc.ez María Custodia Montiel-Casado Alberto Titos-García julio santoyo-santoyo General Digestive and Transplantation Surgery Department University Regional Hospital 29010 Málaga Spain

Necrosis of pancreatic parenchyma or extrapancreatic tissues is present in 10%-20% of patients with acute pancreatitis, defining the necrotizing presentation frequently associated with high morbidity and mortality rates. During the initial phase of acute necrotizing pancreatitis the most important pillars of medical treatment are fluid resuscitation, early enteral nutrition, endoscopic retrograde colangiopancreatography if associated cholangitis and intensive care unit support. When infection of pancreatic or extrapancreatic necrosis occurs, surgical approach constitutes the most accepted therapeutic option. In this context, we have recently assited to changes in time for surgery(delaying the indication if possible to around 4 wk to deal with "walledoff" necrosis) and type of access for necrosectomy: from a classical open approach(with closure over large-bore drains for continued postoperative lavage or semiopen techniques with scheduled relaparotomies), trends have changed to a "step-up" philosophy with initial percutaneous drainage and posterior minimally invasive or endoscopic access to the retroperitoneal cavity for necrosectomy if no improvement has been previously achieved. These approaches are progressively gaining popularity and morbidity and mortality rates have decreased significantly. Therefore, a staged, multidisciplinary, step-up approach with minimally invasive or endoscopic access for necrosectomy is widely accepted nowadays for management of pancreatic necrosis.

关键词： Acute pancreatitis Necrotizing pancreatitis surgery Open necrosectomy Minimal access retroperitoneal pancreatic necrosectomy Video-assisted retroperitoneal debridement

Photosynthetic Gas Exchange and Nitrogen Assimilation in Green Bean Plants supplied with Two sources of silicon

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 963-980页

作者： julio C.Anchondo-Páez Esteban sánc.ez Carlos A.Ramírez-Estrada Alondra salcido-Martínez Erick H.Ochoa-Chaparro Department of Plant Physiology Centro de Investigación en Alimentación y DesarrolloCiudad Delicias33089México

Beans contain a wide range of vitamins,proteins,calcium,and zinc which make them an important food source for many *** meet the demand for bean production worldwide,large amounts of fertilizers and pesticides are ***,the cost of production and environmental impact *** produce food sustainably,the use of beneficial nutrients such as silicon as a biostimulant has been ***,information about the effect of different sources of silicon on the metabolism of bean plants is *** plants *** were grown in pots for 60 days and the effect of foliar application of silicon nanoparticles and the silicon-based biostimulant Codasilat 4 concentrations(0,1,2,and 4 mM)on total biomass,yield,photosynthetic pigment concentration,photosynthetic activity,stomatal conductance,transpiration rate,chlorophyll fluorescence,and nitrogen assimilation were *** results obtained showed that the supply of silicon at a dose of 1 mM functioned as a biostimulant,favoring gas exchange and nitrogen assimilation within the plant,which stimulated growth and *** results of this research work allowed a better comprehension of the effects of silicon application through silicon nanoparticles and the biostimulant Codasilon the physiology of green bean plants.

关键词： Nanoparticles silicon Phaseolus vulgaris L.

Cardiorespiratory fitness measured with cardiopulmonary exercise testing and mortality in patients with cardiovascular disease:A systematic review and meta-analysis

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Journal of sport and Health science 2021年第6期10卷 609-619,F0003页

作者： Yasmin ezzatvar MikelIzquierdo julio Núñez Joaquín Calatayud Robinson Ramírez-Vélez Antonio García-Hermoso Exercise Intervention for Health Research Group(EXINH-RG) Department of PhysiotherapyUniversitat de ValènciaValencia 46010Spain Navarrabiomed Navarra Hospital Complex(CHN)Public University of Navarra(UPNA)Navarra Medical Research Institute(IdiSNA)Pamplona 31008Spain CIBER of Frailty and Healthy Aging(CIBERFEs) Instituto de Salud Carlos IIIMadrid 28029Spain Department of Cardiology Valencia University HospitalBiomedical Research Institute(INCLIVA)Valencia 46010Spain CIBER in Cardiovascular Diseases(CIBERCV) Madrid 28029Spain sciences of Physical Activity Sports and Health SchoolUniversity of Santiago of Chile(USACH)Santiago 71783-5Chile

Background Cardiorespiratory fitness(CRF)is inversely associated with mortality in apparently healthy subjects and in some clinical populations,but evidence for the association between CRF and all-cause and/or cardiovascular disease(CVD)mortality in patients with established CVD is *** study aimed to quantify this *** We searched for prospective cohort studies that measured CRF with cardiopulmonary exercise testing in patients with CVD and that examined all-cause and CVD mortality with at least 6 months of *** hazard ratios(HRs)were calculated using random-effect inverse-variance *** Data were obtained from 21 studies and included 159,352 patients diagnosed with CVD(38.1%female).Pooled HRs for all-cause and CVD mortality comparing the highest *** category of CRF were 0.42(95%confidence interval(95%CI):0.28–0.61)and 0.27(95%CI:0.16–0.48),*** HRs per 1 metabolic equivalent(1-MET)increment were significant for all-cause mortality(HR=0.81;95%CI:0.74–0.88)but not for CVD mortality(HR=0.75;95%CI:0.48–1.18).Coronary artery disease patients with high CRF had a lower risk of all-cause mortality(HR=0.32;95%CI:0.26–0.41)than did their unfit *** 1-MET increase was associated with lower all-cause mortality risk among coronary artery disease patients(HR=0.83;95%CI:0.76–0.91)but not lower among those with heart failure(HR=0.69;95%CI:0.36–1.32).Conclusion A better CRF was associated with lower risk of all-cause mortality and *** study supports the use of CRF as a powerful predictor of mortality in this population.

关键词： Cardiopulmonary fitness Coronary artery disease Exercise capacity Heart failure survival

Affinity-Based Network Interfaces for Efficient Communication on Multicore Architectures

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Journal of Computer science & Technology 2013年第3期28卷 508-524页

作者： Andrés Ortiz julio Ortega Antonio F.Díaz Alberto Prieto Department of Communications Engineering University of Málaga Department of Computer Architecture and Technology/CITIC University of Granada

Improving the network interface performance is needed by the demand of applications with high communication requirements （for example, some multimedia, real-time, and high-performance computing applications）, and the availability of network links providing multiple gigabits per second bandwidths that could require many processor cycles for communication tasks. Multicore architectures, the current trend in the microprocessor development to cope with the difficulties to further increase clock frequencies and microarchitecture efficiencies, provide new opportunities to exploit the parallelism available in the nodes for designing efficient communication architectures. Nevertheless, although present Os network stacks include multiple threads that make it possible to execute network tasks concurrently in the kernel, the implementations of packet-based or connection-based parallelism are not trivial as they have to take into account issues related with the cost of synchronization in the access to shared resources and the efficient use of caches. Therefore, a common trend in many recent researches on this topic is to assign network interrupts and the corresponding protocol and network application processing to the same core, as with this affinity scheduling it would be possible to reduce the contention for shared resources and the cache misses. In this paper we propose and analyze several configurations to distribute the network interface among the different cores available in the server. These alternatives have been devised according to the affinity of the corresponding communication tasks with the location （proximity to the memories where the different data structures are stored） and characteristics of the processing core. As this approach uses several cores to accelerate the communication path of a given connection, it can be seen as complementary to those that consider several cores to simultaneously process packets belonging to either the same or different connections.

关键词： interrupt affinity processor affinity network interface offioading, sIMICs

Electrochemical reduction of Cr(Ⅵ)in the presence of sodium alginate and its application in water purification

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Journal of Environmental sciences 2021年第3期33卷 304-312页

作者： Bryan Butter Paola santander Guadalupe del CPizarro Diego POyarzún Federico Tasca julio sánc.ez Facultad de Química y Biología Universidad de Santiago de ChileUSACHCasilla 40Correo 33SantiagoChile Departamento de Química Universidad Tecnológica MetropolitanaJ.P.Alessandri 1242SantiagoChile Laboratorio de Nanotecnología Recursos Naturales y Sistemas ComplejosFacultad de Ciencias NaturalesUniversidad de AtacamaCopayapu 485CopiapóChile

Chromium(Cr)is used in many manufacturing processes,and its release into natural waters is a major environmental problem *** concentrations of Cr(Ⅵ)are toxic to human health and living organisms due to the carcinogenic and mutagenic nature of this *** work examined the conversion of Cr(Ⅵ)to Cr(Ⅲ)via electrochemical reduction using gold electrode in an acidic sodium alginate(sA)solution and subsequent removal of the produced Cr(Ⅲ)-sA by the polymer-enhanced ultrafiltration(PEUF)technique.A solution of sA in nitric acid was used both as an electrolytic medium during the voltammetric measurements and bulk electrolysis and as an extracting agent during the PEUF *** electroanalysis of Cr(Ⅵ)was performed by linear sweep voltammetry in the presence of acidic sA solution to study its voltammetric behavior as a function of the Cr(Ⅵ)concentration,pH,presence of Cr(Ⅲ),sA concentration and scan *** addition,the quantitative reduction of Cr(Ⅵ)to Cr(Ⅲ)was studied through the bulk electrolysis *** results showed efficient reduction with well-defined peaks at approximately 0.3 V ***/AgCl,using a gold working *** the pH increased,the reduction signal strongly decreased until its *** optimum sA concentration was 10 mmol/L,and it was observed that the presence of Cr(Ⅲ)did not interfere in the Cr(Ⅵ)*** the quantitative reduction by bulk electrolysis in the presence of acidic sA solution,it was possible to reduce all Cr(Ⅵ)to Cr(Ⅲ)followed by its removal via PEUF.

关键词： Alginate solution Chromium Electroanalytical chemistry Ultrafiltration Water purification

Long Coronary Lesions: Challenging Cases for Percutaneous Coronary Intervention

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International Journal of Clinical Medicine 2016年第1期7卷 89-93页

作者： julio Núñez Gema Miñana Juan sanchis Department of Cardiology Hospital Clínico Universitario Valencia Spain

Long coronary lesions are associated with adverse outcomes after percutaneous coronary intervention since the era of plain balloon angioplasty. Long lesion and long stent length are considered as important predictors of restenosis after percutaneous coronary intervention. With the advent of newer generation drug eluting stents, there has been dramatic reduction in the rates of restenosis and repeat revascularization, even in complex cohort of patients with long coronary lesions. We report one such case of long coronary lesion which was intervened successfully with newer generation, thin strut, biodegradable polymer coated sirolimus-eluting stents.

关键词： Drug Eluting stents Biodegradable Polymer Percutaneous Coronary Intervention Treatment Outcome

Prefoldins 3 and 5 Play an Essential Role in Arabidopsis Tolerance to salt stress

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Molecular Plant 2009年第3期2卷 526-534页

作者： Miguel A. Rodriguez-Milla julio salinas Departamento de Biologfa de Plantas Centro de Investigaciones Biologicas-CSIC Ramiro de Maeztu 9 28040 Madrid Spain

During the last years, our understanding of the mechanisms that control plant response to salt stress has been steadily progressing. Pharmacological studies have allowed the suggestion that the cytoskeleton may be involved in regulating such a response. Nevertheless, genetic evidence establishing that the cytoskeleton has a role in plant tolerance to salt stress has not been reported yet. Here, we have characterized Arabidopsis T-DNA mutants for genes encoding proteins orthologous to prefoldin （PFD） subunits 3 and 5 from yeast and mammals. In these organisms, PFD subunits, also known as Genes Involved in Microtubule biogenesis （GIM）, form a heterohexameric PFD complex implicated in tubulin and actin folding. We show that, indeed, PFD3 and PFD5 can substitute for the loss of their yeast orthologs, as they are able to complement yeast gim2Δ and gim5Δ mutants, respectively. Our results indicate that pfd3 and pfd5 mutants have reduced levels of α- and β-tubulin compared to the wild-type plants when growing under both control and salt-stress conditions. In addition, pfd3 and pfd5 mutants display alterations in their developmental patterns and microtubule organization, and, more importantly, are hypersensitive to high concentrations of NaCl but not of LiCl or mannitol. These results demonstrate that the cytoskeleton plays an essential role in plant tolerance to salt stress.

关键词： Prefoldins cytoskeleton tubulin actin microtubule salt tolerance Arabidopsis