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Papers by Lisandro Ramos

CardioMetabolic Syndrome Journal

Cardiovascular disease (CVD) is the leading cause of mortality worldwide. CVD is primarily driven... more Cardiovascular disease (CVD) is the leading cause of mortality worldwide. CVD is primarily driven by modifiable risk factors, including physical inactivity, smoking, high fat and high salt diets resulting in hypertension and obesity. Amongst these modifiable risk factors, obesity has taken a central role in CVD development. Adipose tissue acts not only as a reservoir of fat, but as an endocrine organ, releasing a number of biologically active "adipokines" that can regulate metabolic homeostasis. Given the intricate relationship between obesity and CVD, is imperative to understand the signals by which adipose tissue influences cardiovascular physiology and disease. Indeed, many adipose tissue-derived molecules have the potential to act as biomarkers for diagnosis, prognosis and even therapeutic targets in CVD. In this review, we discuss the impact of adipose-derived molecules in the pathogenesis of several CVD etiologies, including ischemic heart disease and heart failure.

Small Peptide, Large Implications: Endotrophin in Heart Failure with Preserved Ejection Fraction

Clinical Chemistry

Sociedades Rurales, Producción y Medio Ambiente, 2014

Resumen. El presente estudio es un análisis exhaustivo de los elementos científicos y técnicos so... more Resumen. El presente estudio es un análisis exhaustivo de los elementos científicos y técnicos sobre la gluconeogénesis hepática en los bovinos lecheros, donde factores como las adaptaciones de las papilas ruminales, el metabolismo de la glucosa, la oxidación y β-oxidación de lípidos, y la formación y uso de cuerpos cetónicos son componentes esenciales en los ajustes metabólicos dentro de la producción láctea. Esta revisión hace mayor énfasis en la estructura de modelos esquemáticos de integración bioquímica, especialmente durante el balance energético negativo con el fin de alcanzar un adecuado equilibrio entre el consumo de energía, por parte del animal, y la energía requerida para el mantenimiento y la preñez (en la vaca gestante) y el mantenimiento y la lactancia (en la vaca lactante). Por lo tanto, la información revisada pretende hacer más accesible la comprensión de los procesos bioquímicos que ocurren antes y después del parto, así como la fisiología y bioquímica de la lactancia temprana, eventos de vital importancia para la salud, producción y rentabilidad en bovinos lecheros.

Sociedades Rurales, Producción y Medio Ambiente, 2014

Resumen. En este estudio se presentan elementos científicos y técnicos sobre el periodo de transi... more Resumen. En este estudio se presentan elementos científicos y técnicos sobre el periodo de transición de la vaca lechera, en el cual factores como la modificación de las poblaciones microbianas en el rumen, el metabolismo hepático y la recuperación, tanto de las paredes ruminales como de la glándula mamaria, son componentes esenciales en las adaptaciones previas a la lactancia. La revisión hace hincapié en la necesidad de un manejo nutricional especial durante el balance energético negativo (ben) con el fin de alcanzar un adecuado equilibrio entre el consumo de energía, por parte del animal, y la energía requerida para el mantenimiento y la preñez (en la vaca gestante), y el mantenimiento y la lactancia (en la vaca lactante). Por lo tanto, la información revisada permitirá difundir de manera más concisa los conocimientos relacionados con el entendimiento del metabolismo energético. La compilación de estudios publicados también pretende hacer más accesible la comprensión de los eventos bioquímicos y endocrinos que ocurren alrededor del parto, fisiología y bioquímica del periodo seco y el posparto temprano, eventos de vital importancia para la salud, la producción y la rentabilidad de las vacas lecheras.

Actualidad Económica, 2021

This article aims to characterize the Software and Computer Services Sector from the point of vie... more This article aims to characterize the Software and Computer Services Sector from the point of view of the contribution it makes to local development, with special emphasis on the possible consequences for the problem of work rotation in the case of Tandil. For the study, a review of the literature, analysis of national reports, interviews with key actors and compilation of data on companies in the sector were developed. Among the main results it found is a tension between the incorporation of personnel to increase sales to the foreign market and the expansion of exports to favor the incorporation of human resources, without pressure to lower wages.

The role of enhanced cardiac fibroblast glycosylation products on collagen synthesis

The FASEB Journal, 2012

Author(s): Maya-Ramos, Lisandro | Advisor(s): Kornberg, Thomas B | Abstract: Bilaterality, is the... more Author(s): Maya-Ramos, Lisandro | Advisor(s): Kornberg, Thomas B | Abstract: Bilaterality, is the predominant body plan in the animal kingdom. Cells either from the left or right side, rarely cross the body midline plane throughout life, as evidenced by naturally occurring bilateral gynandromorphs. However, it has been a longstanding mystery how this evolutionary conserved ipsilaterality is achieved in bilaterians, including humans. Using the chick embryo as a model, we show that extracellular matrix (ECM) and caspase-3-dependent programmed cell death (PCD) localize to the primitive streak (PS) midline. Both, faithfully direct ipsilateral ingression through the inhibition of contralateral cellular invasion. PS midline PCD is dependent on ECM accumulation. Suppression of these components results in contralateral cellular invasion. Remarkably, induced PCD alone, without ECM, is sufficient to rescue ipsilateral gastrulation. Our findings reveal that PCD actively patterns ipsilaterality...

Programmed cell death along the midline axis patterns ipsilaterality in gastrulation

Science, 2020

Apoptosis prevents left-right crossing Animals generally display a bilateral body plan, with symm... more Apoptosis prevents left-right crossing Animals generally display a bilateral body plan, with symmetry between the left and right sides. Maya-Ramos and Mikawa examined the mechanism that prevents the crossing of cells between sides. Using chick embryos, they show that cellular mixing between sides is prevented by a barrier at the embryonic midline that involves programmed cell death and the extracellular matrix. This work demonstrates the dependence of normal development on programmed cell death during the gastrulation stage. Science , this issue p. 197

Revista de Ciências Agrárias, 2018

Na busca de alternativas para o controle de fitonematoides, vem sendo estudado o efeito nematicid... more Na busca de alternativas para o controle de fitonematoides, vem sendo estudado o efeito nematicida de metabolitos secundários ou resíduos vegetais. Dessa forma, a manipueira, resíduo líquido da industrialização da mandioca (Manihot esculenta), tem como composição glicosídeos cianogênicos com propriedades antimicrobianas. Objetivou-se avaliar o potencial da manipueira aplicada no solo, visando o controle de Meloidogyne javanica na cultura da soja. A manipueira foi aplicada nas concentrações de 0, 10, 20, 30, 40, 50, 60, 70, 80, 90 e 100%. O delineamento experimental foi inteiramente casualizado, em arranjo fatorial 11 × 2 (concentrações de manipueira × formas de aplicação-única e parcelada), com cinco repetições. As plantas de soja foram inoculadas com 3000 ovos e J2 de M. javanica por vaso. Sessenta dias após a primeira aplicação da manipueira, foram avaliadas características agronômicas e de parasitismo. A aplicação única da manipueira promoveu maior crescimento e desenvolvimento radicular, bem como redução do número de ovos e J2 na raiz e do fator de reprodução de M. javanica, para todas as concentrações. A aplicação parcelada teve maior efeito na redução do número de galhas e massas de ovos. As concentrações letais de manipueira para 50% da população de nematoides no solo e na raiz foram de 37,90% e 29,67%, respetivamente.

Pesquisa Agropecuária Tropical, 2016

Manipueira, a liquid residue obtained from the cassava industrialization, shows high toxicity to ... more Manipueira, a liquid residue obtained from the cassava industrialization, shows high toxicity to the microbial diversity. This study aimed at evaluating the potential of manipueira applied to the soil to control Meloidogyne incognita in soybean. A completely randomized design, in a 2 x 11 factorial scheme, was used, consisting of two application forms of manipueira (single and two applications), in eleven concentrations (0 %, 10 %, 20 %, 30 %, 40 %, 50 %, 60 %, 70 %, 80 %, 90 % and 100 %), with five replications per treatment. Some agronomic traits and parasitism characteristics were also evaluated. The plants that received a single application of manipueira showed a gain of 100.41 % in root length, while the volume and fresh root mass showed gains of 81.52 % and 28.11 %, respectively, with the two applications. Regarding parasitism, the single application was more effective in reducing the number of juveniles in the soil and roots, where the concentrations of manipueira to kill 50 ...

Comunicata Scientiae, 2017

To obtain high seed quality, good fertilization practices are essential due to its influence not ... more To obtain high seed quality, good fertilization practices are essential due to its influence not only on seed yield and weight, but also controlling the development of seedlings anomalies. Therefore, the aim of this study was to evaluate the effects of different forms of fertilization on yield and physiological quality of upland rice seeds. It was used nitrogen fertilization in coverage as urea and foliar fertilization with macro and micronutrients. The treatments consist of various sources and forms of fertilization, in a randomized block design, as follows: covering at tillering with N at 34 kg ha-1; covering at floral primordium with N at 34 kg ha-1; foliar fertilization at tillering; foliar fertilization in floral primordium; covering with N at 34 kg ha-1 in tillering and foliar fertilization in floral primordium; only basic fertilization and treatment without fertilization. The results showed that the application of nitrogen fertilizer with urea, at tillering and floral primord...

Childhood Trauma in U.S.-Mexico Border Area Mental Health and Primary Care Clinics

PsycEXTRA Dataset

Journal of Developmental Biology, 2013

The proepicardium is a transient extracardiac embryonic tissue that gives rise to the epicardium ... more The proepicardium is a transient extracardiac embryonic tissue that gives rise to the epicardium and a number of coronary vascular cell lineages. This important extracardiac tissue develops through multiple steps of inductive events, from specification of multiple cell lineages to morphogenesis. This article will review our current understanding of inductive events involved in patterning of the proepicardium precursor field, specification of cell types within the proepicardium and their extension and attachment to the heart.

American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, 2012

We examined the role that enzymatic protein O-GlcNAcylation plays in the development of diabetic ... more We examined the role that enzymatic protein O-GlcNAcylation plays in the development of diabetic cardiomyopathy in a mouse model of Type 2 diabetes mellitus (DM2). Mice injected with low-dose streptozotocin and fed a high-fat diet developed mild hyperglycemia and obesity consistent with DM2. Studies were performed from 1 to 6 mo after initiating the DM2 protocol. After 1 mo, DM2 mice showed increased body weight, impaired fasting blood glucose, and hyperinsulinemia. Echocardiographic evaluation revealed left ventricular diastolic dysfunction by 2 mo and O-GlcNAcylation of several cardiac proteins and of nuclear transcription factor Sp1. By 4 mo, systolic dysfunction was observed and sarcoplasmic reticulum Ca2+ ATPase expression decreased by 50%. Fibrosis was not observed at any timepoint in DM2 mice. Levels of the rate-limiting enzyme of the hexosamine biosynthetic pathway, glutamine:fructose-6-phosphate amidotransferase (GFAT) were increased as early as 2 mo. Fatty acids, which are...

American Journal of Physiology-Cell Physiology, 2014

Excess enzyme-mediated protein O-GlcNAcylation is known to occur with diabetes mellitus. A charac... more Excess enzyme-mediated protein O-GlcNAcylation is known to occur with diabetes mellitus. A characteristic of diabetic cardiomyopathy is the development of myocardial fibrosis. The role that enhanced protein O-GlcNAcylation plays in modulating the phenotype of cardiac fibroblasts (CF) is unknown. To address this issue, rat CF were cultured in normal glucose (NG; 5 mM glucose) or high-glucose (HG; 25 mM) media for 48 h. Results demonstrate that CF cultured in HG have higher levels (∼50%) of overall protein O-GlcNAcylation vs. NG cells. Key regulators of collagen synthesis such as transforming-growth factor-β1 (TGF-β1), SMADs 2/3, and SMAD 7 protein levels, including those of arginase I and II, were altered, leading to increases in collagen levels. The nuclear transcription factor Sp1 and arginase II evidence excess O-GlcNAcylation in HG cells. Expression in CF of an adenovirus coding for the enzyme N-acetylglucosaminidase, which removes O-GlcNAc moieties from proteins, decreased Sp1 a...

Implementação de um sistema FDMA. Análise de desempenho na presença de ruído e não-linearidade

The work reported in this paper deals with the impact of a nonlinear channel with noise in a FDMA... more The work reported in this paper deals with the impact of a nonlinear channel with noise in a FDMA system. The system is simulated using a time domain simulator, based on simulink. Five GSM channels are combined and then traverse a nonlinear noisy channel. Finally some results are discussed..

CardioMetabolic Syndrome Journal

Cardiovascular disease (CVD) is the leading cause of mortality worldwide. CVD is primarily driven... more Cardiovascular disease (CVD) is the leading cause of mortality worldwide. CVD is primarily driven by modifiable risk factors, including physical inactivity, smoking, high fat and high salt diets resulting in hypertension and obesity. Amongst these modifiable risk factors, obesity has taken a central role in CVD development. Adipose tissue acts not only as a reservoir of fat, but as an endocrine organ, releasing a number of biologically active "adipokines" that can regulate metabolic homeostasis. Given the intricate relationship between obesity and CVD, is imperative to understand the signals by which adipose tissue influences cardiovascular physiology and disease. Indeed, many adipose tissue-derived molecules have the potential to act as biomarkers for diagnosis, prognosis and even therapeutic targets in CVD. In this review, we discuss the impact of adipose-derived molecules in the pathogenesis of several CVD etiologies, including ischemic heart disease and heart failure.

Small Peptide, Large Implications: Endotrophin in Heart Failure with Preserved Ejection Fraction

Clinical Chemistry

Sociedades Rurales, Producción y Medio Ambiente, 2014

Resumen. El presente estudio es un análisis exhaustivo de los elementos científicos y técnicos so... more Resumen. El presente estudio es un análisis exhaustivo de los elementos científicos y técnicos sobre la gluconeogénesis hepática en los bovinos lecheros, donde factores como las adaptaciones de las papilas ruminales, el metabolismo de la glucosa, la oxidación y β-oxidación de lípidos, y la formación y uso de cuerpos cetónicos son componentes esenciales en los ajustes metabólicos dentro de la producción láctea. Esta revisión hace mayor énfasis en la estructura de modelos esquemáticos de integración bioquímica, especialmente durante el balance energético negativo con el fin de alcanzar un adecuado equilibrio entre el consumo de energía, por parte del animal, y la energía requerida para el mantenimiento y la preñez (en la vaca gestante) y el mantenimiento y la lactancia (en la vaca lactante). Por lo tanto, la información revisada pretende hacer más accesible la comprensión de los procesos bioquímicos que ocurren antes y después del parto, así como la fisiología y bioquímica de la lactancia temprana, eventos de vital importancia para la salud, producción y rentabilidad en bovinos lecheros.

Sociedades Rurales, Producción y Medio Ambiente, 2014

Resumen. En este estudio se presentan elementos científicos y técnicos sobre el periodo de transi... more Resumen. En este estudio se presentan elementos científicos y técnicos sobre el periodo de transición de la vaca lechera, en el cual factores como la modificación de las poblaciones microbianas en el rumen, el metabolismo hepático y la recuperación, tanto de las paredes ruminales como de la glándula mamaria, son componentes esenciales en las adaptaciones previas a la lactancia. La revisión hace hincapié en la necesidad de un manejo nutricional especial durante el balance energético negativo (ben) con el fin de alcanzar un adecuado equilibrio entre el consumo de energía, por parte del animal, y la energía requerida para el mantenimiento y la preñez (en la vaca gestante), y el mantenimiento y la lactancia (en la vaca lactante). Por lo tanto, la información revisada permitirá difundir de manera más concisa los conocimientos relacionados con el entendimiento del metabolismo energético. La compilación de estudios publicados también pretende hacer más accesible la comprensión de los eventos bioquímicos y endocrinos que ocurren alrededor del parto, fisiología y bioquímica del periodo seco y el posparto temprano, eventos de vital importancia para la salud, la producción y la rentabilidad de las vacas lecheras.

Actualidad Económica, 2021

This article aims to characterize the Software and Computer Services Sector from the point of vie... more This article aims to characterize the Software and Computer Services Sector from the point of view of the contribution it makes to local development, with special emphasis on the possible consequences for the problem of work rotation in the case of Tandil. For the study, a review of the literature, analysis of national reports, interviews with key actors and compilation of data on companies in the sector were developed. Among the main results it found is a tension between the incorporation of personnel to increase sales to the foreign market and the expansion of exports to favor the incorporation of human resources, without pressure to lower wages.

The role of enhanced cardiac fibroblast glycosylation products on collagen synthesis

The FASEB Journal, 2012

Author(s): Maya-Ramos, Lisandro | Advisor(s): Kornberg, Thomas B | Abstract: Bilaterality, is the... more Author(s): Maya-Ramos, Lisandro | Advisor(s): Kornberg, Thomas B | Abstract: Bilaterality, is the predominant body plan in the animal kingdom. Cells either from the left or right side, rarely cross the body midline plane throughout life, as evidenced by naturally occurring bilateral gynandromorphs. However, it has been a longstanding mystery how this evolutionary conserved ipsilaterality is achieved in bilaterians, including humans. Using the chick embryo as a model, we show that extracellular matrix (ECM) and caspase-3-dependent programmed cell death (PCD) localize to the primitive streak (PS) midline. Both, faithfully direct ipsilateral ingression through the inhibition of contralateral cellular invasion. PS midline PCD is dependent on ECM accumulation. Suppression of these components results in contralateral cellular invasion. Remarkably, induced PCD alone, without ECM, is sufficient to rescue ipsilateral gastrulation. Our findings reveal that PCD actively patterns ipsilaterality...

Programmed cell death along the midline axis patterns ipsilaterality in gastrulation

Science, 2020

Apoptosis prevents left-right crossing Animals generally display a bilateral body plan, with symm... more Apoptosis prevents left-right crossing Animals generally display a bilateral body plan, with symmetry between the left and right sides. Maya-Ramos and Mikawa examined the mechanism that prevents the crossing of cells between sides. Using chick embryos, they show that cellular mixing between sides is prevented by a barrier at the embryonic midline that involves programmed cell death and the extracellular matrix. This work demonstrates the dependence of normal development on programmed cell death during the gastrulation stage. Science , this issue p. 197

Revista de Ciências Agrárias, 2018

Na busca de alternativas para o controle de fitonematoides, vem sendo estudado o efeito nematicid... more Na busca de alternativas para o controle de fitonematoides, vem sendo estudado o efeito nematicida de metabolitos secundários ou resíduos vegetais. Dessa forma, a manipueira, resíduo líquido da industrialização da mandioca (Manihot esculenta), tem como composição glicosídeos cianogênicos com propriedades antimicrobianas. Objetivou-se avaliar o potencial da manipueira aplicada no solo, visando o controle de Meloidogyne javanica na cultura da soja. A manipueira foi aplicada nas concentrações de 0, 10, 20, 30, 40, 50, 60, 70, 80, 90 e 100%. O delineamento experimental foi inteiramente casualizado, em arranjo fatorial 11 × 2 (concentrações de manipueira × formas de aplicação-única e parcelada), com cinco repetições. As plantas de soja foram inoculadas com 3000 ovos e J2 de M. javanica por vaso. Sessenta dias após a primeira aplicação da manipueira, foram avaliadas características agronômicas e de parasitismo. A aplicação única da manipueira promoveu maior crescimento e desenvolvimento radicular, bem como redução do número de ovos e J2 na raiz e do fator de reprodução de M. javanica, para todas as concentrações. A aplicação parcelada teve maior efeito na redução do número de galhas e massas de ovos. As concentrações letais de manipueira para 50% da população de nematoides no solo e na raiz foram de 37,90% e 29,67%, respetivamente.

Pesquisa Agropecuária Tropical, 2016

Manipueira, a liquid residue obtained from the cassava industrialization, shows high toxicity to ... more Manipueira, a liquid residue obtained from the cassava industrialization, shows high toxicity to the microbial diversity. This study aimed at evaluating the potential of manipueira applied to the soil to control Meloidogyne incognita in soybean. A completely randomized design, in a 2 x 11 factorial scheme, was used, consisting of two application forms of manipueira (single and two applications), in eleven concentrations (0 %, 10 %, 20 %, 30 %, 40 %, 50 %, 60 %, 70 %, 80 %, 90 % and 100 %), with five replications per treatment. Some agronomic traits and parasitism characteristics were also evaluated. The plants that received a single application of manipueira showed a gain of 100.41 % in root length, while the volume and fresh root mass showed gains of 81.52 % and 28.11 %, respectively, with the two applications. Regarding parasitism, the single application was more effective in reducing the number of juveniles in the soil and roots, where the concentrations of manipueira to kill 50 ...

Comunicata Scientiae, 2017

To obtain high seed quality, good fertilization practices are essential due to its influence not ... more To obtain high seed quality, good fertilization practices are essential due to its influence not only on seed yield and weight, but also controlling the development of seedlings anomalies. Therefore, the aim of this study was to evaluate the effects of different forms of fertilization on yield and physiological quality of upland rice seeds. It was used nitrogen fertilization in coverage as urea and foliar fertilization with macro and micronutrients. The treatments consist of various sources and forms of fertilization, in a randomized block design, as follows: covering at tillering with N at 34 kg ha-1; covering at floral primordium with N at 34 kg ha-1; foliar fertilization at tillering; foliar fertilization in floral primordium; covering with N at 34 kg ha-1 in tillering and foliar fertilization in floral primordium; only basic fertilization and treatment without fertilization. The results showed that the application of nitrogen fertilizer with urea, at tillering and floral primord...

Childhood Trauma in U.S.-Mexico Border Area Mental Health and Primary Care Clinics

PsycEXTRA Dataset

Journal of Developmental Biology, 2013

The proepicardium is a transient extracardiac embryonic tissue that gives rise to the epicardium ... more The proepicardium is a transient extracardiac embryonic tissue that gives rise to the epicardium and a number of coronary vascular cell lineages. This important extracardiac tissue develops through multiple steps of inductive events, from specification of multiple cell lineages to morphogenesis. This article will review our current understanding of inductive events involved in patterning of the proepicardium precursor field, specification of cell types within the proepicardium and their extension and attachment to the heart.

American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, 2012

We examined the role that enzymatic protein O-GlcNAcylation plays in the development of diabetic ... more We examined the role that enzymatic protein O-GlcNAcylation plays in the development of diabetic cardiomyopathy in a mouse model of Type 2 diabetes mellitus (DM2). Mice injected with low-dose streptozotocin and fed a high-fat diet developed mild hyperglycemia and obesity consistent with DM2. Studies were performed from 1 to 6 mo after initiating the DM2 protocol. After 1 mo, DM2 mice showed increased body weight, impaired fasting blood glucose, and hyperinsulinemia. Echocardiographic evaluation revealed left ventricular diastolic dysfunction by 2 mo and O-GlcNAcylation of several cardiac proteins and of nuclear transcription factor Sp1. By 4 mo, systolic dysfunction was observed and sarcoplasmic reticulum Ca2+ ATPase expression decreased by 50%. Fibrosis was not observed at any timepoint in DM2 mice. Levels of the rate-limiting enzyme of the hexosamine biosynthetic pathway, glutamine:fructose-6-phosphate amidotransferase (GFAT) were increased as early as 2 mo. Fatty acids, which are...

American Journal of Physiology-Cell Physiology, 2014

Excess enzyme-mediated protein O-GlcNAcylation is known to occur with diabetes mellitus. A charac... more Excess enzyme-mediated protein O-GlcNAcylation is known to occur with diabetes mellitus. A characteristic of diabetic cardiomyopathy is the development of myocardial fibrosis. The role that enhanced protein O-GlcNAcylation plays in modulating the phenotype of cardiac fibroblasts (CF) is unknown. To address this issue, rat CF were cultured in normal glucose (NG; 5 mM glucose) or high-glucose (HG; 25 mM) media for 48 h. Results demonstrate that CF cultured in HG have higher levels (∼50%) of overall protein O-GlcNAcylation vs. NG cells. Key regulators of collagen synthesis such as transforming-growth factor-β1 (TGF-β1), SMADs 2/3, and SMAD 7 protein levels, including those of arginase I and II, were altered, leading to increases in collagen levels. The nuclear transcription factor Sp1 and arginase II evidence excess O-GlcNAcylation in HG cells. Expression in CF of an adenovirus coding for the enzyme N-acetylglucosaminidase, which removes O-GlcNAc moieties from proteins, decreased Sp1 a...

Implementação de um sistema FDMA. Análise de desempenho na presença de ruído e não-linearidade

The work reported in this paper deals with the impact of a nonlinear channel with noise in a FDMA... more The work reported in this paper deals with the impact of a nonlinear channel with noise in a FDMA system. The system is simulated using a time domain simulator, based on simulink. Five GSM channels are combined and then traverse a nonlinear noisy channel. Finally some results are discussed..