Thesis (Ph. D.)--University of Chicago, 1917. / Distributed by the university of Chicago Libraries, Chicago, Illinois. Reprinted from the Botanical gazette, Vol. LXVII, No. 2, February 1919. Includes bibliographical references (p. 144-146).

Thesis (Ph. D.)--University of Chicago, 1917. / Distributed by the university of Chicago Libraries, Chicago, Illinois. Reprinted from the Botanical gazette, Vol. LXVII, No. 2, February 1919. Bibliography: p. 144-146.

Thesis (Ph. D.)--University of Chicago, 1917. / Distributed by the university of Chicago Libraries, Chicago, Illinois. Reprinted from the Botanical gazette, Vol. LXVII, No. 2, February 1919. Bibliography: p. 144-146.

Químico Ambiental / La minería del cobre es una actividad económica muy importante para el país, sin embargo, presenta diversos riesgos ambientales, principalmente asociados a la disposición de relaves mineros. Uno de los métodos utilizados en la remediación de estos relaves es la fitoestabilización, que se enfoca en generar una cobertura vegetal que permita la estabilización y contención del relave. El presente trabajo tiene por objetivo evaluar la capacidad de Atriplex nummularia, en conjunto con las enmiendas orgánicas Perl Humus y compost, para la fitoestabilización de un relave minero de Chile (Tranque de Relaves Ovejería), con respecto a Cu, Mo y S. Para esto se implementó un ensayo en invernadero con macetas con tres sustratos: T1 (relave), T2 (Relave + Perl Humus) y T3 (Relave + compost). La proporción de la enmienda orgánica fue de 5% m/m. El sustrato fue caracterizado para: CE, pH, N, P, K, entre otros. La determinación de biomasa seca de tejido vegetal (aéreo y radicular) y de las concentraciones de Cu, Mo y S, tanto en sustrato como en tejido vegetal, se realizó a los 60 y 120 días. Con estos resultados, se determinó el índice de translocación (Ti) y el factor de bioconcentración (FBC). Al final del ensayo, se encontró que la biomasa aérea y radicular fue mayor en los tratamientos con enmiendas orgánicas, siendo el tratamiento con Perl Humus (T2) en el que se generó la mayor biomasa de tejido aéreo. Las concentraciones de Cu (7,3–10,2 mg kg-1) y Mo (1,0–3,0 mg kg-1) en tejido aéreo de A. nummularia no presentaron niveles tóxicos (Cu>20 mg kg-1; Mo>1 mg kg-1), excepto en el tratamiento con compost (T3), en que los niveles de Mo fueron 10,2 mg kg.1. En cada tratamiento, las concentraciones de S en tejido aéreo (7319–24452 mg kg-1) superan los valores encontrados en suelos agrícolas. En relación con el índice de translocación (Ti), Cu (0,026–0,19), Mo (0,27–1,11) y S (0,25–0,93) mostraron valores menores a 1 en todos los tratamientos, excepto para Mo en relave (T1). Los valores más bajos de Ti fueron para el tratamiento con Perl Humus. Esto indicaría que en este tratamiento A. nummularia presenta una mayor acumulación de Cu, Mo y S en raíz que en los otros tratamientos, propiedad que favorece la fitoestabilización del relave. Respecto al factor de bioconcentración (FBC), en todos los tratamientos y tanto x para tejido aéreo como para raíz, los valores para Cu (0,0059-0,22) y Mo (0,03-0,36) fueron menores a 1 y los valores para S fueron mayores a 1 (9-57,5). Los resultados del factor de bioconcentración indican que el elemento que más se absorbe por el tejido vegetal es S, siendo el tratamiento con Perl Humus en el que se observa la mayor absorción. Mediante el análisis de los resultados, es posible establecer que la adición de enmiendas orgánicas al relave minero aumenta el potencial de fitoestabilización de A. nummularia, respecto a Cu, Mo y S. La enmienda Perl Humus presentó ventajas sobre el compost, principalmente para la acumulación en raíz de Cu y S. Por esto, se podría recomendar el uso de esta especie vegetal ayudada por la enmienda orgánica Perl Humus para la estabilización química de relaves con alto contenido de Cu y S. / Copper mining is a very important economic activity for the country, however, it presents several environmental risks, mainly associated with the disposal of mine tailings. One of the methods used in the remediation of these tailings is the phytostabilization, which focuses on generating a vegetative cap that allows the stabilization and containment of the tailings. The present work aims to evaluate the capacity of Atriplex nummularia, in conjunction with the organic amendments Perl Humus and compost, to achieve the phytostabilization of a Chilean mine tailings (Tranque de Relaves Ovejería), regarding Cu, Mo and S. For this, a greenhouse experiment was implemented with three substrata: T1 (Tailings), T2 (Tailings + Perl Humus) and T3 (Tailings + compost). The proportion of the amendments was 5% w/w. The substrata was characterized for: EC, pH, N, P, K, among others. The determination of dry biomass of vegetal tissue (aerial and root) and the concentration of Cu, Mo and S, both in substrate and in plant tissue, was carried out at 60 and 120 days. With these results, the translocation index (Ti) and the bioconcentration factor (FBC) were determined. At the end of the experiment, it was found that the aerial and root biomass was higher in the treatments with organic amendments, being the treatment with Perl Humus (T2) in which the highest biomass of aerial tissue was generated. The concentration of Cu (7,3–10,2 mg kg-1) and Mo (1,0–3,0 mg kg-1) in aerial tissue of A. nummularia did not present toxic levels (Cu>20 mg kg-1; Mo>1 mg kg-1), except for the treatment with compost (T3), in which the levels of Mo were 10,2 mg kg.1. In each treatment, the concentrations of S in aerial tissue (7319–24452 mg kg-1) excedes the values found in agricultural soils. Regarding the translocation index (Ti), Cu (0,026–0,19), Mo (0,27–1,11) and S (0,25–0,93) showed values lower than 1 in all treatments, except for Mo in tailings (T1). The lowest Ti values were for the Perl Humus treatment. This would indicate that in this treatment A. nummularia presents a higher acumulation of Cu, Mo and S in root than in the other treatments, property that favors the phytostabilization of the tailings. Concerning the bioconcentration factor (FBC), in all the treatments and for both aerial and xii root tissue, the values for Cu (0,0059-0,22) and Mo (0,03-0,36) were less than 1 and the values for S were greater than 1 (9-57,5). The results of the bioconcentration factor indicate that the element that is more absorbed by the plant tissue is S, being the treatment with Perl Humus in which the greater absorption is observed. By analyzing the results it is possible to establish that the adition of organic amendments to the mine tailings increases the phytostabilization potential of A. nummularia, regarding Cu, Mo and S. The amendment Perl Humus showed advantages over compost, mainly for the acumulation of Cu and S in roots. For this reason, the use of this species, aided by the organic amendment Perl Humus, could be recommended for the chemical stabilization of mine tailings with high content of Cu and S.

OMSB het gunstig op bemesting in die saailingfase, waar die groeimedium ‘n swak voedingstatus gehad het gereageer. ‘n Swak reaksie op bemesting na verplanting is verkry, waarskynlik omdat die voedingstatus van die grand waarin plante gevestig is, gunstig was. Die invloed van suurheidsgraad op OMSB, veral op saailinge, word moontlik oorskat. Aangesien die reaksie van OMSB op kaliumlnatriumsout-bemesting beperk was, is dit moontlik dat die gewas soute in plantweefsel stoor, en dus ‘n luukse voeder van elemente soos kalium en natrium is. Terrasorb verbeter die waterhouvermoë van gronde beduidend. Op swaar grande kan hierdie verhoging in waterhouvermoë egter ‘n negatiewe invloed op die groeikragtigheid van plante hê. Die effektiwiteit van Terrasorb hang grootliks van die voghuishouding af. Indien vog beperkend is, kan Terrasorb die groei van OMSB in beide ligte en swaarder gronde bevorder, terwyl dit die groei van OMSB in kleigrond kan inhibeer indien vog vrylik beskikbaar is. Gedurende die tydperk Oktober 1990 tot Februarie 1991, het OMSB plante in Pretoria gemiddeld 20g nat materiaal/dag en 6.8g droë materiaal (DM) per dag geproduseer. Dit is ongeveer nege ton nat materiaal/ha en drie ton DM/ha, oor ‘n periode van 150 dae. Die produksiepotensiaal en groeitempo van OMSB vergelyk besonder gunstig met die van ander weidingsgewasse. Die graad van terugsnoei voor verplanting, het binne redelike perke, nie ‘n beduidende negatiewe effek op saailingontwikkeling gehad nie. Vog was egter vrylik beskikbaar en onder meer stremmende toestande kan groei waarskynlik gestrem word. Die graad van ontblaring na verplanting het 'n beduidende invloed op die herstelvermoë van OMSB gehad. Verskille in groeitempo is tussen plante wat tot op verskillende hoogtes gesnoei is, gemeet. Die gemiddelde groeitempo van plante onderworpe aan die somer snoeibehandeling, was effens laer as dié van plante onderworpe aan 'n lente behandeling. Hierdie plante het egter 'n korter aktiewe groeiperiode as plante wat in die lente gesnoei is, gehad. 121 GVE (Grootvee eenheid) weidae/ha en 253 GVE weidae/ha is met onderskeidelik die matige en swaar benuttings verkry, wat aandui dat 'n relatief hoë weidingskapasiteit dus met OMSB verkry kan word. Die herstelvermoë van OMSB, soos gemeet in terme van DM opbrengs en met behulp van oppervlakte projeksies, was selfs na 'n totale benutting, relatief goed. Plante wat totaal benut was, was egter tot 'n baie groter mate aan afsterwing onderworpe. Hierdie tendense is met die herfs-, winter- en lente benutting gevind. OMSB is waarskynlik beter aangepas by matige benutting. Plante wat straf ontblaar word, is waarskynlik meer gevoelig vir stremming. OMSB kan meer as een maal per jaar effektief benut word, mits ontblaring nie oormatig is nie. Die weidingskapasiteit van die gewas kan moontlik met effektiewe bestuur aansienlik verhoog word. Diereprestasie mag ook, wanneer 'n matige weidruk toegepas word, as gevolg van die seleksie van 'n hoër kwaliteit dieet toeneem. ENGLISH: The aim of this study was to determine the value of Oldman Saltbush (OMS) as an alternative fodder in areas with a relatively high rainfall. Aspects that were studied were establishment. reaction to fertilization. production and reaction to utilization. OMS reacted positively to fertiliser in the seedling phase. where the growing medium had a poor nutrient status. a Poor reaction to fertilisation was obtained after transplanting. probably because of the favourable nutrient status of the particular soil. The influence of soil acidity. on OMS. particularly on seedlings. is probably overrated. As OMS showed a limited reaction to sodium/potassium fertilisation. it is argued that OMS stores salts in plant tissue and probably is a luxury feeder of elements such as potassium and sodium. Terrasorb improves the water holding capacity of soil significantly. On heavier soil this increase in water holding capacity could have a negative effect. The effectivity of Terrasorb depends greatly on the current moisture situation. Terrasorb could enhance growth in both light and heavy soil if moisture is a limiting factor. Where moisture is not limiting. growth in heavy soil could be inhibited. During the period October 1990 until February 1991. OMS plants in Pretoria produced 20g wet material and 6.8g dry material (OM) per day on average. This amounts to approximately nine tons of wet material/ha and three tons of DM/ha. in 150 days. The production of OMS compares favourably with that of other fodder crops. The degree of defoliation before transplanting did not. within limits. had a significant negative influence on seedling development. Moisture. however. was not a limiting factor and growth probably could be inhibited under stress. The degree of defoliation after transplanting, had a significant effect on the recovery of OMS. Differences in growth rate were found between plants defoliated to different heights. The mean growth rate of plants defoliated during summer, was somewhat lower as the growth rate found for plants defoliated during spring, probably because the recovery period was shorter. A total of 121 Large stock unit (LSU) grazing days/ha and 253 LSU grazing days/ha were obtained with the moderate and severe utilizations respectively, which shows that a relatively high grazing capacity can be obtained with OMS. The recovery potential of OMS as measured in terms of DM yield and with area projections was, even after severe utilization, relatively good. The survival rate of OMS was, however, significantly higher when plants were moderately utilized. This was found with autumn-, winter- and spring utilization. OMS is probably better adapted to moderate utilization. Plants that are severely utilized, are probably more susceptible to stress. OMS can be utilized effectively more than once a year, if defoliation is moderate. The grazing capacity of this crop could possibly be increased with effective management, while animal production might increase with the selection of a higher quality diet, when moderate grazing pressures are applied. / Dissertation (MSc(Agric))--University of Pretoria, 2010. / Plant Production and Soil Science / unrestricted

Made available in DSpace on 2014-12-17T15:41:48Z (GMT). No. of bitstreams: 1 ElianeGA_DISSERT.pdf: 4101780 bytes, checksum: 9b7501315a910595077f44b678b21c52 (MD5) Previous issue date: 2009-08-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This study aimed to analyze the effect of a saline solution on growth and chemical composition of Atriplex nummularia, shrubby plant, absorbing salts used in the diet of animals and the management of water and saline soils. These plant seedlings were planted and grown in a reserved area at the Federal University of Rio Grande do Norte. The plantation was divided into two blocks, in which one of them was irrigated with saline solution with a concentration of 2840 mgL-1 of NaCl and the second group was irrigated with drinking water. After six months, the plants were collected, harvested and divided into three parts: leaf, thin and thick stem. Monthly, dimension measurements were carried out for cataloging the growth of Atriplex. Ion Chromatography (IC) and Optical Emission Spectroscopy Inductively Coupled Plasma (ICP-OES) were used to analyze the chemical composition of the partition plant parts. The results of these analyses revealed that an absorption process of anions and cations by Atriplex nummularia plant during its growth was achieved, in particular by a higher concentration of sodium and chloride ions. Scanning electron microscopy images showed and confirmed the presence of small crystals on the leaf surface. Electrical conductivity and pH measurements of the aerial parts of the plant were carried out and these results showed that the leaf is the plant part where there is a largest concentration of ions. In addition, measurements of specific surface were obtained from irrigated plants with saline solution, achieving higher surface area, in all cases. Plant dimensions obtained monthly showed that the plants irrigated with water grew 5% more than those plants irrigated with saline solution. Based on results obtained, Atriplex plant showed a higher potential to survive and adapt to environments (aquatic or geological) with high levels of salinity and this property can be used as a tool for removing salts/metals from industrial contaminated soils and effluents. / O presente estudo teve como objetivo analisar o efeito da aplica??o de uma solu??o salina no crescimento e na composi??o qu?mica da Atriplex nummularia, planta arbustiva, absorvedora de sais utilizada na dieta de animais e no manejo de ?guas e solos salinos. Mudas desta erva foram plantadas e cultivadas no Horto da Universidade Federal do Rio Grande do Norte. A planta??o foi dividida em dois blocos, no qual um deles foi irrigado com solu??o salina com concentra??o de 2840 mgL-1 de cloreto e o outro irrigado com ?gua pot?vel. Ap?s seis meses do plantio as plantas foram colhidas e dividas em tr?s partes: folha, caule fino e caule grosso. O crescimento da Atriplex foi avaliado atrav?s de medidas mensais. Para a caracteriza??o qu?mica fez-se necess?rio o uso de t?cnicas anal?ticas como: Cromatografia de ?ons (IC) e Espectroscopia de Emiss?o ?ptica por Plasma Indutivamente Acoplado (ICP-OES). Os resultados dessas an?lises destacaram a diversidade de ?nions e c?tions absorvidos pela planta durante seu processo evolutivo, apresentando em especial uma maior concentra??o dos ?ons s?dio e cloreto. A Microscopia Eletr?nica de Varredura identificou a presen?a de pequenos cristais na superf?cie da folha. An?lises de condutividade el?trica das partes a?reas da planta foram realizadas juntamente com medidas do potencial hidrogeni?nico e essas mostraram que na folha encontram-se as maiores concentra??o de ?ons. Medidas da ?rea superficial espec?fica das plantas irrigadas com solu??o salina apresentaram maior ?rea superficial. As medidas mensais realizadas durante todo o cultivo mostraram que as plantas irrigadas com ?gua pot?vel se desenvolveram 5% a mais do que as plantas cultivadas com solu??o salina. Com base em todos os resultados obtidos durante o estudo foi conclu?do que a Atriplex ? uma planta que apresenta potencialidade em sobreviver e adaptar-se a ambientes salinos, podendo ser utilizada como uma fonte absorvedora de sais dos solos contaminados por efluentes resultantes de processos industriais nos quais tem a ?gua salina como produto final de seus processos.

Rangelands in Jordan are deteriorated due to a combination of harsh environmental conditions and human misuse. Jordan is importing increasingly large quantities of meat and animal products to meet the demand from its growing population. Sheep are supplementaQ ly fed during the dry season and large quantities of grain supplements are imported every year. Significant success has been attained in the establishment of Atriplex nummularia lindl. (ATNU) in Jordan. There is, however, a general lack of adequate research to determine if ATNU is effectively utilized by local sheep, to what extent it is utilized and to what extent it tolerates grazing. The objectives of this research were to determine the effects of grazing ATNU at two intensities (moderate and heavy) on subsequent production of ATNU browse, and on sheep live weight. Results of this research showed that HNU shrubs are grazing tolerant, they are stimulated by grazing to produce more forage than the non-grazed shrubs. When heavily grazed in the fall, they showed greater compensatory growth than moderately grazed shrubs, but the moderately grazed shrubs gave sustained production better than those heavily grazed in both good and bad years. Sheep grazing ATNU shrubs with native forage (grasses and forbs) in the fall gained more weight at the moderately grazed treatments. The amount of sheep-live-weight gain was positively affected by the amount of food intake per sheep metabolic body weight and inversely affected by the percentage of ATNU browse in the diet. ATNU although less preferred by sheep than grasses and forbs, could probably be used up to 40% of the diet and still maintain sheep live weight. ATNU is a good source of forage especially during the dry season, it provides (with native grasses and forbs) a high-quality forage and may considerably reduce the amount of costly supplements imported to Jordan.

Memoria para optar al Título Profesional de Ingeniero Forestal / Las Comunidades Agrícolas, corresponden a un particular tipo de tenencia de la tierra, donde convive una propiedad común con una individual. Como una alternativa para aumentar la productividad de las praderas, se planteó, en la década de 1970 , la posibilidad de forestar los terrenos degradados por el uso excesivo y destinados al pastoreo del ganado, con especies forrajeras de alto valor nutritivo y palatabilidad para el ganado, aprovechando los beneficios que otorgaba el D.L. 701 de 1974. Así, a partir de 1975 se desarrolló un proceso de forestación en el secano de la IV Región que ha permitido establecer cerca de 60.000 ha de arbustos forrajeros, estableciéndose más de 10.000 ha en terrenos pertenecientes a las denominadas Comunidades Agrícolas.

Memoria para optar al Título Profesional de Ingeniera Agrónoma / El presente estudio busca evaluar los eventuales cambios en las propiedades químicas de un suelo en condición de ladera con severos signos de degradación, sometido a un sistema de cosecha de agua de lluvia (líneas de piedra). Durante el año 2011, se construyeron 3 líneas de piedra junto con el establecimiento de Atriplex nummularia Lindl. y aplicación de estiércol de caprino (4 Mg ha-1). Para dos temporadas, 2014 y 2015, se evaluaron pH, conductividad eléctrica (CE), materia orgánica (MO) y macronutrientes totales (NPK); además se determinó el crecimiento (altura y masa seca total) y NPK tanto en hoja como en tallo de las plantas. El estiércol en general mostró un aumento significativo pero temporal en el pH, el contenido de MO y NPK evaluados en los suelos. Además, se observaron incrementos de CE en la superficie del suelo, siendo asociados a la caída de las hojas de la planta. Se aprecia un menor crecimiento de A. nummularia bajo la línea de piedra y, aunque sin diferencias significativas, el crecimiento fue levemente mayor en el tratamiento con estiércol animal, al igual que para los NPK medidos en la planta. El mayor crecimiento vegetal sobre la línea de piedra, contribuye directamente a la protección del suelo contra los procesos de erosión dominantes. Además, la incorporación del estiércol de caprino generó un mejoramiento en las propiedades químicas de suelo evaluadas, pero su efecto al ser temporal determina que es necesario considerar un plan de aplicaciones periódicas para obtener un efecto prolongado en el tiempo.

BRILHANTE, J. C. A. Contribuição de solutos orgânicos e inorgânicos no potencial osmótico de folhas de atriplex nummularia submetidas ao NaCl, SECA E PEG. 2006. 195 f. Dissertação (Mestrado em Agronomia/Fitotecnia) - Centro de Ciências Agrárias, Universidade Federal do Ceará, Fortaleza, 2006. / Submitted by Francisco Lacerda (lacerda@ufc.br) on 2014-07-15T19:39:06Z No. of bitstreams: 1 2006_dis_jcabrilhante.pdf: 1463347 bytes, checksum: 7f27bb350d9b7a07d32ec4ecef65c90f (MD5) / Approved for entry into archive by José Jairo Viana de Sousa(jairo@ufc.br) on 2014-07-16T20:06:44Z (GMT) No. of bitstreams: 1 2006_dis_jcabrilhante.pdf: 1463347 bytes, checksum: 7f27bb350d9b7a07d32ec4ecef65c90f (MD5) / Made available in DSpace on 2014-07-16T20:06:44Z (GMT). No. of bitstreams: 1 2006_dis_jcabrilhante.pdf: 1463347 bytes, checksum: 7f27bb350d9b7a07d32ec4ecef65c90f (MD5) Previous issue date: 2006 / Uma das características fisiológicas mais importantes das halófitas pertencentes ao gênero Atriplex é a enorme habilidade de acumular solutos orgânicos e inorgânicos com o intuito de se ajustar osmoticamente em condições de elevada salinidade e deficiência hídrica. Contudo estudos compreensivos sobre a contribuição relativa desses solutos inorgânicos e orgânicos no ajustamento osmótico de folhas dessas halófitas ainda são poucos explorados na literatura. Esse trabalho pretende pela primeira vez na literatura fazer um estudo detalhado, da participação e da contribuição relativa da maioria dos solutos orgânicos e inorgânicos no potencial osmótico de folhas de Atriplex nummularia, submetidas a concentrações crescentes de NaCl, ciclos sucessivos de seca e ao polietileno glicol (PEG). Para responder as questões acima mencionadas foram conduzidos três grandes experimentos seqüenciais. No primeiro experimento, mudas de Atriplex nummularia com quatro meses de idade, foram cultivadas em vasos de argila contendo como substrato areia, sendo irrigadas a cada dois dias com solução contendo concentrações crescentes de NaCl (0, 100, 200, 300 e 400 mmol L-1) durante 120 dias. O experimento foi realizado em condições de casa de vegetação. No segundo experimento, mudas de A. nummularia, com idade de 18 meses foram transplantadas para recipientes de polietileno contendo 5.0 kg de vermiculita, em condições de casa de vegetação, onde foram submetidas aos seguintes tratamentos (Controle; seca; NaCl + seca; NaCl) por três ciclos sucessivos de seca-reidratação (3 semanas) seguido de uma recuperação no final do último ciclo (após 48 h). No terceiro experimento, plântulas de A.nummularia, com idade de dois meses foram transplantadas para cultivo hidropônico em vasos plásticos com capacidade para 0,8 em sala de crescimento sob condições controladas onde sofrerão um pré-condicionamento com ou sem NaCl por duas semanas. Após foram submetidas aos seguintes tratamentos (controle; PEG; NaCl; NaCl + PEG). Em conclusão, os resultados da presente investigação demonstram que as plantas de Atriplex nummularia foram capazes de manter o seu crescimento mesmo em condições de alta salinidade, principalmente pela capacidade de manutenção de seu status hídrico. Os resultados também sugerem que a GB é o maior soluto orgânico envolvido com o ajustamento osmótico (AO) do citoplasma e que sua acumulação parece ser uma resposta adaptativa ao estresse provocado pelo NaCl. Em adição, o íons salinos Na+ e Cl- contribuíram para a maioria do AO das folhas submetidas ao NaCl. O impacto relativo do K+ sobre o AO das folhas foi reduzido consideravelmente com o aumento da dose externa de NaCl. Os resultados evidenciam também que o pré-condicionamento com NaCl influenciou positivamente no crescimento de Atriplex nummularia, em condições de seca, evidenciado pelo maior acúmulo de massa seca e melhor status hídrico das folhas. Dentre os solutos inorgânicos analisados, o Na+ e o Cl- foram os que mais contribuíram para a osmorregulação das folhas em condições de deficiência hídrica. Enquanto, GB foi o soluto orgânico mostrou o maior percentual de contribuição para o potencial osmótico. Entretanto os resultados mostraram que o pré-condicionamento das plântulas de Atriplex nummularia com NaCl não foram capazes de atenuar os efeitos induzidos pelo PEG.