Statistical modeling for analyzing grain yield of durum wheat under rainfed conditions in Azad Jammu Kashmir, Pakistan / Modelagem estatística para analisar o rendimento de grãos de trigo durum sob condições de chuva em Azad Jammu Kashmir, Paquistão

One of the most important traits that plant breeders aim to improve is grain yield which is a highly quantitative trait controlled by various agro-morphological traits. Twelve morphological traits such as Germination Percentage, Days to Spike Emergence, Plant Height, Spike Length, Awn Length, Tillers/Plant, Leaf Angle, Seeds/Spike, Plant Thickness, 1000-Grain Weight, Harvest Index and Days to Maturity have been considered as independent factors. Correlation ,regression, and principal component analysis (PCA) are used to identify the different durum wheat traits, which significantly contribute to the yield. The necessary assumptions required for applying regression modeling have been tested and all the assumptions are satisfied by the observed data. The outliers are detected in the observations of fixed traits and Grain Yield. Some observations are detected as outliers but the outlying observations did not show any influence on the regression fit. For selecting a parsimonious regression model for durum wheat, best subset regression, and stepwise regression techniques have been applied. The best subset regression analysis revealed that Germination Percentage, Tillers/Plant, and Seeds/Spike have a marked increasing effect whereas Plant thickness has a negative effect on durum wheat yield. While stepwise regression analysis identified that the traits, Germination Percentage, Tillers/Plant, and Seeds/Spike significantly contribute to increasing the durum wheat yield. The simple correlation coefficient specified the significant positive correlation of Grain Yield with Germination Percentage, Number of Tillers/Plant, Seeds/Spike, and Harvest Index. These results of correlation analysis directed the importance of morphological characters and their significant positive impact on Grain Yield. [...].

Uma das características mais importantes que os produtores de plantas visam melhorar é o rendimento de grãos, que é uma particularidade altamente quantitativa e controlada por várias características agromorfológicas. Foram considerados 12 traços morfológicos como fatores independentes, como Porcentagem de Germinação, Dias para Emergência da Espiga, Altura da Planta, Comprimento da Espiga, Comprimento da Aresta, Perfilhos /Planta, Ângulo da Folha, Sementes /Espiga, Espessura da Planta, Peso de 1000 Grãos, Índice de Colheita e Dias até a Maturidade. A correlação, regressão e análise de componentes principais (em inglês Principal Component Analysis (PCA)) são usadas para identificar as diferentes características do trigo duro, que contribuem significativamente para o rendimento. As suposições necessárias exigidas para a aplicação da modelagem de regressão foram testadas e todas as suposições são adequadas de acordo com os dados observados. Os outliers são detectados nas observações de características fixas e rendimento de grãos. Algumas observações são detectadas como outliers, mas as observações outliers não mostraram qualquer influência no ajuste da regressão. Para selecionar um modelo de regressão parcimonioso para o trigo duro, foram aplicadas tanto a melhor regressão de subconjunto quanto as técnicas de regressão stepwise. A melhor análise de regressão de subconjunto revelou que a porcentagem de germinação, perfilhos /planta e sementes /espiga tem um efeito de aumento acentuado, enquanto a espessura da planta tem um efeito negativo sobre o rendimento do trigo duro. Enquanto a análise de regressão passo a passo identificou que as características, porcentagem de germinação, perfilhos/planta e sementes /espiga contribuem significativamente para aumentar a produtividade do trigo duro. O coeficiente de correlação simples especificou a correlação positiva significativa do [...].

Statistical modeling for analyzing grain yield of durum wheat under rainfed conditions in Azad Jammu Kashmir, Pakistan

Abstract One of the most important traits that plant breeders aim to improve is grain yield which is a highly quantitative trait controlled by various agro-morphological traits. Twelve morphological traits such as Germination Percentage, Days to Spike Emergence, Plant Height, Spike Length, Awn Length, Tillers/Plant, Leaf Angle, Seeds/Spike, Plant Thickness, 1000-Grain Weight, Harvest Index and Days to Maturity have been considered as independent factors. Correlation, regression, and principal component analysis (PCA) are used to identify the different durum wheat traits, which significantly contribute to the yield. The necessary assumptions required for applying regression modeling have been tested and all the assumptions are satisfied by the observed data. The outliers are detected in the observations of fixed traits and Grain Yield. Some observations are detected as outliers but the outlying observations did not show any influence on the regression fit. For selecting a parsimonious regression model for durum wheat, best subset regression, and stepwise regression techniques have been applied. The best subset regression analysis revealed that Germination Percentage, Tillers/Plant, and Seeds/Spike have a marked increasing effect whereas Plant thickness has a negative effect on durum wheat yield. While stepwise regression analysis identified that the traits, Germination Percentage, Tillers/Plant, and Seeds/Spike significantly contribute to increasing the durum wheat yield. The simple correlation coefficient specified the significant positive correlation of Grain Yield with Germination Percentage, Number of Tillers/Plant, Seeds/Spike, and Harvest Index. These results of correlation analysis directed the importance of morphological characters and their significant positive impact on Grain Yield. The results of PCA showed that most variation (70%) among data set can be explained by the first five components. It also identified that Seeds/Spike; 1000-Grain Weight and Harvest Index have a higher influence in contributing to the durum wheat yield. Based on the results it is recommended that these important parameters might be considered and focused in future durum wheat breeding programs to develop high yield varieties.

Resumo Uma das características mais importantes que os produtores de plantas visam melhorar é o rendimento de grãos, que é uma particularidade altamente quantitativa e controlada por várias características agromorfológicas. Foram considerados 12 traços morfológicos como fatores independentes, como Porcentagem de Germinação, Dias para Emergência da Espiga, Altura da Planta, Comprimento da Espiga, Comprimento da Aresta, Perfilhos /Planta, Ângulo da Folha, Sementes /Espiga, Espessura da Planta, Peso de 1000 Grãos, Índice de Colheita e Dias até a Maturidade,. A correlação, regressão e análise de componentes principais (em inglês Principal Component Analysis (PCA)) são usadas para identificar as diferentes características do trigo duro, que contribuem significativamente para o rendimento. As suposições necessárias exigidas para a aplicação da modelagem de regressão foram testadas e todas as suposições são adequadas de acordo com os dados observados. Os outliers são detectados nas observações de características fixas e rendimento de grãos. Algumas observações são detectadas como outliers, mas as observações outliers não mostraram qualquer influência no ajuste da regressão. Para selecionar um modelo de regressão parcimonioso para o trigo duro, foram aplicadas tanto a melhor regressão de subconjunto quanto as técnicas de regressão stepwise. A melhor análise de regressão de subconjunto revelou que a porcentagem de germinação, perfilhos /planta e sementes /espiga tem um efeito de aumento acentuado, enquanto a espessura da planta tem um efeito negativo sobre o rendimento do trigo duro. Enquanto a análise de regressão passo a passo identificou que as características, porcentagem de germinação, perfilhos/planta e sementes /espiga contribuem significativamente para aumentar a produtividade do trigo duro. O coeficiente de correlação simples especificou a correlação positiva significativa do rendimento de grãos com a porcentagem de germinação, número de perfilhos/planta, sementes / espiga e índice de colheita. Esses resultados da análise de correlação direcionaram a importância dos caracteres morfológicos e seu impacto positivo e significativo no rendimento de grãos. Os resultados da PCA mostraram que a maior parte da variação (70%) entre o conjunto de dados pôde ser explicada pelos cinco primeiros componentes. Também identificou que Sementes / Espiga, Peso de 1000 Grãos e Índice de Colheita têm uma maior influência na contribuição para o rendimento do trigo duro. Com base nos resultados, recomenda-se que esses importantes parâmetros possam ser considerados e focados em futuros programas de melhoramento de trigo duro para desenvolver variedades de alto rendimento.

Statistical modeling for analyzing grain yield of durum wheat under rainfed conditions in Azad Jammu Kashmir, Pakistan / Modelagem estatística para analisar o rendimento de grãos de trigo durum sob condições de chuva em Azad Jammu Kashmir, Paquistão

One of the most important traits that plant breeders aim to improve is grain yield which is a highly quantitative trait controlled by various agro-morphological traits. Twelve morphological traits such as Germination Percentage, Days to Spike Emergence, Plant Height, Spike Length, Awn Length, Tillers/Plant, Leaf Angle, Seeds/Spike, Plant Thickness, 1000-Grain Weight, Harvest Index and Days to Maturity have been considered as independent factors. Correlation, regression, and principal component analysis (PCA) are used to identify the different durum wheat traits, which significantly contribute to the yield. The necessary assumptions required for applying regression modeling have been tested and all the assumptions are satisfied by the observed data. The outliers are detected in the observations of fixed traits and Grain Yield. Some observations are detected as outliers but the outlying observations did not show any influence on the regression fit. For selecting a parsimonious regression model for durum wheat, best subset regression, and stepwise regression techniques have been applied. The best subset regression analysis revealed that Germination Percentage, Tillers/Plant, and Seeds/Spike have a marked increasing effect whereas Plant thickness has a negative effect on durum wheat yield. While stepwise regression analysis identified that the traits, Germination Percentage, Tillers/Plant, and Seeds/Spike significantly contribute to increasing the durum wheat yield. The simple correlation coefficient specified the significant positive correlation of Grain Yield with Germination Percentage, Number of Tillers/Plant, Seeds/Spike, and Harvest Index. These results of correlation analysis directed the importance of morphological characters and their significant positive impact on Grain Yield. The results of PCA showed that most variation (70%) among data set can be explained by the first five components. It also identified that Seeds/Spike; 1000-Grain Weight and Harvest Index have a higher influence in contributing to the durum wheat yield. Based on the results it is recommended that these important parameters might be considered and focused in future durum wheat breeding programs to develop high yield varieties.

Uma das características mais importantes que os produtores de plantas visam melhorar é o rendimento de grãos, que é uma particularidade altamente quantitativa e controlada por várias características agromorfológicas. Foram considerados 12 traços morfológicos como fatores independentes, como Porcentagem de Germinação, Dias para Emergência da Espiga, Altura da Planta, Comprimento da Espiga, Comprimento da Aresta, Perfilhos /Planta, Ângulo da Folha, Sementes /Espiga, Espessura da Planta, Peso de 1000 Grãos, Índice de Colheita e Dias até a Maturidade,. A correlação, regressão e análise de componentes principais (em inglês Principal Component Analysis (PCA)) são usadas para identificar as diferentes características do trigo duro, que contribuem significativamente para o rendimento. As suposições necessárias exigidas para a aplicação da modelagem de regressão foram testadas e todas as suposições são adequadas de acordo com os dados observados. Os outliers são detectados nas observações de características fixas e rendimento de grãos. Algumas observações são detectadas como outliers, mas as observações outliers não mostraram qualquer influência no ajuste da regressão. Para selecionar um modelo de regressão parcimonioso para o trigo duro, foram aplicadas tanto a melhor regressão de subconjunto quanto as técnicas de regressão stepwise. A melhor análise de regressão de subconjunto revelou que a porcentagem de germinação, perfilhos /planta e sementes /espiga tem um efeito de aumento acentuado, enquanto a espessura da planta tem um efeito negativo sobre o rendimento do trigo duro. Enquanto a análise de regressão passo a passo identificou que as características, porcentagem de germinação, perfilhos/planta e sementes /espiga contribuem significativamente para aumentar a produtividade do trigo duro. O coeficiente de correlação simples especificou a correlação positiva significativa do rendimento de grãos com a porcentagem de germinação, número de perfilhos/planta, sementes / espiga e índice de colheita. Esses resultados da análise de correlação direcionaram a importância dos caracteres morfológicos e seu impacto positivo e significativo no rendimento de grãos. Os resultados da PCA mostraram que a maior parte da variação (70%) entre o conjunto de dados pôde ser explicada pelos cinco primeiros componentes. Também identificou que Sementes / Espiga, Peso de 1000 Grãos e Índice de Colheita têm uma maior influência na contribuição para o rendimento do trigo duro. Com base nos resultados, recomenda-se que esses importantes parâmetros possam ser considerados e focados em futuros programas de melhoramento de trigo duro para desenvolver variedades de alto rendimento.

Statistical modeling for analyzing grain yield of durum wheat under rainfed conditions in Azad Jammu Kashmir, Pakistan.

One of the most important traits that plant breeders aim to improve is grain yield which is a highly quantitative trait controlled by various agro-morphological traits. Twelve morphological traits such as Germination Percentage, Days to Spike Emergence, Plant Height, Spike Length, Awn Length, Tillers/Plant, Leaf Angle, Seeds/Spike, Plant Thickness, 1000-Grain Weight, Harvest Index and Days to Maturity have been considered as independent factors. Correlation, regression, and principal component analysis (PCA) are used to identify the different durum wheat traits, which significantly contribute to the yield. The necessary assumptions required for applying regression modeling have been tested and all the assumptions are satisfied by the observed data. The outliers are detected in the observations of fixed traits and Grain Yield. Some observations are detected as outliers but the outlying observations did not show any influence on the regression fit. For selecting a parsimonious regression model for durum wheat, best subset regression, and stepwise regression techniques have been applied. The best subset regression analysis revealed that Germination Percentage, Tillers/Plant, and Seeds/Spike have a marked increasing effect whereas Plant thickness has a negative effect on durum wheat yield. While stepwise regression analysis identified that the traits, Germination Percentage, Tillers/Plant, and Seeds/Spike significantly contribute to increasing the durum wheat yield. The simple correlation coefficient specified the significant positive correlation of Grain Yield with Germination Percentage, Number of Tillers/Plant, Seeds/Spike, and Harvest Index. These results of correlation analysis directed the importance of morphological characters and their significant positive impact on Grain Yield. The results of PCA showed that most variation (70%) among data set can be explained by the first five components. It also identified that Seeds/Spike; 1000-Grain Weight and Harvest Index have a higher influence in contributing to the durum wheat yield. Based on the results it is recommended that these important parameters might be considered and focused in future durum wheat breeding programs to develop high yield varieties.

Operative procedures in the elderly in low-resource settings: a review of Médecins Sans Frontières facilities.

BACKGROUND: As the demographic transition occurs across developing countries, an increasing number of elderly individuals are affected by disasters and conflicts. This study aimed to evaluate the elderly population that underwent an operative procedure at MSF facilities. METHODS: A retrospective review of prospectively collected operative cases performed at MSF-Operational Centre Brussels (MSF-OCB) facilities between June 2008 and December 2012 was completed. Baseline demographic data, American Society of Anesthesiologists (ASA) physical status and surgical indications were collected for each patient. For each procedure, the degree of urgency, anesthesia type, and intra-operative mortality were noted. All patients aged 50 and over at the time of the procedure were considered elderly, as proposed by the World Health Organization (WHO). Comparisons were made with the 18-49 age group in order to elucidate differences between older and younger individuals. RESULTS: We reviewed a total of 93,385 procedures performed on 83,911 patients in 21 different countries. Patients aged 50 and over comprised 11.5% (9,628/83,911) of all patients. While most procedures (57.6%) in the comparison group were urgent, this proportion decreased substantially in the elderly. Intra-operative mortality was considerably lower in the 50-59 group (0.12%) but increased with each age stratum. The most commonly performed surgical procedures in the elderly included herniorrhaphies, simple and extensive wound debridements, abscess incision and drainages, minor tumorectomies, and urological procedures. CONCLUSIONS: In light of the increasing elderly population in developing countries, efforts should be made to better quantify and address their surgical needs.

Modulation of small intestinal nitric oxide synthase by gum arabic.

Preceding studies have revealed that gum arabic (GA), a natural proteoglycan (>/= 250,000 Da), has proabsorptive properties-as shown by increased sodium and water absorption-in normal rats, and especially in two animal models of diarrhea. Because nitric oxide (NO) metabolism is linked to gastrointestinal physiology, the goals of this study were to determine whether GA modulated NO and to determine intestinal function in vivo when NO production was enhanced by l-arginine (Arg), added at either 1 or 20 mM. Mechanistically, the goal was also to determine whether GA was a NO scavenger and a small intestinal NO synthase (NOS) inhibitor. Using a glucose-electrolyte solution in rat jejunal perfusions we found that GA at +/-10 microM (2.5 g/l) decreased nitrite and nitrate formation, tending to normalize water, sodium, and glucose absorption when modified by Arg addition. In vitro tests, with oxyhemoglobin as a marker, showed that GA at >/= 5 microM scavenged NO. For GA effects on NOS, small intestinal homogenate supernatants (10,000 g) from frozen tissues of either adult or 2-day-old rats were incubated for 1 hour at 37 degrees C in the presence of 2 mM Arg and increasing GA concentrations (0-100 microM). GA produced a concentration-dependent inhibition of NOS, reaching approximately 31% inhibition with 5 microM GA and up to 51% with 50 microM GA. GA at 100 microM produced no further inhibition. The data indicate that GA, in addition to its ability to remove NO diffused into the intestinal lumen, may also partially inhibit intestinal NOS and thus modulate intestinal absorption through these mechanisms. Use of GA as a food additive may help in restoring or improving small intestinal function in conditions where functional damage has occurred.

Gum arabic (GA) modifies paracellular water and electrolyte transport in the small intestine.

Previous experiments have shown that a soluble fiber, gum arabic (GA), enhances water, electrolyte, and glucose absorption in animal models of diarrhea. The mechanisms implicated in this effect have not been fully elucidated. This study examined the possibility that paracellular transport is modulated by luminal GA, resulting in an enhanced rate of absorption in the small intestine. This hypothesis was tested by 3-hr jejunal perfusions on anesthetized rats with solutions containing 140 mM NaCl, 5 mM KCl, and 2 microCi/liter (74 kBq) 3H2O, with either 2.5 g/liter GA [+GA] or in its absence [CTL], and one of the following agents, capable of altering paracellular transport: chenodeoxycholic acid at 0.5 mM (CDC), 2,4,6-triaminopyrimidine (TAP) at 20 mM, and protamine at 100 mg/liter (PTM). Sodium, potassium, net water, and unidirectional water movement were measured. The addition of GA increased sodium absorption in perfusions with CDC, TAP, or PTM only. Similar effects by GA on net water absorption rates were obtained in tissues permeabilized with CDC and PTM; however, GA added to TAP did not normalize the reduction caused by TAP. Although PTM did not alter net water absorption, addition of GA to perfusates with PTM enhanced absorption values above those of CTL. GA reversed the strong negative effects of CDC on potassium absorption but was ineffective in this regard with TAP and PTM. The data obtained with those reagents that affect paracellular transport and the histological evidence support the view that GA promotes net absorption by this route in the small intestine of normal rats.

Zinc as a potential enteroprotector in oral rehydration solutions: its role in nitric oxide metabolism.

Zinc has been recognized as an antioxidant with potential for chronic and acute effects. Oxidative damage produced by free radicals, including nitric oxide (NO), is responsible for certain types of intestinal malabsorption syndromes and diarrhea. Under physiologic or mildly stimulatory conditions for NO synthesis, the small intestine characteristically is in a proabsorptive state; however, an excessive production of NO triggers formation of cyclic nucleotides, which cause secretion and malabsorption. In this study, we hypothesized that low-molecular-weight, soluble zinc chelates could modulate the effects of induced NO excess on the small intestine. In vitro experiments demonstrated that zinc-citrate or zinc-histidine at > or =0.66 mM, as well as a known NO scavenger, 2-[carboxyphenyl]-4,4,4,4-tetramethylimidazoline-1-oxyl-3-oxide, at 2 microM, were effective at removing chemically generated NO. In vivo jejunal perfusions, conducted in healthy rats under anesthesia, showed that c-PTIO reduced the proabsorptive effects produced by 1 mM L-arginine, the precursor of NO. In a standard oral rehydration solution, 1 mM zinc-citrate partially reversed the antiabsorptive effects on potassium caused by an excess of NO generated from 20 mM L-arginine but did not alter sodium or water absorption. The data are consistent with the view that soluble zinc compounds incorporated into an oral rehydration solution may deserve further attention as a means to scavenge NO with fluids used for the treatment of chronic or acute diarrhea, especially in malnourished children who are often zinc deficient.

Neonatal outcome of infants born at 500 to 800 grams from 1990 through 1998 in a tertiary care center.

OBJECTIVE: To assess if there have been changes in survival, demographic data, obstetric features, neonatal morbidity, and short-term neurologic/radiographic/neurosensory outcome of 500- to 800-g infants born in a tertiary care neonatal center from 1990 through 1998. STUDY DESIGN: Records of all 500- to 800-g infants born at North Shore University Hospital during 1990-1998 were reviewed to determine demographic data, survival by weight and gestational age (GA), obstetric features, neonatal morbidity, and short-term neurologic/radiographic/neurosensory outcome. Newborn infants were grouped into three triennia: 1990-1992, 1993-1995, and 1996-1998 and compared across time. RESULTS: Of the 173 infants admitted to the neonatal intensive care unit, 112 survived. Improved survival was documented: 40% in 1990-1992, 73% in 1993-1995, and 81% in 1996-1998 (p < 0.0001). Improved survival was also noted in each of the three weight cohorts, as well as in infants < or =26 weeks GA. An increased use of antenatal corticosteroids and increased number of deliveries by cesarean section (C/S) were noted across time. The incidence of 0 to 3 Apgar scores at both 1 and 5 minutes decreased across time. Necrotizing enterocolitis in survivors and expected short-term neurologic/radiographic/neurosensory outcome improved between 1990-1992 and 1996-1998, with a trend toward reduced IVH grade III to IV. The incidence of other neonatal morbidities did not change throughout the time period. CONCLUSIONS: The data document that survival rates continued to improve for 500- to 800-g infants throughout the 1990s. This was concurrent with an increase in "low-risk, expected normal" infants, increased number of deliveries by C/S, decreased incidence of low Apgar scores at both 1 and 5 minutes, and an increased use of antenatal corticosteroids.

Zinc supplementation in oral rehydration solutions: experimental assessment and mechanisms of action.

BACKGROUND: Zinc deficiency is associated with chronic diarrhea. This condition is generally linked to an overproduction of nitric oxide (NO), which induces secretion and cellular damage as a free radical. Use of oral rehydration solutions (ORS) is an important part of diarrhea treatment, especially early in infancy and for patients with cholera. The presence of zinc in an ORS could be a positive factor in recovery from diarrheal disease. OBJECTIVE: This study was undertaken to determine whether zinc added to an ORS could regulate the synthesis of NO metabolites in the lumen of zinc deficient rat intestine, acting as a gastrointestinal protector and thus accelerating normalization of intestinal function and zinc status. METHODS: The effects of zinc on NO metabolism were studied in young male rats fed a zinc deficient diet for three weeks to mimic the condition of patients with recurrent diarrheal episodes. During the fourth week of the zinc deficient feedings, experimental diarrhea was induced using cathartics (magnesium citrate plus phenolphthalein) that exacerbate NO production. A standard ORS with or without 1 mM zinc was given to the rats for the last two days. A control group received a zinc sufficient diet. Rats were killed at each stage. Intestinal nitric oxide synthase (NOS) was assayed, cecal fluid contents were analyzed for nitrates and nitrites, intestinal histology was examined, and activation of nuclear factor NF-kappaB DNA binding activity was determined. RESULTS: Rats fed the zinc-deficient diet for three weeks gained less weight than rats fed a normal zinc content diet and had a lower plasma zinc than controls (51.6 +/- 5.4 [n = 101 vs. 143.6 +/- 7.2 microg/dL [n = 11], p < 0.05). Recovery with ORS+Zn resulted in a higher plasma zinc than with the ORS-Zn (ORS+Zn: 186.5 +/- 12.2; ORS-Zn: 57.5 +/- 6.6 microg/dL, p < 0.05). The zinc-deficient diet did not alter mucosal NOS, as compared to the values of rats fed a normal diet. However, those animals which received five days of cathartic fluids had a small intestinal NOS higher than that of all other groups. Either ORS+Zn or ORS-Zn normalized NOS activity, regardless of cathartic treatment. The rats fed the zinc deficient diet had generally a higher content of NO metabolites in the cecum than rats fed a normal diet. After recovery with either type of ORS, rats given the cathartic remained with higher cecal NO metabolite concentrations than rats that had no induced diarrhea. After recovery with ORS+Zn, intestinal villi showed significant expansion of the lamina propria, an indication of greater absorption of fluid, while with ORS-Zn this was not present. Small intestinal homogenates of rats recovering with ORS+Zn had a decreased NF-kappaB DNA binding activity than tissues from rats consuming ORS-Zn. CONCLUSIONS: The results are consistent with the hypothesis that addition of Zn to an ORS may contribute to improving the physiologic status of the small intestine and potentially reduce the risks of recurrent diarrhea episodes.