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Sorgo como fonte de carboidrato em alimentos extrusados para gatos : uso de diferentes variedades e moagens e efeitos sobre a digestibilidade, produtos de fermentação, imunidade intestinal e microbiota /Ribeiro, Érico de Mello. January 2020 (has links)
Orientador: Aulus Cavalieri Carciofi / Resumo: O objetivo deste estudo foi avaliar o efeito de duas variedades de sorgo, processadas diferentemente, na palatabilidade, digestibilidade dos nutrientes, produtos de fermentação fecal e microbiota em gatos adultos. Quatro dietas com composições similares foram formuladas com milho (Mi), arroz integral (AI), sorgo vermelho (SV) ou sorgo branco (SB) como principal fonte de carboidrato. As dietas Mi e AI foram moídas apenas com peneira de 1,0 mm (média), enquanto que as dietas SV e SB foram moídas com peneiras de 0,8 mm (fina), 1,0 mm e 1,6 mm (grossa), totalizando oito dietas. O experimento foi delineado em blocos casualizados, com quatro blocos de 16 gatos, dois gatos por dieta em cada bloco, totalizando oito repetições por tratamento e 64 unidades experimentais. Após o período de adaptação, a digestibilidade dos nutrientes foi calculada pelo método de coleta fecal total e o escore fecal foi avaliado. Amostras fecais frescas foram coletadas para análise dos produtos de fermentação, medição do pH, aminas biogênicas e microbiota. Valores de P <0,05 foram considerados significativos. A palatabilidade foi maior nas dietas SV e SB na moagem média do que nas dietas Mi e AI (P <0,01), e a dieta SB apresentou maior consumo que SV (P <0,05). Para a dieta SV, a maior granulometria apresentou melhor consumo do que a menor granulometria (P <0,05). Não houve diferença significativa na digestibilidade aparente dos nutrientes entre as dietas, exceto uma redução na digestibilidade da matéria s... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this study was to evaluate the effect of two sorghum varieties, processed differently, on palatability, nutrient digestibility and fecal fermentation products in adult cats. Four diets with similar compositions were formulated with corn (C), brown rice (BR), red sorghum (RS) or white sorghum (WS) as the main carbohydrate source. The C and BR diets were ground with 1.0 mm (medium) screen sieve; RS and WS were ground with sieve sizes of 0.5 mm (fine), 1.0 mm and 1.6 mm (coarse) each, totaling eight diets. The experiment was a randomized complete block design with four blocks of 16 cats, two cats per diet in each block, totaling eight replicates per treatment and 64 experimental units. After the adaptation period the nutrient digestibility was calculated by the total fecal collection method and the fecal score was evaluated. Fresh fecal samples were collected for analysis of fermentation products, pH measurement, biogenic amines and microbiota. Values of P <0.05 were considered significant. Palatability was higher for RS and WS diets at medium particle size than C and BR diets (P <0.01) and WS presented higher intake than RS (P <0.05). For RS, bigger particle size had better consumption than small particle size (P <0.05). There were no differences in apparent digestibility of the nutrients between the diets, except lower DM for WS with bigger particle size (P = 0.007). Fecal production, score and ammonia were similar between diets (P> 0.05). Fecal pH was lower a... (Complete abstract click electronic access below) / Doutor
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Vegetative propagation of Pappea capensis Eckl.&Zeyh. (Jacket plum) by means of stem cuttings and air layersRafiri, Matumelo Alice 01 September 2011 (has links)
Jacket plum [ Pappea capensis ( Eckl.&Zeyh)] belongs to the Sapindaceae or Litchi family. It is well adapted to different climatic conditions. It has been used for medicinal purposes for both animals and human beings. Due to the richness of seeds in oil, it has great potential to be selected for production of biodiesel in South Africa. Suitable vegetative propagation methods for Pappea capensis trees have not yet been investigated and sexual propagation does not produce true-to-type plants, which take many years to bear fruits. Therefore, research was carried out to identify alternative methods for vegetative propagation of Pappea capensis which could be used for rapid multiplication. Several vegetative propagation experiments were carried out with stem cuttings and air layers. Stem cuttings were collected from two mature Pappea capensis trees grown at the Experimental Farm of the University of Pretoria in the spring and autumn seasons. The cuttings were placed for rooting on the mist bed for rooting with and without Seradix® No. 2 [active ingredient, indolebutyric acid (IBA)] treatment. Other experiments followed in which the branches were girdled before making stem cutting to improve the level of any carbohydrates or available carbohydrates. Trials to investigate the rooting potential of Pappea capensis coppices, using different stem lengths, were also conducted. Rooting of Pappea capensis stem cuttings was unsuccessful. Air layers were made on the same trees where cuttings were collected. The trials were conducted in the spring and autumn seasons from 2006, 2007 and 2008. Some air layers were treated with Seradix® No. 2 and others were not treated with the auxin. High rooting percentages (100% in spring, 60% in autumn) were achieved with untreated air layers of Tree No. 1 and Tree No. 2 (80% in spring, 40% in autumn). Regardless of season, IBA and tree treatments, rooting was successful when the air layering method was used. Due to inconsistency in rooting from both vegetative methods, total phenolic compounds were extracted. The Folin-Ciaocalteau reagents method was used to extract phenolic compounds and the results were detected with Elisa reader instrument. The stem cuttings and air layers were further analysed for carbohydrates (starch and soluble sugars) with ó-toluidine reagent and ethanol and read with Spectrophotometer and high performance liquid chromatography (HPLC). Higher levels of total phenol compounds were observed from callused (27.13 mg/g) and non rooted untreated (26.41 mg/g) stem cuttings from Tree No. 2, compared to IBA treated stem cuttings (19.90 mg/g) of callused and non rooted IBA treated stem cuttings (20.25 mg/g) of Tree No. 2. High total phenols (34.55 mg/g) in untreated air layers were also found in callused air layers of Tree No. 2 and lower amounts (22.85 mg/g) in treated air layers of the same tree. No soluble sugars were detected in stem cuttings or air layers with HPLC. Regarding starch, higher amounts were observed in stem cuttings of Tree No. 1 (18.45 mg/g) of the control and Tree No. 2 (19.82 mg/g) of IBA treated cuttings. Most of the air layers made on Tree No. 1 had higher percentages of starch, with the exception of the callused (7.41 mg/g) air layers of the control. Tree No. 2 air layers had very low amounts of starch when compared with those of Tree No. 1. The variation in rooting potential of stem cuttings and air layers led to the consideration of tree gender as a factor influencing success rates, where inflorescences were collected from the two Pappea capensis trees for two years (2007 and 2008). The microscopic investigations showed that Pappea capensis trees (Tree No. 1 and Tree No. 2) were monoecious, however, Tree No. 2 switched from monoecious to male by producing only male flowers. Based on the results of the above investigations, air layering in the spring season can be used as a (alternative) vegetative propagation method for Pappea capensis tree, but on specifically monoecious tree to obtain higher rooting percentage. However, these are preliminary trials which require further investigation. / Dissertation (MSc(Agric))--University of Pretoria, 2010. / Plant Production and Soil Science / unrestricted
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EXPERIMENTAL AND CLINICAL INVESTIGATIONS OF SLOWLY DIGESTIBLE CARBOHYDRATES FOR IMPROVED PHYSIOLOGICAL OUTCOMES AND METABOLIC HEALTHPablo C Torres Aguilar (12473172) 29 April 2022 (has links)
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<p>The world has experienced an unprecedented change in the systems responsible for food production, distribution, and commercialization with concurrent changes in diets. In developed and developing countries, the shift in consumption patterns has moved towards a Western diet pattern which has been linked to negative health outcomes including obesity, diabetes and associated non-communicable diseases. Traditional African diets have previously been associated with protective effects against the development of the above-mentioned conditions. Yet, the underlying reasons for this is not clear. One dietary factor that may contribute to its protective effect is the principal available carbohydrate, starch, which in traditional African staples is considered to contain slowly digestible carbohydrates (SDCs) and some amount of resistant starch (RS). We reported that traditional African staple starchy foods (sorghum and millet) had markedly slower gastric emptying than introduced modern starchy foods (rice, pasta and potatoes). This response was attributed to activation of enteroendocrine cells of the small intestine (L-cells) with potential to trigger physiological, hormonal, and neurological processes that affect digestion time and perception of hunger; effect known as the ileal brake. Moreover, at least in mice models, consumption of SDCs has shown to have beneficial effects on the rate and type of fuel (e.g. carbohydrate vs fat) used for metabolic processes.</p>
<p>The first thesis study compared the effect of diets (cohorts in the USA and Kenya) on gastric half-emptying time and metabolic fuel utilization in healthy adults. Our findings showed that gastric emptying time was not different between cohorts and that diet did not influence gastric emptying time; however, calculated respiratory exchange ratio (RER) (which is a measure of metabolic fuel utilization at the cellular level, e.g. carbohydrate vs fat) and metabolic flexibility (which is the ability to switch between metabolic fuel sources upon demand or need) was higher for the Kenyan cohort. Multivariant models were developed and corrected for multicollinearity of some diet variables. Carbohydrate and protein in multivariate model 1; total fiber, added sugars and starch in multivariate model 2; and diet quality (measured as the Healthy Eating Index based on 2015-2020 dietary guidelines, or HEI-2015) in multivariate model 3, were significantly and independently correlated with RER and metabolic flexibility. </p>
<p>The second study assessed if slow gastric emptying and improve metabolic fuel utilization could be induced through SDC supplementation. The objective of this study was to determine if continual consumption of SDC for 21 days delayed the rate of gastric emptying, moderated postprandial glycemic response, decreased hunger, and/or improved metabolic fuel utilization in subjects with low diet quality (HEI-2015<65). Our results indicated that supplementation with SDC did not slow gastric emptying time or acute measures of metabolic fuel utilization; however, continuous consumption of SDC had a modest but significant effect on improving metabolic flexibility and decreasing hunger scores. </p>
<p>The last two chapters of this thesis focused on the use of a low-cost, high-pressure, high temperature extruder suitable for processing in Africa of whole grain pearl millet (<em>Pennisetum glaucum</em>). In Africa, emerging, entrepreneurial companies are increasingly gaining share of local markets by manufacturing and distributing high-quality locally sourced processed foods made with indigenous grains. Whole pearl millet is particularly susceptible to development of rancidity. The objective of our third study was to assess the use of the extruder on the stability and sensory attributes of whole grain pearl millet extruded flours to be used for instant thin and thick porridges. Findings showed that extrusion fully gelatinized the starch in pearl millet and prevented hydrolytic rancidity in the instant flour products. However, extrusion cooking did not stop oxidative rancidity. We concluded that while extrusion cooking is a versatile technology for whole grain processing, refinement of extrusion conditions used in the experiment and the evaluation of other unit operations (e.g. steeping, germination) in combination with extrusion cooking may improve the sensory properties of final products.</p>
<p>Finally, extrusion cooking has been showed to promote the formation of beneficial amylose-lipid complexes (ALCs). The objective of the last study was to evaluate the formation of ALCs in whole grain pearl millet extruded flours, characterize their composition, and assess their ability to slowly digest <em>in vitro</em>. Extrusion promoted the formation ALCs and these flours exhibited a slow enzymatic digestion <em>in vitro</em>. The findings from this thesis provide insights into the role of diets and metabolic fuel utilization, and improvement of processed pearl millet foods in Africa.</p>
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Quality of life is higher in type 1 diabetes patients with smaller glycemic excursions and glycemic excursions are smaller when carbohydrate intake ratio is higher. / 1型糖尿病患者の生活の質は血糖変動が小さいほど高く、血糖変動は食事中の炭水化物割合が高いほど小さくなる。Ayano, Shiho 24 November 2015 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第12968号 / 論医博第2101号 / 新制||医||1012(附属図書館) / 32406 / 新制||医||1012 / 京都大学大学院医学研究科医学専攻 / (主査)教授 長船 健二, 教授 福原 俊一, 教授 川口 義弥 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
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Synthesis of Phosphonate Analogues of the Antibiotic Moenomycin A12Abu Ajaj, Khalid 18 December 2002 (has links)
SUMMARY The moenomycin-type compounds are known to inhibit selectively the enzyme penicillin binding protein 1b (PBP 1b) that catalyses the transglycosylation reaction in the biosynthesis of bacterial cell wall peptidoglycan. The moenomycins (see moenomycin A12) have been shown to interfere with this biosynthetic step interacting with the enzyme(s). The moenomycins do not induce resistance readily. A weak point in this respect may, however, be the phosphate bond to unit F. Its cleavage by a yet poorly characterized enzyme is the only enzymatic degradation reaction of the moenomycins that is known to-date. With this in mind we started a programme aimed at synthesizing trisaccharide analogues of moenomycin A12 in which the phosphate oxygen at C-1 of unit F is replaced by a CH2 group. It seemed important to retain all other functional groups in ring F as present in moenomycin since they are known to be of major importance as far as antibiotic activity is concerned. It appeared that the commercially available and cheap b-D-galactose-pentaacetate 30 would be an interesting starting material for this synthesis. In this work, the synthesis began with the introduction of the C-glycoside appendage at position 1 according to Giannis et al., thus forming the allyl C-galactopyranoside 34, a substance that represents the first C-glycosyl backbone for the synthesis of the glycosyl acceptors. The total synthesis of the glycosyl acceptors is shown in Scheme 6.1. We wanted to convert the C-allyl glycoside 34 into its propenyl analogue. Attempts to achieve this with singlet oxygen and palladium-mediated reaction proved fruitless. On the other hand, ene reaction of 34 with 4-phenyltriazolin-3,5-dione in CH2Cl2 provided 56 in 83 % yield. Ozonolysis of this alkene (-70 °C, MeOH-CH2Cl2) and subsequent quenching with dimethyl sulfide, followed by reduction of the crude aldehyde with sodium acetoxyborohydride (prepared from NaBH4 and AcOH in THF) furnished the primary alcohol 35 (85 %). This alcohol was converted into the mesylate 60 (60 %), and this in turn into the bromide 61 (80 %) by heating it at 80 °C with tetrabutylammonium bromide in toluene. The acetate groups were hydrolysed using Zemplén conditions to furnish 62 quantitatively. The primary hydroxyl group in 62 was protected as a tBuPh2Si ether 63 (85 %) on reaction with TBDPSCl in DMF at 0 °C, and as a tBuMe2Si ether 94 (87 %) on reaction with TBDMSCl in DMF at 0 °C in the presence of imidazole. PTScatalysed isopropylidenation of the 3,4-diols 63 and 94 with 2,2-dimethoxypropane in dry acetone gave the 3,4-O-acetonide derivatives 53 (88 %) and 95 (90 %), respectively. On the other hand, the glycosyl acceptor 53 was converted into the glycosyl acceptor 92. The free hydroxyl group in compound 53 was protected as an acetate group on reaction with acetic anhydride in pyridine in the presence of DMAP giving 89 (88 %). The silyl ether in 89 was cleaved with a molar solution of TBAF in THF affording compound 90 in 87 % yield. The free hydroxyl group in 90 was then subjected to an oxidation using the TEMPO method affording the aldehyde which was in turn oxidised with sodium chlorite to the corresponding acid. The acid was converted to the amide 91, making use of Staab''s method, in which the acid was activated with CDI in dichloromethane to give the imidazolide, which upon reaction with ammonia furnished the amide 91 in an overall yield of 95 %. The required glycosyl acceptor 92 was obtained in quantitative yield by cleavage of the ester bond at position 5 under Zemplén conditions. Disaccharide formation was achieved employing the Jacquinet and Blatter method, which involves the use of glycosyl donor 67 and TMSOTf. No reaction was observed between this donor and acceptor 92, which may reflect the low nucleophilicity of the acceptor. On the contrary, glycosylation with acceptor 53 gave 68 (79 %). Deprotection of the silyl group in the disaccharide 68 was easily accomplished on treatment with a molar solution of TBAF in THF at RT affording 71 (89 %). Synthesis of the uronamide 72 was achieved after three major steps, in an overall yield of 98 %. Oxidation of the primary hydroxyl group in unit F to the corresponding aldehyde was accomplished with sodium hypochlorite and TEMPO. Oxidation of the crude aldehyde to the carboxylic acid with sodium chlorite followed by amide formation according to Staab gave 72. Removal of the isopropylidene group from 72 with trifluoroacetic acid (TFA) at RT furnished the diol 73 (89 %). Introduction of the carbamoyl group at C-4F position was achieved in two steps. Conversion of the diol 73 into the cyclic carbonate 76 with CDI in CH2Cl2 (84 %) and subsequent ring opening of this carbonate by bubbling a stream of gaseous ammonia into the CH2Cl2 solution at 0 °C gave 74 (62 %) as well as its isomer 77 (21 %). Dehalogenation of the N-trichloroacetyl group was intensively studied, but interactions of other functional groups in the studied substances could not be avoided. The base-labile carbonate in 76 and the carbamoyl group in urethane 74 were cleaved under the reaction conditions. Hydrolysis of 76 with 0.5 M LiOH in MeOH-THF (1:1) followed by acetylation gave 80 (73 %), while its reduction with NaBH4 in ethanol followed by acetylation gave 82 (60 °C, 85 %; RT, 83 %). On the other hand, reduction of 74 with NaBH4 in ethanol at 60 °C followed by acetylation gave 82 (78 %), while performing the reduction step at 5 °C (THF-MeOH 4:1) or at RT (ethanol or isopropanol) gave 80 in an average yield of 65 %. In a non reproducible reaction (NaBH4, EtOH, RT, then Ac2O, pyridine, RT), the desired compound 83 (42 %) was obtained accompanied by 82 (46 %) The reaction between the N-trichloroacetyl group and NaBH3CN was also fruitless. The phosphonate grouping was installed making use of Arbuzov reaction furnishing 85 (70 %). Trisaccharides could not be obtained from the oxazoline donor 42 (prepared from chitobiose octaacetate 86) through its reaction with acceptor 53. There was also no coupling product between the recently synthesized donor 88 and the acceptor 92. However, in this work, trisaccharide formation was achieved through the glycosylation reaction of donor 88 and acceptor 95 in 50 % yield (-30 °C, 1,2-dichloroethane, 3 Å, TMSOTf-TEA). Selective deprotection of the TBDMS group in compound 96 was accomplished at -10 °C with 1 eq of a molar solution of TBAF in THF. The free hydroxyl group of 97 was subjected to an oxidation using the TEMPO method affording the aldehyde. After oxidation of the aldehyde with sodium chlorite, the resulting carboxylic acid was converted according to Staab''s method into the amide 93 in an overall yield of 95 % (based on 96). There were difficulties in converting the N-phthalimido group in 93 to the N-acetyl group which is necessary for biological activity of moenomycin-type compounds, since the reactions were accompanied by elimination of HBr. In conclusion, the synthetic methods employed in this work allow to prepare the di- and trisaccharides C-phosphonate analogues of moenomycin A12. / Synthese von Phosphonat-Analoga des Antibiotikums Moenomycin A12 Universität Leipzig, Dissertation Diese Arbeit enthält 130 Seiten, 73 Abbildungen, 1 Tabelle, 156 Literaturangaben Referat: Im Rahmen der vorliegenden Arbeit wurden C-Glycosid-Di- und Trisaccharid-Bausteine des Antibiotikums Moenomycin A12 ausgehend von b-D-Galactose-pentaacetat hergestellt. Das Ausgangmaterial wurde in D-Galactoheptonamid übergeführt. Die Einheit F des Disaccharidbausteins hat alle Substituenten, die die Einheit F des Moenomycins A12 hat. Der ausgearbeitete Syntheseweg sollte zur Synthese anderer Analoga geeignet sein.
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Determination of Lactose by Reversed-Phase High Performance Liquid Chromatography.Sexton, Danessa Leann 01 May 2004 (has links) (PDF)
Lactose is the common disaccharide found in dairy products. It can, however, be a source of discomfort for those whom are lactose intolerant. Therefore, it is necessary to accurately, reliably, and efficiently determine the lactose content of foods. The goal of this research was to develop a reversed-phase HPLC method with UV detection for the determination of lactose. Aminobenzoic acid was used to prepare a derivative, making detection possible in the 300-360 nm region. The stationary phase is a C8 column, with 85% methanol 15% water mixture at pH 5 as the mobile phase. A linear response of peak area to lactose concentration of 0.018 mg/mL to 0.36 mg/mL was obtained with an estimated detection limit of 0.0036 mg/mL lactose concentration. The reproducibility was established with a 4.95% relative standard deviation. The average recovery was 107%, and results were in strong agreement with the standard alkaline ferricyanide method, establishing accuracy.
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The Effect of Post Exercise Nutrition on Anabolic Response to Resistance ExerciseBird, Randy Lee 13 April 2005 (has links)
Purpose: To determine the effect of four postexercise beverages, differing in macronutrient content, on metabolic response to an acute resistance exercise bout.
Methods: Forty male subjects performed five sets of eight repetitions at 80% 1RM for leg press and leg extension, and then consumed one of four postexercise beverages (Placebo, PL: a carbohydrate-electrolyte beverage, CE; or one of two milk-based beverages, MILK 1: 1% chocolate milk; MILK 2: a high protein milk beverage). Indicators of muscle protein synthesis (MPS) were assessed before and 1-hr after consuming a postexercise beverage. Muscle protein degradation (MPD) was examined the day before and the day of exercise.
Results: No significant differences were found among groups in MPS. The resistance exercise bout increased the amount of eIF4E-eIF4G by 4.5% 1-hr postexercise (p<0.05) without affecting the amount of eIF4E-4E-BP1. One hour after beverage consumption, serum total amino acid concentration increased for MILK 1 (p=0.003) and MILK 2 (p<0.001) but decreased for CE (p=0.028) and PL (p=0.276). Consumption of MILK 1, MILK 2, and CE significantly increased circulating levels of serum insulin (p<0.001). Serum growth hormone increased 3-fold as a result of the exercise bout but fell to baseline for all groups by 60 min (p<0.001).
Conclusion: The resistance exercise bout was anabolic as shown by the increase in the active eIF4E-eIF4G complex and serum growth hormone. Consumption of MILK 2 led to the most optimal environment for muscle anabolism; however, none of the experimental beverages influenced the measured indicators of muscle protein translation 1-hr after ingestion. / Master of Science
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Use of Flame Cultivation as a Nonchemical Weed Control In Cranberry CultivationGhantous, Katherine M. 01 September 2013 (has links)
Cranberry (Vaccinium macrocarpon Ait.) is a woody perennial crop that can remain productive for decades. Competition for resources between cranberries and weeds can depress cranberry farm yields, resulting in large annual crop losses. Renewed interest in reducing chemical inputs into cranberry systems has provided the motivation to evaluate methods, such as flame cultivation (FC), as potential nonchemical options for weed control. Also known as thermal weeding, FC exposes plants to brief periods of high temperature that causes the water in the plant tissue to expand rapidly, rupturing plant cells and leading to necrosis. Various FC methods have been used successfully in annual crops as both a preemergence and postemergence weed control, but few scientific reports have been published on the use of FC on perennial weeds in a woody perennial crop system.
Dewberry (Rubus spp.), sawbrier (Smilax glauca), and common rush (Juncus effusus) are cranberry weeds that are difficult to control, spread quickly and can cause significant crop loss. Flame cultivation may be an effective non-chemical means for controlling these weeds in cranberry systems. FC would ideally be used as a spot treatment for weeds growing in the cranberry canopy, as well as on larger non-production areas where cranberry vines are not as abundant, such as bog edges, ditches, and dikes. Using FC to treat weeds within the cranberry canopy will likely cause localized damage to cranberry plants immediately surrounding the weeds, thus cranberry response to FC is also of interest.
The following experiments were designed to examine the response of weeds and cranberry plants to FC. Perennial plants rely on reserves of nonstructural carbohydrates (NSC) for growth and survival, thus the efficacy of FC treatments to weeds will likely be impacted by the timing and frequency of treatments as they relate to the specific carbohydrate cycles of targeted weeds, such as dewberry. An additional experiment studied the seasonal fluctuations of NSC in dewberry roots. Cranberry growers were also surveyed on their past experiences with FC, as well as their willingness to adopt FC if proven an effective method for controlling weeds.
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1-Bromo-1-lithioethene as a building block for organic synthesisNovikov, Yehor January 2005 (has links)
No description available.
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Impact of Bedtime Snack Consumption on Glycemic Control in Hospitalized Patients with DiabetesPalumbo, Stacy 06 December 2010 (has links)
No description available.
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