Optimization of harvest regime and post-harvest handling in geranium production to maximize essential oil yield in Rwanda     

Katarina MalatovaNicholas Hitimana  Theodor NiyibiziJames E. Simon  H. Rodolfo Juliani 《Industrial Crops and Products》2011,34(2):1348-1352

In Rwanda, the production of geranium (Pelargonium sp.) essential oil is becoming an important commercial crop for income generation. The understanding of postharvest handling of the crop prior to distillation is a key strategy to maximize oil yields. Two experiments were conducted in commercial fields of rose geranium, Pelargonium graveolens, in Kiyombe (Rwanda) to investigate the effects of (i) the length of dry-down or partial wilt and (ii) the time of day on the quantity and quality of essential oil yield and composition. In the first study, the plant material was harvested at 12:00 noon, and while drying also under the same shade conditions the material was sub-sampled immediately and again at 3 h intervals up through 46-h after harvesting. In the second study, the geranium plants were manually harvested at 10:00 AM, 12:00 noon, 2:00 PM, and 4:00 PM and dried under shade for 17 h prior to steam distillation. The geranium plants harvested in the early afternoon (2:00 PM) had the highest essential oil concentration (0.22%). The chemical profile of the essential oil showed that Kiyombe geranium oil exhibited a suitable chemical composition (citronellol 26.4%, linalool 2.3% and geraniol 13.9%), acceptable for international markets.  相似文献   

Associations between maternal employment and time spent in nutrition-related behaviours among German children and mothers     

Möser A  Chen SE  Jilcott SB  Nayga RM 《Public health nutrition》2012,15(7):1256-1261

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Effects of acaricides on Oligonychus sp. and compatibility with predatory mites Neoseiulus californicus and Phytoseiulus persimilis     

Cua-Basulto  Marcos E.  Ruiz-Sánchez  Esaú  Pérez-Gutiérrez  Alfonzo  Martín-Mex  Rodolfo  Nexticapan-Garcéz  Ángel  Pérez-Brito  Daisy 《植物病害和植物保护杂志》2021,128(6):1617-1625

Journal of Plant Diseases and Protection - In Mexico, outbreaks of phytophagous papaya mites (Oligonychus sp.) can threaten papaya production by damaging young leaves, causing a reduction in plant...  相似文献   

Strategies for the treatment of dairy cows at high risk for postpartum metritis and for the treatment of clinical endometritis in Argentina     

Julian A. Bartolome  Pablo Khalloub  Rodolfo Luzbel de la Sota  Marc Drillich  Pedro G. Melendez 《Tropical animal health and production》2014,46(1):79-85

The objectives of this study were to evaluate the efficacy of (1) administering ceftiofur hydrochloride in dairy cows with calving-related disorders to prevent metritis and (2) a combination of GnRH and PGF_2α for the treatment of clinical endometritis, under Argentinean dairy farming conditions. Cows at high risk (HRC) for metritis (dystocia, RFM >12 h postpartum, hypocalcaemia, twins, or stillbirth) were randomly assigned to receive either 1.1 mg/Kg of ceftiofur hydrochloride on three consecutive days (HRC treated group HRCT, n?=?110) or remained untreated (HRC control group HRCC, n?=?126). Cows with low risk (LRC, no calving-related disorders, n?=?868) did not receive any treatment (LRC group, n?=?868). All cows were examined for metritis between days 4 and 10 and for clinical endometritis between 24 and 30 days postpartum. The body condition score (BCS) was recorded at both examinations. Cows with endometritis at days 24 to 30 postpartum received either 1.5 mg of D-cloprostenol (PGF; n?=?129) or 100 μg of GnRH followed by D-cloprostenol after 7 days (GnRH+PGF, n?=?119). There was no overall effect of treatment on the incidence of metritis or on time to pregnancy. Treatment, however, reduced the incidence of metritis in cows with high BCS (HRCT?=?24.0 %, HRCC?=?38.5 %) but had no effect in cows with low BCS (HRCT?=?38.7 %, HRCC?=?37.5 %). The proportion of pregnant cows by days in milk was greater (P?<?0.01) in LRC group compared with that of the HRCT and HRCC groups. No significant differences were found between groups PG and PG+GNRH. GnRH+PGF treatment, however, tended (P?=?0.06) to increase pregnancy rate in cows with a moderate loss of BCS (76.5 vs 65.2 %) but tended to reduce pregnancy rate (54.5 vs 76.0 %) in cows with a more pronounced loss in BCS (>0.75 points).  相似文献   

Cross‐Sectional Anatomy,Computed Tomography and Magnetic Resonance Imaging of the Thoracic Region of Common Dolphin (Delphinus delphis) and Striped Dolphin (Stenella coeruleoalba)     

J. M. Alonso‐Farré  M. Gonzalo‐Orden  J. D. Barreiro‐Vázquez  J. M. Ajenjo  A. Barreiro‐Lois  M. Llarena‐Reino  E. Degollada 《Anatomia, histologia, embryologia》2014,43(3):221-229

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Acknowledgements to referees     

Asko Mäki‐Tanila  Rodolfo Cantet  Ignacy Misztal  Miguel Pérez‐Enciso  Henner Simianer  Julius van der Werf 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2014,131(6):536-536

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Evaluation of 1,2-O-dilauryl-rac-glycero glutaric acid-(6′-methylresorufin) ester (DGGR) and 1,2-diglyceride lipase assays in dogs with naturally occurring hypercortisolism     

Guido Linari  Francesco Dondi  Sofia Segatore  Kateryna Vasylyeva  Nikolina Linta  Marco Pietra  Rodolfo O. Leal  Federico Fracassi 《Journal of veterinary diagnostic investigation》2021,33(5):817

1,2-O-dilauryl-rac-glycero glutaric acid-(6′-methylresorufin) ester (DGGR) lipase activity has been proposed as a faster and less expensive test used in the diagnosis of acute pancreatitis (AP) compared to canine pancreatic lipase immunoreactivity (cPLI), which is considered the most sensitive and specific serum test available for dogs. Elevations in lipase activity have been observed in dogs with naturally occurring hypercortisolism (HC) and in those treated with exogenous steroids, which complicates the diagnosis of AP in dogs with HC. We compared lipase activity measured by DGGR and 1,2-diglyceride (1,2-DiG) assays in 22 dogs with HC, 22 with AP, and 22 healthy dogs. The dogs with HC had no clinical signs or ultrasonographic findings consistent with AP. DGGR lipase activity was elevated in 64% and 73% of the dogs with HC and AP, respectively, and in 18% of healthy dogs. 1,2-DiG lipase activity was high in 23% and 36% of the dogs with HC and AP, respectively, and in 5% of the healthy dogs. Both DGGR and 1,2-DiG lipase activities were significantly different between the healthy dogs and the other 2 groups, whereas no differences were detected between the dogs with HC and those with AP. Our results support a lack of specificity for both DGGR and 1,2-DiG lipase activity assays in aiding the diagnosis of AP in dogs with HC.  相似文献   

The Pliocene paradox (mechanisms for a permanent El Niño)     

Fedorov AV  Dekens PS  McCarthy M  Ravelo AC  deMenocal PB  Barreiro M  Pacanowski RC  Philander SG 《Science (New York, N.Y.)》2006,312(5779):1485-1489

During the early Pliocene, 5 to 3 million years ago, globally averaged temperatures were substantially higher than they are today, even though the external factors that determine climate were essentially the same. In the tropics, El Ni?o was continual (or "permanent") rather than intermittent. The appearance of northern continental glaciers, and of cold surface waters in oceanic upwelling zones in low latitudes (both coastal and equatorial), signaled the termination of those warm climate conditions and the end of permanent El Ni?o. This led to the amplification of obliquity (but not precession) cycles in equatorial sea surface temperatures and in global ice volume, with the former leading the latter by several thousand years. A possible explanation is that the gradual shoaling of the oceanic thermocline reached a threshold around 3 million years ago, when the winds started bringing cold waters to the surface in low latitudes. This introduced feedbacks involving ocean-atmosphere interactions that, along with ice-albedo feedbacks, amplified obliquity cycles. A future melting of glaciers, changes in the hydrological cycle, and a deepening of the thermocline could restore the warm conditions of the early Pliocene.  相似文献   

Minimal Plant Responsiveness to Summer Water Pulses: Ecophysiological Constraints of Three Species of Semiarid Patagonia     

Rodolfo A. Golluscio  Valeria Sigal Escalada  Juliana Pérez 《Strength and Conditioning Journal》2009,62(2):171-178

In arid ecosystems, a few large summer rains frequently differentiate wet years from dry ones. However, use of this additional water by plants has limited experimental evidence. We applied a 16-mm summer water pulse (12% of mean annual precipitation) to two plant communities of the Patagonian steppe, and compared responses of three dominant species, which can be ordered by decreasing xerophytism and increasing rooting depth and summer activity: 1) colapiche, evergreen dwarf shrub (Nassauvia glomerulosa [Lag.] Don); 2) coirón amargo, evergreen grass (Stipa speciosa Trin. et Rupr.); and 3) neneo, drought deciduous shrub (Mulinum spinosum [Cav.] Pers.). Shallow-rooted species (S. speciosa and N. glomerulosa), which use water from dry soil layers, showed a greater leaf water potential response to watering than deep-rooted species (M. spinosum). Leaf water potential response was greater and quicker in xerophytic species than in mesophytic ones (N. glomerulosa > S. speciosa > M. spinosum). However, this response only translated into leaf conductance and transpiration responses for coirón amargo, probably because the species with winter phenological cycle (N. glomerulosa) is less able to utilize summer water inputs than species with a summer phenological cycle (S. speciosa). The lack of response of deep-rooted M. spinosum in leaf conductance, transpiration, and photosynthesis may have been due to the high leaf water potential of control plants. Instead, in S. speciosa and N. glomerulosa net photosynthesis decreased below zero following watering, suggesting the start of growth pulses. The complex chain of plant processes triggered by rainfall, and the constraints imposed to different species by rooting depth, phenology, and xerophytism, could explain the frequent low response to both large rainfall events and above-average rainfall years in this arid community. Our results suggest that, paradoxically, water may be suboptimally used at local scales in arid rangeland ecosystems.  相似文献   

Dynamics of carbon and nitrogen in an extreme alkaline saline soil: A review     

Luc Dendooven  Rocio J. Alcántara-Hernández  Cesar Valenzuela-Encinas  Marco Luna-Guido  F. Perez-Guevara  Rodolfo Marsch 《Soil biology & biochemistry》2010,42(6):865-877

The soil of the former lake Texcoco is an ‘extreme’ alkaline saline soil with pH > 10 and electrolytic conductivity (EC) > 150 dS m⁻¹. These conditions have created a unique environment. Application of wastewater sludge to Texcoco soil showed that large amounts of NH₄⁺ were immobilized, NO₃⁻ was reduced aerobically, NO₂⁻ was formed and the mineralization of the organic material in the sludge was inhibited. A series of experiments were initiated to study the processes that inhibited the decomposition of organic material and affected the dynamics of mineral N. The large EC and pH inhibited the decomposition of easily decomposable organic material such as glucose and maize, although cellulolytic activity was observed in soil with pH 9.8 and EC 32.7 dS m⁻¹. The high soil pH favoured NH₃ volatilization of approximately 50 mg N kg⁻¹ soil within a day and a similar amount could be fixed on the soil matrix due to the dispersed minerals and their volcanic origin. Soil microorganisms immobilized large amounts of NH₄⁺ within a day when glucose was added to soil in excess of what was required for metabolic activity. Removal of NO₃⁻ from soil amended with glucose was not inhibited by 100% O₂ and NH₄⁺ indicating that the contribution of denitrification and assimilatory reduction to the reduction of NO₃⁻ was minimal while the formation of NO₂⁻ was not inhibited by 0.1% acetylene, known to inhibit nitrification. Additionally, the reduction of NO₃⁻ in the glucose-amended alkaline saline Texcoco soil was followed by an increase in the amount of NH₄⁺, which could not be due to denitrification. It was concluded that the reduction of NO₃⁻ and the formation of NO₂⁻ and NH₄⁺ in the glucose-amended soil was a result of aerobic NO₃⁻ reduction. A phylogenetic analysis of the archaeal community in the soil of the former lake Texcoco showed that some of the clones identified were capable of reducing NO₃⁻ aerobically to NO₂⁻ when glucose was added. A study of the diversity of the bacterial dissimilatory and respiratory nitrate-reducing communities indicated that bacteria could have contributed to the process.  相似文献