980 resultados para estimated average requirement
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Purpose: The objective of this study was to compare the estimated cost of clinical and surgical treatment for basl cell carcinoma of the eyelid. Methods: This was a pilot study of 12 patients with basal cell carcinoma receiving treatment with 5% imiquimod cream at the ocular plastic surgery center, medical school University of Sao Paulo (HC-FMUSP, Brazil). The cost of clinical treatment was estimated based on the time of treatment and amount of medication consumed by patients in the home setting. The cost of surgical treatment was estimated by ophthalmologists with experience in reconstructive plastic surgery based on analysis of images of the same patients. Surgeons responded to a questionnaire with four questions about surgical technique, surgical materials required, estimated duration of surgery and type of anesthesia. Results: Immunotherapy lasted from 8 to 12 weeks. All patients reported each cold-stored sachet with 5% imiquimod cream lasted 3 days. According to the institution, a box with 12 sachets costs BRL 480.00. Patients required 1.58-3.11 boxes for complete treatment, corresponding to a total cost of BRL 758.40-1,492.80. Based on image analysis, surgeons evaluated surgery would require 1-3 hours. The estimated cost of surgery room and staff was BRL 263.00, to which the cost of supplies was added. Thus, the total cost of surgical treatment was BRL 272.61-864.82. On the average, immunotherapy was 57,64% more costly than surgical treatment. Conclusions: Malignant eyelid tumors are a common finding in clinical ophthalmology. Surgery is still the treatment of choice at our institution, but immunotherapy with 5% imiquimod cream may be indicated for patients with multiple lesions or high surgical risk and for patients declining surgery for reasons of fear or esthetic concerns. The ability to estimate costs related to the treatment of malignant eyelid tumors is an important aid in the financial planning of health care institutions. Further studies should evaluate the possibility of institutions equating the cost of immunotherapy and surgical treatment by acquiring similar but less expensive medications.
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The quantification of ammonia (NH3) losses from sugarcane straw fertilized with urea can be performed with collectors that recover the NH3 in acid-treated absorbers. Thus, the use of an open NH3 collector with a polytetrafluoroethylene (PTFE)-wrapped absorber is an interesting option since its cost is low, handling easy and microclimatic conditions irrelevant. The aim of this study was to evaluate the efficiency of an open collector for quantifying NH3-N volatilized from urea applied over the sugarcane straw. The experiment was carried out in a sugarcane field located near Piracicaba, Sao Paulo, Brazil. The NH3-N losses were estimated using a semi-open static collector calibrated with N-15 (reference method) and an open collector with an absorber wrapped in PTFE film. Urea was applied to the soil surface in treatments corresponding to rates of 50, 100, 150 and 200 kg ha(-1) N. Applying urea-N fertilizer on sugarcane straw resulted in losses NH3-N up to 24 % of the applied rate. The amount of volatile NH3-N measured in the open and the semi-open static collector did not differ. The effectiveness of the collection system varied non-linearly, with an average value of 58.4 % for the range of 100 to 200 kg ha(-1) of urea-N. The open collector showed significant potential for use; however, further research is needed to verify the suitability of the proposed method.
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The quantification of ammonia (NH3) losses from sugarcane straw fertilized with urea can be performed with collectors that recover the NH3 in acid-treated absorbers. Thus, the use of an open NH3 collector with a polytetrafluoroethylene (PTFE)-wrapped absorber is an interesting option since its cost is low, handling easy and microclimatic conditions irrelevant. The aim of this study was to evaluate the efficiency of an open collector for quantifying NH3-N volatilized from urea applied over the sugarcane straw. The experiment was carried out in a sugarcane field located near Piracicaba, São Paulo, Brazil. The NH3-N losses were estimated using a semi-open static collector calibrated with 15N (reference method) and an open collector with an absorber wrapped in PTFE film. Urea was applied to the soil surface in treatments corresponding to rates of 50, 100, 150 and 200 kg ha-1 N. Applying urea-N fertilizer on sugarcane straw resulted in losses NH3-N up to 24 % of the applied rate. The amount of volatile NH3-N measured in the open and the semi-open static collector did not differ. The effectiveness of the collection system varied non-linearly, with an average value of 58.4 % for the range of 100 to 200 kg ha-1 of urea-N. The open collector showed significant potential for use; however, further research is needed to verify the suitability of the proposed method.
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The construction of a reliable, practically useful prediction rule for future response is heavily dependent on the "adequacy" of the fitted regression model. In this article, we consider the absolute prediction error, the expected value of the absolute difference between the future and predicted responses, as the model evaluation criterion. This prediction error is easier to interpret than the average squared error and is equivalent to the mis-classification error for the binary outcome. We show that the distributions of the apparent error and its cross-validation counterparts are approximately normal even under a misspecified fitted model. When the prediction rule is "unsmooth", the variance of the above normal distribution can be estimated well via a perturbation-resampling method. We also show how to approximate the distribution of the difference of the estimated prediction errors from two competing models. With two real examples, we demonstrate that the resulting interval estimates for prediction errors provide much more information about model adequacy than the point estimates alone.
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An additional ore field in the central part of the MARhas been discovered. Together with previously discovered Logachev (14°45'N) and Ashadze (12°58'N) ore fields, the new ore field constitutes a cluster with preliminarily estimated total ore reserve of >10 Mt, which is comparable with large continental massive sulfide deposits.
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Stubacher Sonnblickkees (SSK) is located in the Hohe Tauern Range (Eastern Alps) in the south of Salzburg Province (Austria) in the region of Oberpinzgau in the upper Stubach Valley. The glacier is situated at the main Alpine crest and faces east, starting at elevations close to 3050 m and in the 1980s terminated at 2500 m a.s.l. It had an area of 1.7 km² at that time, compared with 1 km² in 2013. The glacier type can be classified as a slope glacier, i.e. the relief is covered by a relatively thin ice sheet and there is no regular glacier tongue. The rough subglacial topography makes for a complex shape in the surface topography, with various concave and convex patterns. The main reason for selecting this glacier for mass balance observations (as early as 1963) was to verify on a complex glacier how the mass balance methods and the conclusions - derived during the more or less pioneer phase of glaciological investigations in the 1950s and 1960s - could be applied to the SSK glacier. The decision was influenced by the fact that close to the SSK there was the Rudolfshütte, a hostel of the Austrian Alpine Club (OeAV), newly constructed in the 1950s to replace the old hut dating from 1874. The new Alpenhotel Rudolfshütte, which was run by the Slupetzky family from 1958 to 1970, was the base station for the long-term observation; the cable car to Rudolfshütte, operated by the Austrian Federal Railways (ÖBB), was a logistic advantage. Another factor for choosing SSK as a glaciological research site was the availability of discharge records of the catchment area from the Austrian Federal Railways who had turned the nearby lake Weißsee ('White Lake') - a former natural lake - into a reservoir for their hydroelectric power plants. In terms of regional climatic differences between the Central Alps in Tyrol and those of the Hohe Tauern, the latter experienced significantly higher precipitation , so one could expect new insights in the different response of the two glaciers SSK and Hintereisferner (Ötztal Alps) - where a mass balance series went back to 1952. In 1966 another mass balance series with an additional focus on runoff recordings was initiated at Vernagtfener, near Hintereisferner, by the Commission of the Bavarian Academy of Sciences in Munich. The usual and necessary link to climate and climate change was given by a newly founded weather station (by Heinz and Werner Slupetzky) at the Rudolfshütte in 1961, which ran until 1967. Along with an extension and enlargement to the so-called Alpine Center Rudolfshütte of the OeAV, a climate observatory (suggested by Heinz Slupetzky) has been operating without interruption since 1980 under the responsibility of ZAMG and the Hydrological Service of Salzburg, providing long-term met observations. The weather station is supported by the Berghotel Rudolfshütte (in 2004 the OeAV sold the hotel to a private owner) with accommodation and facilities. Direct yearly mass balance measurements were started in 1963, first for 3 years as part of a thesis project. In 1965 the project was incorporated into the Austrian glacier measurement sites within the International Hydrological Decade (IHD) 1965 - 1974 and was afterwards extended via the International Hydrological Program (IHP) 1975 - 1981. During both periods the main financial support came from the Hydrological Survey of Austria. After 1981 funds were provided by the Hydrological Service of the Federal Government of Salzburg. The research was conducted from 1965 onwards by Heinz Slupetzky from the (former) Department of Geography of the University of Salzburg. These activities received better recognition when the High Alpine Research Station of the University of Salzburg was founded in 1982 and brought in additional funding from the University. With recent changes concerning Rudolfshütte, however, it became unfeasible to keep the research station going. Fortunately, at least the weather station at Rudolfshütte is still operating. In the pioneer years of the mass balance recordings at SSK, the main goal was to understand the influence of the complicated topography on the ablation and accumulation processes. With frequent strong southerly winds (foehn) on the one hand, and precipitation coming in with storms from the north to northwest, the snow drift is an important factor on the undulating glacier surface. This results in less snow cover in convex zones and in more or a maximum accumulation in concave or flat areas. As a consequence of the accentuated topography, certain characteristic ablation and accumulation patterns can be observed during the summer season every year, which have been regularly observed for many decades . The process of snow depletion (Ausaperung) runs through a series of stages (described by the AAR) every year. The sequence of stages until the end of the ablation season depends on the weather conditions in a balance year. One needs a strong negative mass balance year at the beginning of glacier measurements to find out the regularities; 1965, the second year of observation resulted in a very positive mass balance with very little ablation but heavy accumulation. To date it is the year with the absolute maximum positive balance in the entire mass balance series since 1959, probably since 1950. The highly complex ablation patterns required a high number of ablation stakes at the beginning of the research and it took several years to develop a clearer idea of the necessary density of measurement points to ensure high accuracy. A great number of snow pits and probing profiles (and additional measurements at crevasses) were necessary to map the accumulation area/patterns. Mapping the snow depletion, especially at the end of the ablation season, which coincides with the equilibrium line, is one of the main basic data for drawing contour lines of mass balance and to calculate the total mass balance (on a regular-shaped valley glacier there might be an equilibrium line following a contour line of elevation separating the accumulation area and the ablation area, but not at SSK). - An example: in 1969/70, 54 ablation stakes and 22 snow pits were used on the 1.77 km² glacier surface. In the course of the study the consistency of the accumulation and ablation patterns could be used to reduce the number of measurement points. - At the SSK the stratigraphic system, i.e. the natural balance year, is used instead the usual hydrological year. From 1964 to 1981, the yearly mass balance was calculated by direct measurements. Based on these records of 17 years, a regression analysis between the specific net mass balance and the ratio of ablation area to total area (AAR) has been used since then. The basic requirement was mapping the maximum snow depletion at the end of each balance year. There was the advantage of Heinz Slupetzky's detailed local and long-term experience, which ensured homogeneity of the series on individual influences of the mass balance calculations. Verifications took place as often as possible by means of independent geodetic methods, i.e. monoplotting , aerial and terrestrial photogrammetry, more recently also the application of PHOTOMODELLER and laser scans. The semi-direct mass balance determinations used at SSK were tentatively compared with data from periods of mass/volume change, resulting in promising first results on the reliability of the method. In recent years re-analyses of the mass balance series have been conducted by the World Glacier Monitoring Service and will be done at SSK too. - The methods developed at SSK also add to another objective, much discussed in the 1960s within the community, namely to achieve time- and labour-saving methods to ensure continuation of long-term mass balance series. The regression relations were used to extrapolate the mass balance series back to 1959, the maximum depletion could be reconstructed by means of photographs for those years. R. Günther (1982) calculated the mass balance series of SSK back to 1950 by analysing the correlation between meteorological data and the mass balance; he found a high statistical relation between measured and determined mass balance figures for SSK. In spite of the complex glacier topography, interesting empirical experiences were gained from the mass balance data sets, giving a better understanding of the characteristics of the glacier type, mass balance and mass exchange. It turned out that there are distinct relations between the specific net balance, net accumulation (defined as Bc/S) and net ablation (Ba/S) to the AAR, resulting in characteristic so-called 'turnover curves'. The diagram of SSK represents the type of a glacier without a glacier tongue. Between 1964 and 1966, a basic method was developed, starting from the idea that instead of measuring years to cover the range between extreme positive and extreme negative yearly balances one could record the AAR/snow depletion/Ausaperung during one or two summers. The new method was applied on Cathedral Massif Glacier, a cirque glacier with the same area as the Stubacher Sonnblickkees, in British Columbia, Canada. during the summers of 1977 and 1978. It returned exactly the expected relations, e.g. mass turnover curves, as found on SSK. The SSK was mapped several times on a scale of 1:5000 to 1:10000. Length variations have been measured since 1960 within the OeAV glacier length measurement programme. Between 1965 and 1981, there was a mass gain of 10 million cubic metres. With a time lag of 10 years, this resulted in an advance until the mid-1980s. Since 1982 there has been a distinct mass loss of 35 million cubic metres by 2013. In recent years, the glacier has disintegrated faster, forced by the formation of a periglacial lake at the glacier terminus and also by the outcrops of rocks (typical for the slope glacier type), which have accelerated the meltdown. The formation of this lake is well documented. The glacier has retreated by some 600 m since 1981. - Since August 2002, a runoff gauge installed by the Hydrographical Service of Salzburg has recorded the discharge of the main part of SSK at the outlet of the new Unterer Eisboden See. The annual reports - submitted from 1982 on as a contractual obligation to the Hydrological Service of Salzburg - document the ongoing processes on the one hand, and emphasize the mass balance of SSK and outline the climatological reasons, mainly based on the met-data of the observatory Rudolfshütte, on the other. There is an additional focus on estimating the annual water balance in the catchment area of the lake. There are certain preconditions for the water balance equation in the area. Runoff is recorded by the ÖBB power stations, the mass balance of the now approx. 20% glaciated area (mainly the Sonnblickkees) is measured andthe change of the snow and firn patches/the water content is estimated as well as possible. (Nowadays laserscanning and ground radar are available to measure the snow pack). There is a net of three precipitation gauges plus the recordings at Rudolfshütte. The evaporation is of minor importance. The long-term annual mean runoff depth in the catchment area is around 3.000 mm/year. The precipitation gauges have measured deficits between 10% and 35%, on average probably 25% to 30%. That means that the real precipitation in the catchment area Weißsee (at elevations between 2,250 and 3,000 m) is in an order of 3,200 to 3,400 mm a year. The mass balance record of SSK was the first one established in the Hohe Tauern region (and now since the Hohe Tauern National Park was founded in 1983 in Salzburg) and is one of the longest measurement series worldwide. Great efforts are under way to continue the series, to safeguard against interruption and to guarantee a long-term monitoring of the mass balance and volume change of SSK (until the glacier is completely gone, which seems to be realistic in the near future as a result of the ongoing global warming). Heinz Slupetzky, March 2014
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To date, understanding of ice sheet retreat within Pine Island Bay (PIB) following the Last Glacial Maximum (LGM) was based on seven radiocarbon dates and only fragmentary seafloor geomorphic evidence. During the austral summer 2009-2010, restricted sea ice cover allowed for the collection of 27 sediment cores from the outer PIB trough region. Combining these cores with data from prior cruises, over 133 cores have been used to conduct a detailed sedimentological facies analysis. These results, augmented by 23 new radiocarbon dates, are used to reconstruct the post-LGM deglacial history of PIB. Our results record a clear retreat stratigraphy in PIB composed of, from top to base; terrigenous sandy silt (distal glacimarine), pebbly sandy mud (ice-proximal glacimarine), and till. Initial retreat from the outer-continental shelf began shortly after the LGM and before 16.4 k cal yr BP, as a likely response to rising sea level. Bedforms in outer PIB document episodic retreat in the form of back-stepping grounding zone wedges and are associated with proximal glacimarine sediments. A sub-ice shelf facies is observed in central PIB and spans ~12.3-10.6 k cal yr BP. It is possible that widespread impingement of warm water onto the continental shelf caused an abrupt and widespread change from sub-ice shelf sedimentation to distal glacimarine sedimentation dominated by widespread dispersal of terrigenous silt between 7.8 and 7.0 k cal yr BP. The final phase of retreat ended before ~1.3 k cal yr BP, when the grounding line migrated to a location near the current ice margin.
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This paper proposes a method for assessing the groundwater renewable reserves of large regions for an average year, based on the integration of the recession curves for their basins springs or the natural base flow of their rivers. In this method, the hydrodynamic volume (or renewable reserves), were estimated from the baseflow equation. It was assumed that the flow was the same as the natural recharge, and that the recession coefficients were derived by the hydrogeological parameters and geometrical characteristics of aquifers, and adjusted to fit the recession curves at gauging stations. The method was applied to all the aquifers of Spain, which have a total groundwater renewable reserve of 86,895 hm3 four times the mean annual recharge. However, the distribution of these reserves is very variable; 18.6% of the country aquifers contain 94.7% of the entire reserve.
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El agua de riego en España se ha reducido del 80 % al 70% tras la rehabilitación de los sistemas tradicionales de riego y el incremento de riegos a presión. La política española ha favorecido la creación de nuevos regadíos con fines sociales, para asentar a la población rural en zonas con disponibilidad de recursos hídricos. Este contexto es aplicable a la Comunidad de Regantes “Rio Adaja” (CCRR), que comenzó a funcionar en 2010 por lo que se la ha elegido para evaluar el uso y productividad del agua y manejo del riego en CCRR modernizadas de la cuenca del Duero. El estudio del manejo del riego se realizó con evaluaciones de campo, el primer año de funcionamiento, en una muestra de sistemas de riego (pivotes centrales, ramales de avance frontal, cobertura total) representativa de los sistemas predominantes en la CCRR. Además, se analizó la carta de riego propuesta por el fabricante de los pivotes centrales, considerando una distribución de caudal continua a lo largo del ramal, y se propuso una nueva carta con emisores de riego que mejoraban la uniformidad de aplicación del agua. El uso del agua en la CCRR se evaluó considerando tanto los indicadores de eficiencia del riego: suministro relativo de riego (anual relative irrigation supply, ARIS), suministro relativo del agua (anual relativewater supply, ARWS), suministro relativo de precipitación (rainfall relative supply, RRS) como los de productividad: productividad del agua (water productivity, WP) productividad del agua de riego (irrigation water productivity, IWP) y productividad de la evapotranspiración (evapotranspiration water productivity, ETWP). Primero, se determinaron: las necesidades hídricas de los cultivos para mantener un contenido de humedad óptimo en su zona radical, el coeficiente dual del cultivo, el agua disponible total (ADP) y agua fácilmente aprovechable (AFA). Después, se estimaron las necesidades hídricas de los cultivos considerando tres años tipo: húmedo, normal y seco correspondientes a la probabilidad de disponibilidad de la precipitación del 20, 50 y 80%, respectivamente. Así mismo, se realizó una encuesta a los regantes de la CCRR para conocer la dosis de riego y rendimiento anual de los cultivos principales durante sus tres años de funcionamiento: 2010-2011, 2011-2012 y 2012-2013.Finalmente, se simuló el efecto del riego y su manejo en la producción de los cultivos y en la productividad del agua. Además, el modelo de simulación AQUACROP (Geerts et al., 2010) se ha utilizado para estudiar la mejora del uso del agua de los cultivos de la CCRR. Dado que este modelo requiere de calibración específica para cada cultivo y cada zona y dado que, de todos los cultivos de la CCRR, sólo el girasol cumplía el requisito, este cultivo fue elegido para estudiar si la estrategia de riego deficitario mejoraría el uso del agua. Los resultados obtenidos indican que el 90% de los sistemas de riego evaluados distribuye el agua con una uniformidad adecuada (CUC≥75%). La simulación de la distribución del agua con las cartas de riego propuestas por el fabricante en pivotes centrales resultó en coeficientes CUC< 75% y sus valores mejoraban al eliminar el aspersor distal. La uniformidad del riego mejoraría si se trabajase con la carta de riego propuesta y que se compone por emisores de riego seleccionados en este estudio. En la mayoría de los cultivos, se aplicó riegos deficitarios (ARIS < 1 en los dos primeros años de funcionamiento de la CCRR y riegos excedentarios (ARIS > 1) el tercer año siendo significativas las diferencias observadas. El manejo del riego fue bueno (0,9 ≤ ARWS ≤1,2) en la mayoría de los cultivos. Así mismo, los indicadores de productividad del agua (WP e IWP (€.m-3)) varió entre cultivos y años estudiados y, destacan los valores observados en: cebolla, patata, zanahoria y cebada. En general, la productividad del agua en los riegos deficitarios fue mayor observándose además, que los índices de productividad mayores correspondieron al año con precipitación mayor aunque, las diferencias entre sus valores medios no fueron significativas en las tres campañas de riego estudiadas. Los resultados apuntan a que la metodología del balance hídrico y las herramientas presentadas en este trabajo (uniformidad de distribución de agua, indicadores de eficiencia del uso de agua y de su productividad) son adecuadas para estudiar el manejo del agua en CCRR. En concreto, la uniformidad en la aplicación del agua de la CCRR mejoraría seleccionando emisores de riego que proporcionen una mayor uniformidad de distribución del agua, lo que conllevaría a cambiar el diámetro de la boquilla de los emisores y/o eliminar el aspersor distal. Así mismo, puede ser de interés adoptar estrategias de riego deficitario para incrementar la productividad en el uso del agua, y las rentas de los regantes, para lo cual se propone utilizar un patrón de cultivos de referencia. Finalmente, el riego deficitario puede ser una estrategia para mejorar la eficiencia y productividad en el uso del agua de la CCRR siempre que lleve asociado un manejo del riego adecuado que resulta, relativamente, más fácil cuando se dispone de sistemas de riego con una uniformidad de aplicación alta. Sin embargo su aplicación no sería aconsejable en los cultivos de remolacha azucarera, regado con sistemas de riego con un coeficiente de uniformidad de Christiansen CUC < 75%, y maíz, regado con sistemas de riego con un coeficiente de uniformidad de Christiansen CUC < 65%. ABSTRACT The irrigation scheme modernization and the increase of sprinkler irrigation area have reduced the irrigation water use from 80 to 70%. The national irrigation policy favored the creation of new irrigation schemes with the purpose to settle the rural population in areas with availability in water resources. Within this context, the irrigation district “Río Adaja” (CCRR) started in 2010 so, it has been chosen as a case study to evaluate the water use and the irrigation management in a modernized CCRR. Several field evaluations were carried out during the first operation year, in a sample of irrigation systems (center pivot, moving lateral and solid set) selected among all the systems in the CCRR. Likewise, the manufacturer irrigation chart for the center pivot systems has been considered and the pressure and discharge distribution along the pivot have been estimated, assuming a continuous flow along the pipe. Then; the sprinkler nozzles were selected order to increase the uniformity on water application. The water use in the CCRR has been assessed by considering the water use efficiency indicators: annual relative irrigation supply (ARIS), annual relative water supply (ARWS), relative rainfall supply (RRS) and also the productivity indicators: water productivity (WP), irrigation water productivity (IWP) and evapotranspiration water productivity (ETWP). On the one hand, it has been determined the crop water requirement (to maintain the optimal soil water content in the rooting zone), the dual crop coefficient, the total available water and the readily available water. The crop water requirement was estimated by considering the typical wet, normal and dry years which correspond to the probability of effective precipitation exceedance of 20, 50 and 80%, respectively. On the other hand, the irrigation depth and crop yield by irrigation campaign have been considered for the main crops in the area. This information was obtained from a farmer’s survey in 2010-2011, 2011-2012 and 2012-2013. For sunflower, the irrigation effect and its management on the crop yield and water productivity have been simulated. Also a deficit irrigation strategy, which improves the water resources, has been determined by means of AQUACROP (FAO). The results showed that 90% of the evaluated irrigation systems have adequate irrigation water application uniformity (CUC ≥ 75%). The CUC values in center pivots, which were calculated using the manufacturer irrigation chart, are below < 75% . However, these values would increase with the change of emitter nozzle to the proposed nozzles selection. The results on water use showed a deficit irrigation management (ARIS < 1), in most of crops during the first two operation years, and an excess in irrigation for the third year (ARIS > 1) although non-significant difference was observed. In most cases, the management of irrigation is adequate (0,9≤ ARWS≤ 1,2) although there are differences among crops. Likewise, the productivity indicators (WP and IWP (€.m-3)) varied among crops and with irrigation events. The highest values corresponded to onion, potato, carrot and barley. The values for deficit irrigation were the highest and the productivity indicators increased the year with the highest effective precipitation. Nevertheless, the differences between the average values of these indicators by irrigation campaign were non-significant. This study highlights that the soil water balance methodology and other tools used in the methodology are adequate to study the use and productivity of water in the irrigation district. In fact, the water use in this CCRR can be improved if the irrigation systems were designed with higher water distribution uniformity what would require the change of sprinkler nozzles and/or eliminate the end gun. Likewise, it is advisable to set up deficit irrigation strategies to increase the water productivity taking into account certain limits on water application uniformities. In this respect, a reference cropping pattern has been proposed and the limits for water uniformity have been calculated for several crops.
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Two experiments were conducted to estimate the standardized ileal digestible (SID) Trp:Lys ratio requirement for growth performance of nursery pigs. Experimental diets were formulated to ensure that lysine was the second limiting AA throughout the experiments. In Exp. 1 (6 to 10 kg BW), 255 nursery pigs (PIC 327 × 1050, initially 6.3 ± 0.15 kg, mean ± SD) arranged in pens of 6 or 7 pigs were blocked by pen weight and assigned to experimental diets (7 pens/diet) consisting of SID Trp:Lys ratios of 14.7%, 16.5%, 18.4%, 20.3%, 22.1%, and 24.0% for 14 d with 1.30% SID Lys. In Exp. 2 (11 to 20 kg BW), 1,088 pigs (PIC 337 × 1050, initially 11.2 kg ± 1.35 BW, mean ± SD) arranged in pens of 24 to 27 pigs were blocked by average pig weight and assigned to experimental diets (6 pens/diet) consisting of SID Trp:Lys ratios of 14.5%, 16.5%, 18.0%, 19.5%, 21.0%, 22.5%, and 24.5% for 21 d with 30% dried distillers grains with solubles and 0.97% SID Lys. Each experiment was analyzed using general linear mixed models with heterogeneous residual variances. Competing heteroskedastic models included broken-line linear (BLL), broken-line quadratic (BLQ), and quadratic polynomial (QP). For each response, the best-fitting model was selected using Bayesian information criterion. In Exp. 1 (6 to 10 kg BW), increasing SID Trp:Lys ratio linearly increased (P < 0.05) ADG and G:F. For ADG, the best-fitting model was a QP in which the maximum ADG was estimated at 23.9% (95% confidence interval [CI]: [<14.7%, >24.0%]) SID Trp:Lys ratio. For G:F, the best-fitting model was a BLL in which the maximum G:F was estimated at 20.4% (95% CI: [14.3%, 26.5%]) SID Trp:Lys. In Exp. 2 (11 to 20 kg BW), increasing SID Trp:Lys ratio increased (P < 0.05) ADG and G:F in a quadratic manner. For ADG, the best-fitting model was a QP in which the maximum ADG was estimated at 21.2% (95% CI: [20.5%, 21.9%]) SID Trp:Lys. For G:F, BLL and BLQ models had comparable fit and estimated SID Trp:Lys requirements at 16.6% (95% CI: [16.0%, 17.3%]) and 17.1% (95% CI: [16.6%, 17.7%]), respectively. In conclusion, the estimated SID Trp:Lys requirement in Exp. 1 ranged from 20.4% for maximum G:F to 23.9% for maximum ADG, whereas in Exp. 2 it ranged from 16.6% for maximum G:F to 21.2% for maximum ADG. These results suggest that standard NRC (2012) recommendations may underestimate the SID Trp:Lys requirement for nursery pigs from 11 to 20 kg BW.
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Spo11 and the Rad50-Mre11 complex have been indirectly implicated in processes associated with DNA replication. These proteins also have been shown to have early meiotic roles essential for the formation of a programmed DNA double-strand break known in Saccharomyces cerevisiae to initiate meiotic recombination. In both S. cerevisiae and the basidiomycete Coprinus cinereus, spo11 and rad50 mutants are defective in chromosome synapsis during meiosis. Here we demonstrate that a partial restoration of synapsis occurs in C. cinereus spo11 and rad50 mutants if premeiotic DNA replication is prevented. Double mutants were constructed with spo11–1 or rad50–4 and another mutant, spo22–1, which does not undergo premeiotic DNA replication. In both cases, we observed an increase in the percentage of nuclei containing synaptonemal complex (SC) structures, with concomitant decreases in the percentage of nuclei containing axial elements (AE) only or no structures. Both types of double mutants demonstrated significant increases in the average numbers of AE and SC, although SC-containing nuclei did not on average contain more AE than did nuclei showing no synapsis. Our results show that Spo11-induced recombination is not absolutely required for synapsis in C. cinereus, and that the early meiotic role of both Spo11 and Rad50 in SC formation partially depends on premeiotic S phase. This dependency likely reflects either a requirement for these proteins imposed by the premeiotic replication process itself or a requirement for these proteins in synapsis when a sister chromatid (the outcome of DNA replication) is present.