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Strontium and Neodymium isotopic analysis of the lithogenic fractions of the hole U1445A (International Ocean Discovery Program‐353) collected from the deep‐water end of the Mahanadi basin (western Bay of Bengal) was carried out to evaluate the sediment sources as well as to understand the link between the temporal variations in the Sr‐Nd isotope ratios and climatic and tectonic forcings during the last 6 Ma. The Sr‐Nd isotopic compositions along with Fe/Al ratios and clay mineralogy show tell‐tale signature of Ganga‐Brahmaputra sedimentation (Bengal fan) in the study area. The significant temporal fluctuations observed in the Sr‐Nd isotopic compositions suggest variation in the relative sediment contribution by the Ganga and Brahmaputra river systems, which in turn are controlled by monsoon intensity variations coupled with orographic effect, glaciation, and multiple tectonic activities. The results show the marked influence of glacial‐interglacials on the relative sediment contribution by Ganga and Brahmaputra rivers during 0–1.8 Ma, while the sedimentation during the 1.8–6 Ma time window was likely influenced by both climatic and tectonic forcings such as uplift of the Shillong plateau, eastern syntaxis development of Indo‐Burma wedge, reorganization of Brahmaputra river system. The present study is the first high resolution (122 samples within 6 Ma) Sr‐Nd isotope ratio analysis from the Bengal Fan. The study has brought to light multiple isotope fluctuations linked to climatic and tectonic forcings. The work also establishes dominant control of Ganga‐Brahmaputra sedimentation along the deep waters of the Indian east coast. Key Points: Sediments deposited in the deep waters of eastern Indian margins are predominantly derived from the HimalayasTemporal variations observed in Sr‐Nd isotope ratios indicate variation in relative sediment contribution by Ganga and Brahmaputra riversMonsoonal Intensity variation and tectonic processes control the sediment flux and sediment provenance in the Bengal fan sediments [ABSTRACT FROM AUTHOR]

Due to seasonal or interannual variability, the relevance of hydrological processes and of the associated model parameters can vary significantly throughout the simulation period. To achieve accurately identified model parameters, temporal variations in parameter dominance should be taken into account. This is not achieved if performance criteria are applied to the entire model output time series. Even when using complementary performance criteria, it is often only possible to identify some of the model parameters precisely. We present an innovative approach to improve parameter identifiability that exploits the information available regarding temporal variations in parameter dominance. Using daily parameter sensitivity time series, we construct a set of sensitivity-weighted performance criteria, one for each parameter, whereby periods of higher dominance of a model parameter and its corresponding process are assigned higher weights in the calculation of the associated performance criterion. These criteria are used to impose constraints on parameter values. We demonstrate this approach by constraining 12 model parameters for three catchments and examine ensemble hydrological simulations generated using these constrained parameter sets. The sensitivity-weighted approach improves in particular the identifiability for parameters whose corresponding processes are dominant only for short periods of time or have strong seasonal patterns. This results overall in slight improvement of model performance for a set of 10 contrasting performance criteria. We conclude that the sensitivity-weighted approach improves the extraction of hydrologically relevant information from data, thereby resulting in improved parameter identifiability and better representation of model parameters. [ABSTRACT FROM AUTHOR]

Uncertainties in hydro‐climatic projections are (in part) related to various components of the production chain. An ensemble of numerous projections is usually considered to characterize the overall uncertainty; however in practice a small set of scenario combinations are constructed to provide users with a subset that is manageable for decision‐making. Since projections are unavoidably uncertain, and multiple projections are typically informationally redundant to a considerable extent, it would be helpful to identify an informationally representative subset in a large model ensemble. Here a framework rooted in the information theoretic Maximum Information Minimum Redundancy concept is proposed for identifying a representative subset from an available ensemble of hydro‐climatic projections. We analyze an ensemble of 16 precipitation and temperature projections for Sweden, and use these as inputs to the HBV hydrological model to project river discharge until the mid of this century. Representative subsets are judged in terms of different statistical properties of three essential climate variables (precipitation, temperature and discharge), whilst we further assess the sensitivity of the optimized subset for different seasons and future periods. Our results indicate that a quarter to a third of the available set of projections can represent more than 80% of the total information of hydro‐climatic changes. We find that the representative subsets are sensitive to the regional hydro‐climatic characteristics and the choice of variables, seasons and periods of interest. Therefore we recommend that any selection process should not be solely driven by climatic variables but, rather, should also consider variables of the impact model. Plain Language Summary: The need for better understanding of climate change and its impact has led to an increasing number of climate models and consequently hydro‐climatic projections. Using a large set of projections, we present the information content and the redundant information when an ensemble is considered, and hence demonstrate how representative projections can be identified in order to overcome artifacts/biases introduced by a common hand‐picking approach. An identified subset reduced by almost 70% from the large ensemble is capable of representing more than 80% of the total information for precipitation, temperature and discharge; however the selected projections are sensitive to choice of variables, seasons, and period of interest. The size of the representative subset is also related to the regional hydro‐climatic characteristics. Key Points: Redundant information is present in large model ensembles; subsets should target towards maximizing independence and minimizing redundancyA subset of 20–35% of the total available projections can represent a large fraction of the ensemble range for hydro‐climatic changesThe identified subsets are sensitive to the choice of variables, seasons and future periods [ABSTRACT FROM AUTHOR]

Parameter estimation for hydrological models is complicated for many reasons, one of which is the arbitrary emphasis placed, by most traditional measures of fit, on various magnitudes of the model residuals. Recent research has called for the development of robust diagnostic measures that provide insights into which model structural components and/or data may be inadequate. In this regard, the flow duration curve (FDC) represents the historical variability of flow and is considered to be an informative signature of catchment behavior. Here we investigate the potential of using the recently developed conditioned entropy difference metric (CED) in combination with the Kling-Gupta efficiency (KGE). The CED respects the static information contained in the flow frequency distribution (and hence the FDC), but does not explicitly characterize temporal dynamics. The KGE reweights the importance of various hydrograph components (correlation, bias, variability) in a way that has been demonstrated to provide better model calibrations than the commonly used Nash-Sutcliffe efficiency, while being explicitly time sensitive. We employ both measures within a multiobjective calibration framework and achieve better performance over the full range of flows than obtained by single-criteria approaches, or by the common multiobjective approach that uses log-transformed and untransformed data to balance fitting of low and high flow periods. The investigation highlights the potential of CED to complement KGE (and vice versa) during model identification. It is possible that some of the complementarity is due to CED representing more information from moments >2 than KGE or other common metrics. We therefore suggest that an interesting way forward would be to extend KGE to include higher moments, i.e., use different moments as multiple criteria. [ABSTRACT FROM AUTHOR]

Rhodotorula is ubiquitous saprophytic yeast belonging to phylum Basidiomycota. These encapsulated basidiomycetes are being increasingly recognised as important emerging human pathogens. There are scanty reports of meningitis caused by Rhodurorula spp in HIV infected patients. We present one such case of meningitis by Rhodutorula glutinis in HIV-infected patient. The patient also had a past history of abdominal tuberculosis. The diagnosis of Rhodotorula was confirmed by Gram staining and culture of the cerebrospinal fluid ( CSF). Contamination was ruled out by repeated culturing of CSF from the same patient. Therapy with Amphotericin B showed good results. Patient was discharged from the hospital. However, in the seventh month of follow-up patient was readmitted with complaints of fever, breathlessness, altered sensorium, vomiting and succumbed to his illness. This time the CSF cultures remained negative for Rhodotorula, acid fast bacilli and other pyogenic organisms. Our last 11-year retrospective analysis of 8197 specimens received for mycological work-up showed that this is the first report of R. glutinis isolation from our institute. [ABSTRACT FROM AUTHOR]

Carbon retention is a critical issue in arable farming of the Indian Himalayas. This study, conducted from 2001 through 2010 on a sandy clay loam soil, evaluated the effect of tillage alterations (conventional tillage [CT] and zero tillage [ZT]) and selected irrigation treatments (I1: pre‐sowing, I2: pre‐sowing + active tillering or crown root initiation, I3: pre‐sowing + active tillering or crown root initiation + panicle initiation or flowering, and I4: pre‐sowing + active tillering or crown root initiation + panicle initiation or flowering + grain filling), applied at the critical growth stages to rice (Oryza sativa L.) and wheat (Triticum aestivum L.) on soil organic C (SOC) retention and its pools, soil aggregation, and aggregate‐associated C contents in the 0‐ to 30‐cm soil layer. Results indicate that the plots under ZT had nearly 17 and 14% higher total SOC and particulate organic C contents compared with CT (∼9.8 and 3.6 g kg−1 soil) in the 0‐ to 5‐cm soil layer after 9 yr of cropping, despite similar mean aboveground biomass yields of both crops on both CT and ZT plots. Tillage had no effect on C pools in the subsurface layers. Irrigation had positive impact on SOC content in the 0‐ to 5‐ and 5‐ to 15‐cm layers. Although the labile pools of SOC were positively affected by ZT, the recalcitrant pool was not. Plots under ZT and I4 also had higher large and small macroaggregates and macroaggregate‐associated SOC. Thus, adoption of ZT is the better management option for soil C improvement than CT, and irrigation generally enhances the positive impacts. [ABSTRACT FROM AUTHOR]

Observing system simulation experiments were used to investigate ensemble Bayesian state-updating data assimilation of observations of leaf area index (LAI) and soil moisture (&thgr;) for the purpose of improving single-season wheat yield estimates with the Decision Support System for Agrotechnology Transfer (DSSAT) CropSim-Ceres model. Assimilation was conducted in an energy-limited environment and a water-limited environment. Modeling uncertainty was prescribed to weather inputs, soil parameters and initial conditions, and cultivar parameters and through perturbations to model state transition equations. The ensemble Kaiman filter and the sequential importance resampling filter were tested for the ability to attenuate effects of these types of uncertainty on yield estimates. LAI and &thgr; observations were synthesized according to characteristics of existing remote sensing data, and effects of observation error were tested. Results indicate that the potential for assimilation to improve end-of-season yield estimates is low. Limitations are due to a lack of root zone soil moisture information, error in LAI observations, and a lack of correlation between leaf and grain growth. [ABSTRACT FROM AUTHOR]

This study compared the efficacy and tolerability of an optimized botanical combination containing policosanol, tomato extract, orally bioavailable grape procyanidins and Oenothera biennis oil against placebo in the management of patients with primary hypercholesterolemia and mixed dyslipidemia. Such a combination is endowed with biological properties targeted to cholesterol control and vasoprotection. This randomized, double-blind, parallel-group trial consisted of a 6 week treatment period following 4 week baseline period, and a 2 week post-treatment follow-up. At baseline, both the groups were comparable to each other. Both the active treatment and the placebo group included 30 patients (active treatment: mean age 46.80 ± 7.43 years, nine males; placebo: mean age 45.50 ± 6.76 years, eight males). Significant reductions in the LDL-cholesterol (LDL-C; −17.33% from baseline, p < 0.001) and total cholesterol (TC; −13.38% from baseline, p < 0.0001) values over the treatment period were observed with the tested product. The treatment also resulted in reductions in C-reactive protein (CRP), malondialdehyde (MDA) and superoxide dismutase (SOD) values, which are indices of oxidative stress. This rational combination of different compounds is effective and safe in lowering the elevated LDL-C and TC values. It is also effective in the modulation of the oxidation indices values; however, a further long term study in a larger population would be needed in order to confirm these preliminary findings. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article presents study which evaluates the conceptual rain-fall and time-invariant models parameters through temporal clustering. It states that the period of hydrological similarity was determined by temporal clustering of hydrological information. It mentions that the increase in the average of precipitation is a result of the increase in soil moisture. It adds that the periods of wetting, drying and runoff dynamics of the catchment are visible in the organization of clusters.

Environmental models have become increasingly complex with greater attention being given to the spatially distributed representation of processes. Distributed models have large numbers of parameters to be specified, which is typically done either by recourse to a priori methods based on observable physical watershed characteristics, by calibration to watershed input-state-output data, or by some combination of both. In the case of calibration, the high dimensionality of the parameter search space poses a significant identifiability problem. This article discusses how this problem can be addressed, utilizing additional information about the parameters through a process known as regularization. Regularization, in its broadest sense, is a mathematical technique that utilizes additional information or constraints about the parameters to reduce problems related to over-parameterization. This article develops and applies a regularization approach to the calibration of a version of the Hydrology Laboratory Distributed Hydrologic Model (HL-DHM) developed by the US National Weather Service. A priori parameter estimates derived using the approach by Koren et al. (2000) were used to develop regularization relationships to constrain the feasible parameter space and enable existing global optimization techniques to be applied to solve the calibration problem. In a case study for the Blue River basin, the number of unknowns to be estimated was reduced from 858 to 33, and this calibration strategy improved the model performance while preserving the physical realism of the model parameters. Our results also suggest that the commonly used parameter field 'multiplier' approach may often not be appropriate. [ABSTRACT FROM AUTHOR]

The article focuses on air pollution and the challenges involved in formulating an air quality management plan in Indore, India. It includes information on the city of Indore and Madhya Pradesh and discusses issues included in the creation of an effective plan in managing air pollution. It also presents the description of a 3D-logical model which will be used in the design and evaluation of air environmental policies. According to the author, India has good regulations on air pollution but its urban areas suffer from inadequate implementation of policies at all levels.

The article focuses on the environmental problem in the city of Indore in Madhya Pradesh, India and the initiative done by the authorities in solving the problem. Industrialization in the area which concentrates on the state's mineral resources was pointed as the caused of the terrible environmental problem in the vicinity. Industrial activities had triggered the loss of agricultural lands and open space, contamination of pollutants into the water and air and severe pile of the industrial solid waste. In order to lessen the existing problem, an environmental management plan have been formulated which studies the delicate areas in the country. Several factor hindered the balance between environment and development which made the planners to mix ecological considerations into industrial development.

Background: Anterior sciatic nerve blocks can be complicated by several problems. Pain can be caused by bony contacts and, in obese patients, identification of the landmarks is frequently difficult. Methods: In a first step, 100 normal anterior-posterior pelvic X-rays were analyzed. The landmarks of the classical anterior approach were drawn on these X-rays and assessed for their sufficiency. Then, in a prospective case study, 200 consecutive patients undergoing total knee replacement were investigated. These patients received femoral and sciatic nerve catheters for postoperative pain management. Using modified anatomical landmarks, sciatic nerve catheters were inserted 5 cm distal from the insertion site of the femoral nerve block perpendicularly in the midline of the lower extremity. This midline connected the insertion site of the femoral nerve catheter to the midpoint between the medial and lateral epicondyle. Correct catheter positioning was verified by magnetic resonance imaging (MRI) in six patients. Results: Evaluation of pelvic X-rays showed that puncture following the classical landmarks pointed in 51% at the lesser trochanter, in 5% medial to the lesser trochanter and in 42% directly at the femur. In the latter patients, location of the sciatic nerve would have been difficult or even impossible. Using our modified anterior approach, the sciatic nerve could be blocked in 196 patients (98%). In nine patients (4.5%) blockade of the posterior femoral cutaneous nerve failed. Vascular puncture happened in 10 (5%) and bony contact in 35 patients (17.5%). Median puncturing depth was 9.5 (7.5-14) cm. Correct sciatic nerve catheter positioning was verified in all patients who underwent MRI. Conclusion: Our landmarks for locating the sciatic nerve help to avoid bony contacts and thereby reduce pain during puncture. Our method reliably enabled catheter placement. [ABSTRACT FROM AUTHOR]

The effects of variation of the substrate's dielectric constant and of various geometries on photonic band gap (PBG) are studied on a microstrip-type periodic metallic structure, and the experimental findings are presented and discussed. In this study, air is chosen as the dielectric material of the substrate. A well-defined PBG has been observed in all the above cases. The band-gap changes in the microwave region with the variation of the substrate's dielectric constant and the geometry of the periodic metallic structure are due to characteristic impedance. The transmission loss has been found to decrease with an increase in the dielectric constant of the substrate. Thus, it is concluded that the dielectric constant combined with the characteristic impedance of the periodic structure plays an important role in the formation of PBG. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 41: 399–403, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20152 [ABSTRACT FROM AUTHOR]

Market-based approaches to environmental protection aim to improve environmental performance through market signals rather than through explicit mandates regarding pollutant-control methods. These policy approaches, which can include instruments such as tradable permits or pollution charges, are often described as "harnessing market forces." If they are well-designed and implemented, market-based approaches encourage firms and individuals to undertake pollution prevention and control efforts that are in their own interests, while also collectively meeting policy goals. This article describes an analytical model developed for managing industrial air emissions. The model calculates optimum suspended particulate matter abatement levels at a variety of selected emitting sources, with the objective of determining how abatement can be achieved at minimum cost.

Restenosis after revascularization procedures is accelerated in persons with type 2 diabetes. The current study tested the hypothesis that the neointimal response to endovascular injury is enhanced in female obese Zucker (OZ) rats, a model of type 2 diabetes. Animals were randomized to receive either a standard diet (SD) or a diabetogenic diet (DD) for 6 weeks. Four weeks later, balloon injury of the right common carotid artery was induced. All rats were euthanized 2 weeks after injury. Lean Zucker (LZ) rats served as controls. At the time of death, plasma glucose was elevated in OZ rats fed a SD (208 ± 13 mg/dl) and a DD (288 ± 21 mg/dl) compared to corresponding LZ rats (SD: 153 ± 8; DD: 132 ± 7 mg/dl). The ratio of high-density lipoprotein cholesterol (HDLc) to total cholesterol (Totc), an index of atherogenicity, was reduced in OZ rats on both diets (SD: 0.77 ± 0.06; DD: 0.80 ± 0.09) compared to LZ controls (SD: 1.11 ± 0.02; DD: 1.20 ± 0.05). Histomorphometric analysis of injured arteries showed that the intima to media (I : M) ratio was significantly increased in OZ (1.37 ± 0.07) compared to LZ (0.79 ± 0.08) rats. Elevations in plasma glucose and triglycerides (Tg) correlated positively and decreases in HDLc negatively with an increased I : M ratio. Administration of the DD did not further enhance the I : M ratio in LZ (0.87 ± 0.06) or OZ (1.29 ± 0.09) rats. These results suggest that neointima formation following endoluminal injury of the carotid artery is enhanced at an early stage in the development of diabetes mellitus. [ABSTRACT FROM AUTHOR]

Focuses on conceptual modelling that requires the identification of a suitable model structure and the estimation of parameter values through calibration against observed data. A lack of objective approaches to evaluate model structures and the inability of calibration procedures to distinguish between the suitability of different parameter sets are major sources of uncertainty in current modelling procedures. This paper presents an approach analysing the performance of the model in a dynamic fashion resulting in an improved use of available information. Model structures can be evaluated with respect to the failure of individual components, and periods of high information content for specific parameters can be identified. The procedure is termed dynamic identifiability analysis (DYNIA) and is applied to a model structure built from typical conceptual components.

We present our experimental findings on microstrip-type metallic photonic band gap (PBG) periodic structures prepared using a commercial aluminum foil. Effect of change in geometry of the periodic dielectric structure, namely, period, rectangular hole length, and defect on PBG, is studied. It is found that as the rectangular-hole-cut dimension decreases in terms of length, the lower edge of the band gap decreases toward the lower frequency side of the microwave region. It is also observed that as the defect length increases, the band gap edge again shifts toward the lower frequency side. These findings of band gap with air as substrate confirm the role of wave impedance in purely metallic periodic structures. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 35: 483–486, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10644 [ABSTRACT FROM AUTHOR]

Offers a brief history and mission of SAHRA, a National Science Foundation science and technology center on sustainability of semi-arid hydrology and riparian areas.

In a previous study a spatially distributed hydrological model, based on the MIKE SHE code, was constructed and validated for the 375 000 km² Senegal River basin in West Africa. The model was constructed using spatial data on topography, soil types and vegetation characteristics together with time-series of precipitation from 112 stations in the basin. The model was calibrated and validated based on river discharge data from nine stations in the basin for 11 years. Calibration and validation results suggested that the spatial resolution of the input data in parts of the area was not sufficient for a satisfactory evaluation of the modelling performance. The study further examined the spatial patterns in the model input and output, and it was found that particularly the spatial resolution of the precipitation input had a major impact on the model response. In an attempt to improve the model performance, this study examines a remotely sensed dryness index for its relationship to simulated soil moisture and evaporation for six days in the wet season 1990. The index is derived from observations of surface temperature and vegetation index as measured by the NOAA Advanced Very High Resolution Radiometer (AVHRR) sensor. The correlation results between the index and the simulation results are of mixed quality. A sensitivity analysis, conducted on both estimates, reveals significant uncertainties in both. The study suggests that the remotely sensed dryness index with its current use of NOAA AVHRR data does not offer information that leads to a better calibration or validation of the simulation model in a spatial sense. The method potentially may become more suitable with the use of the upcoming high-resolution temporal Meteosat Second Generation data.

The inability to develop an accurate and precise parameter estimation method for catchment hydrochemical models has been a persistent problem. We investigate the use of multicriteria calibration techniques and the selection of the criteria as a first step in solving this problem. We applied a multicriteria search algorithm to the Alpine Hydrochemical Model (AHM) of the Emerald Lake watershed, Sequoia National Park, California. A total of 21 chemical and hydrologic criteria were available for determining model performance. Four subsets of these criteria were selected for the multicriteria analysis using three different methods. The first set used the four least correlated observations of stream chemical composition. A second set of criteria was determined by using the four species with the least correlated root mean square error criteria values (ρ < 0.05 for each pair). Finally, two sets were chosen using the results of a multicriteria sensitivity analysis. The most accurate and precise results were observed using criteria selected using results from a sensitivity analysis, with the correlation analyses being a poor method for selecting criteria. This set of criteria emphasizes attributes of the model structure, the observations, and our understanding of the processes influencing watershed hydrology and water quality. Also, our results gave improved estimates of several hydrologic and biogeochemical processes in addition to identifying a flaw in the current representation of mineral weathering within the AHM, as applied to the Emerald Lake watershed. [ABSTRACT FROM AUTHOR]

Abstract Introgression of the winter gene pool into spring wheat is being considered as one of the strategies to break through the yield plateau. However, little information is available on the combining ability of these two important but distinct groups of wheats in Indian conditions. Therefore, the present study was undertaken to determine the combining ability and gene action of yield and yield attributes in winter x spring wheat crosses. Seventy F[sub 1] progenies developed by 14 winter and five spring wheat lines using a line x tester design were evaluated, along with their parents, for yield and yield attributes in a randomized complete block design under field conditions. The mean squares for all the characters studied showed highly significant differences. The mean squares due to female x male interactions were significant for all the characters studied except for grains per ear and grain weight per ear. Additive genetic effects were found to play a key role in controlling the expression of days to heading, plant height and spikelets per ear. 'MV 19' and 'Stepniak'/'Karvuna' among winter and 'PBW 65' among spring wheats were good general combiners for most of the yield attributes studied. The estimates for specific combining ability effects suggested that, although general combining ability (GCA) effects of most winter wheats are either average or poor, their combination can give desirable genotypes with spring wheat parents possessing a high GCA. [ABSTRACT FROM AUTHOR]

The uncertainty in a given hydrologic prediction is the compound effect of the parameter, data, and structural uncertainties associated with the underlying model. In general, therefore, the confidence in a hydrologic prediction can be improved by reducing the uncertainty associated with the parameter estimates. However, the classical approach to doing this via model calibration typically requires that considerable amounts of data be collected and assimilated before the model can be used. This limitation becomes immediately apparent when hydrologic predictions must be generated for a previously ungauged watershed that has only recently been instrumented. This paper presents the framework for a Bayesian recursive estimation approach to hydrologic prediction that can be used for simultaneous parameter estimation and prediction in an operational setting. The prediction is described in terms of the probabilities associated with different output values. The uncertainty associated with the parameter estimates is updated (reduced) recursively, resulting in smaller prediction uncertainties as measurement data are successively assimilated. The effectiveness and efficiency of the method are illustrated in the context of two models: a simple unit hydrograph model and the more complex Sacramento soil moisture accounting model, using data from the Leaf River basin in Mississippi. [ABSTRACT FROM AUTHOR]

Four cold-tolerant rice varieties, viz. 'Khonorullo', 'Namyi', 'Abor B' and 'Meghalaya-1' were crossed with two cold-susceptible ones, viz. 'Pusa 33' and 'Subhadra' (DR92), in all possible combinations to study the inheritance of gene(s) governing panicle exsertion and their allelic relationship among cold-tolerant varieties. F1 hybrids of all the crosses showed complete panicle exsertion indicating dominance of this trait. Segregation pattern of panicle exsertion in F2 and backcrosses show that all the four cold-tolerant varieties possessed a single dominant gene designated as Ctr-1. Absence of segregation for panicle exsertion in an F2 generation obtained from intercrosses of cold-tolerant varieties suggests that the dominant genes in all the four cultivars are allelic. [ABSTRACT FROM AUTHOR]

Immunization of male rats and monkeys with gonadotropin-releasing hormone (GnRH) conjugated to a carrier results in a dramatic atrophy of the prostate. GnRH, linked to either diphtheria toxoid or tetanus toxoid as carrier, is now being evaluated for its use in the immunotherapy of hormone- dependent prostatic enlargement in men. This report deals with the phenomenon of carrier-induced, epitope-specific regulation in the GnRH-carrier system. In experiments designed to assess the influence of the carrier on antibody responses to the ‘self’ hapten GnRH, we show that preimmunization with carriers diphtheria toxoid and tetanus toxoid results in a strain-dependent inhibition of anti-GnRH responses in mice. Results of adoptive transfer experiments indicate that T cells from carrier-presensitized mice are responsible for suppression of anti-haptenic antibodies and that T cells from conjugate-immunized mice, on the other hand, can actually help overcome hyporesponsiveness. [ABSTRACT FROM AUTHOR]