Residual Effects Of Treatments Research Articles

Controlled Clinical Trial of Zolpidem for the Treatment of Insomnia Associated With Attention-Deficit/ Hyperactivity Disorder in Children 6 to 17 Years of Age

The goal was to evaluate the hypnotic efficacy of zolpidem at 0.25 mg/kg per day (maximum of 10 mg/day), compared with placebo, in children 6 through 17 years of age who were experiencing insomnia associated with attention-deficit/hyperactivity disorder. An 8-week, North American, multicenter, double-blind, placebo-controlled, parallel-group study was conducted. Patients underwent stratification according to age (6-11 years [N = 111] or 12-17 years [N = 90]) and were assigned randomly to receive treatment with the study drug or placebo (in a 2:1 ratio). The primary efficacy variable was latency to persistent sleep between weeks 3 and 6. Secondary efficacy variables also were assessed, and behavioral and cognitive components of attention-deficit/hyperactivity disorder were monitored. Safety was assessed on the basis of reports of adverse events, abnormal laboratory data, vital signs, and physical examination findings. The potential for next-day residual effects also was assessed. The baseline-adjusted mean change in latency to persistent sleep at week 4 did not differ significantly between the zolpidem and placebo groups (-20.28 vs -21.27 minutes). However, differences favoring zolpidem were observed for the older age group in Clinical Global Impression scores at weeks 4 and 8. No next-day residual effects of treatment were associated with zolpidem, and no rebound phenomena occurred after treatment discontinuation. Central nervous system and psychiatric disorders were the most-frequent treatment-emergent adverse events (>5%) that were observed more frequently with zolpidem than with placebo; these included dizziness, headache, and hallucinations. Ten (7.4%) patients discontinued zolpidem treatment because of adverse events. Zolpidem at a dose of 0.25 mg/kg per day to a maximum of 10 mg failed to reduce the latency to persistent sleep on polysomnographic recordings after 4 weeks of treatment in children and adolescents 6 through 17 years of age who had attention-deficit/hyperactivity disorder-associated insomnia.

Eficácia do herbicida amicarbazone no controle em pós-emergência de espécies de corda-de-viola (Ipomoea grandifolia e Merremia cissoids)

Different weeds species are present in Brazilian sugar cane areas interfering negatively in productive process, and morningglory species, Ipomoea sp. and Merremia sp., are outstanding, particularly in raw cane areas. This way, the objective of this study was to verify the effectiveness of amicarbazone herbicide in controlling Ipomoea grandifolia and Merremia cissoides species, applied in post emergency and compared to 2,4-D herbicide. So, it was conducted an experiment, in green house conditions, in pots, with Latossoil Red distrofic (LRd), seeded with weeds. The experimental design used was entirely randomized with five treatments and four replications, and mediums submitted to Tukey test at 5% of probability. Treatments consisted of 700, 1050, 1400 g i.a. ha-1 of amicarbazone, 1612 g i.a. ha-1 of 2,4-D and an check. Treatments application was carried out in post-emergence, when weeds containing 15 cm tall, and at 7, 14 and 21 days after application (DAA) and the control was assessed, with dossel plants collect for obtaining dry mass, at 21 DAA. After collecting plants, it was conducted a new sowing in pots with the same weeds species and at 7, 14 and 21 days after sowing (DAS) visual control evaluations were conducted, in order to verify the residual effect of treatments. The experimental design was entirely randomized with five treatments and four replications, and mediums submitted to Tukey test at 5% of probability. It was verified that, independent of morningglory species studied, amicarbazone herbicide at 700, 1050, 1400 g i.a. ha-1 doses showed total control at 21 DAA, as well as up to 21 DAS, it was also observed excellent residual effect for this herbicide.

Organic manuring for soil biological health and productivity of a wheat - soybean cropping system in the Vertisols of central India

Soybean (Glycine max (L.) Merr.)–wheat (Triticum aestivum L.) is the dominant cropping system in the Vertisols of central India due to congenial climate, development of agro-industries, and export opportunities. Both are high-value crops, and raising them using organics may further improve produce quality and help in sustaining long-term productivity of the system. Information is lacking on how to sustain the system with the sole use of organics or biofertilisers in Vertisols. A long-term study was made during 1995–2002 at Indore, India, to evaluate the effectiveness of 3 organic manures [farmyard manure (FYM), poultry manure (PM) and vermicompost (VC) at varying rates] and biofertilisers (Azotobacter + phosphate solubilising bacteria) on productivity, grain quality, soil fertility, and profitability of a wheat–soybean cropping system. Grain yield of wheat was significantly increased with PM at 2.5–10 t/ha or FYM at 10–20 t/ha compared with the control. However, the highest productivity was obtained with PM at 10 t/ha, which even performed better than NPK, indicating that NPK fertilisers alone did not provide adequate and balanced nutrition for potential yield of the crop. Quality parameters of durum wheat, viz. protein content, hectolitre weight and sedimentation value, increased, while yellow berry content decreased significantly with PM at 2.5–10.0 t/ha compared with the control. Soybean yields were significantly influenced by the residual effect of organic manuring treatment applied to wheat. The treatment receiving PM at 10 t/ha produced the highest grain yield of wheat. However, this treatment could not produce a similar response in soybean yield due to production of excessive vegetative growth, adversely affecting grain yield. Superiority of PM over FYM, vermicompost and biofertilisers was evident in the overall profitability of the system. Various soil fertility parameters including chemical and biological properties showed conspicuous improvement over the initial status under the FYM and PM treatments. Microbial biomass C and activities of phosphatase and dehydrogenase were increased significantly with applications of manures. Sustainability yield index was maximum under PM at 5–10 t/ha, followed by NPK. Results suggested that application of PM at 5–10 t/ha to wheat was essential for improving productivity, grain quality, profitability, soil health, and sustainability of a wheat–soybean system.

A Markov Model Simulation of the Impact of Treatment Persistence in Postmenopausal Osteoporosis

The Markov model followed a cohort of patients over 10 years to estimate the total number of incident osteoporotic fractures by age for the overall population of women with diagnosed postmenopausal osteoporosis in France (mean age, 71.1 years +/-9.6; range, 50-96 years). The impact of clinical efficacy, persistence, and residual treatment effects data on predicted fracture risk was also estimated in the model. Predicted numbers of incident fractures appeared consistent with published data. Compared with no treatment, the relative risk of fracture over 10 years was 0.831 for weekly bisphosphonate treatment with an assumed persistence rate of 51% after 1 year (absolute risk reduction = 11.4%). This relative risk decreased to 0.731 (absolute risk reduction=18.1%) if hypothetical full-treatment persistence was achieved. In terms of public health, improving persistence with bisphosphonate treatment by only 20% could have the same impact as a 20.2% increase in clinical efficacy. The benefit associated with improved persistence declines as full persistence is approached. Improving persistence can increase treatment effectiveness. Giving greater priority to persistence interventions might have a greater impact on the health of osteoporotic women than advances in treatment efficacy.

Effect of treating lettuce surfaces with acidulants on the behaviour of Listeria monocytogenes during storage at 5 and 20 °C and subsequent exposure to simulated gastric fluid

The effect of acid decontamination on the growth/survival of Listeria monocytogenes on fresh lettuce ( Lactusa sativa) during storage and subsequent exposure to a simulated gastric fluid was studied. Fresh lettuce, inoculated with L. monocytogenes (3 log cfu/cm 2), was immersed (20 °C, 90 s) in water (W), lactic acid (LA), acetic acid (AA), propionic acid (PA) and citric acid (CA) at concentrations 0.5 and 1.0%, and then stored aerobically at 5 and 20 °C for 20 and 10 days, respectively. The immediate post-treatment reduction of L. monocytogenes was less than 1 log cfu/cm 2 for all treatments tested. The level of L. monocytogenes on W treated lettuce did not change during storage at 5 °C but increased significantly ( P < 0.05) and reached levels of 10 6–10 7 cfu/cm 2 at 20 °C. The residual effect of acid decontamination treatments during storage was found to be strongly dependent on the type and concentration of the acid solution. Decontamination with 0.5% AA, PA and CA did not have any antimicrobial effect and in some cases stimulated growth of the pathogen. The latter could be attributed to suppression of lettuce natural microflora. In contrast, decontamination with 0.5% LA resulted in a decrease of the pathogen during storage at 5 °C and in an extended lag phase at 20 °C. Increasing the concentration of acid solutions to 1% resulted in a rapid decline of L. monocytogenes for all acids tested except for CA, in which the behaviour of the pathogen was similar to that observed in W treated lettuce. The results from the sensory analysis showed that decontamination of lettuce with AA and PA led to a significant ( P < 0.05) negative effect on the overall appearance of lettuce while the sensory score of samples treated with LA and CA during storage was very close to that of W treated lettuce ( P > 0.05). The above results from the sensory analysis were confirmed by color analysis of lettuce. In order to evaluate the potential acid adaptation phenomena induced by acid decontamination interventions, the survival of L. monocytogenes during exposure to a simulated gastric fluid after prior storage of decontaminated lettuce was studied. The results showed that the tested decontamination treatments did not increase the acid tolerance of L. monocytogenes. In contrast, LA treatments sensitized the pathogen to the acidic simulated stomach conditions indicating a decreased virulence potential.

Comparisons between ITT and treatment emergent adverse event analyses

Different from the use of intention-to-treat (ITT) analysis for efficacy evaluation, many pharmaceutical companies currently use treatment emergent (TE) analysis for adverse event (AE) safety analysis. In the TE analysis, study period and AEs occurring after a pre-specified post-treatment window will not be included. One consideration for using the TE AE analysis is that including substantial off-drug period and events in the analysis may dilute the power for detecting safety signals especially if after discontinuation residual treatment effect diminishes quickly. We perform quantitative analyses to compare the unbiasedness and power of the ITT and TE AE analyses under several different settings and metrics (difference in rates and relative risk). Results show that unbiasedness and power are not always in the same direction. The choice of an approach for a particular trial should depend on the focus of the analysis. A data example is used to illustrate these points.

Greenhouse soil solarization: effect on weeds, nematodes and yield of tomato and melon

Phase-out of methyl bromide and health concerns related to the use of pesticides are increasing the interest in alternative control strategies. Soil solarization is an effective, safe and cheap technique for the control of soil-borne pathogens and weeds. However, knowledge of the long-term effects of solarization, as well as of repeated solarization cycles, is scarce. Such knowledge should in particular help to minimize the number of solarization treatments. Therefore, we tested the residual effect of a single solarization treatment and the effects of two or three solarization cycles on root-knot nematodes, weeds and crop yield for three years on greenhouse-grown tomato and melon. Soil solarization was applied for either one, two or three consecutive years on a soil infested by the root-knot nematode Meloidogyne javanica and many annual and perennial weed species. An untreated soil was used as a control. At the end of each crop cycle yield parameters were recorded, weeds were identified and counted, and nematode infestation was evaluated. Our results show that a single solarization treatment significantly increased yields by +116%, and strongly reduced nematode infestation of −99% of infested plants and of −98% of the root gall index in the following melon crop. It also suppressed annual weed emergence three years later. Plant yields from two- and three-year solarized soil were always higher than nonsolarized control: +284% and +263%, respectively, for tomato, and +162% and +368%, respectively, for melon. Further, two- and three-year solarization treatments almost completely suppressed the infestation of the M. javanica nematode in tomato, and reduced the nematode effect in melon by −86% and −79%, respectively. Repeated solarization treatments also resulted in a high reduction of emergence of most weed species in all crop cycles. A single soil solarization treatment was shown to be effective for a long-term sustainable management of weeds, whereas the time-limited effectiveness against root-knot nematodes can be enhanced through two- or three-year repeated treatments.

Methodological Challenges of Symptom Management Research in Recurrent Cancer

Completion of first-line treatment is an important milestone for adults newly diagnosed with cancer. However, for many adults, the cancer experience of the 21st century does not end with the completion of initial treatment. Decreased functional status, distressing symptoms, and residual effects of treatment impact the daily lives of cancer survivors. Cancer has evolved into a chronic illness, in which a disease-free period may be followed by recurrent cancer. Researchers face challenges in the design and analysis of symptom management studies in recurrent disease. Residual effects can preclude a true "baseline" measurement of the symptom(s) of interest to the researcher. In addition, as cancer survivors age, they are more likely to have comorbid conditions that increase the likelihood of developing toxicities and residual symptoms that are specific to cancer treatments. Research studies of cancer-related symptoms in adults with recurrent disease pose many methodological challenges. Selection of appropriate study design, sample inclusion and exclusion criteria, measures of comorbidity and symptoms, and advanced analysis techniques are among the strategies proposed to address these methodological challenges.

Direct and residual effects of agro-industrial wastes on a rocket salad ( Eruca sativa Mill.) — Sorghum [ Sorghum bicolor (L.) Moench] sequence

A field study conducted for two years (2002–04) at New Delhi showed that the seed yield (1.80 t ha −1 ) of rocket salad ( Eruca sativa Mill.) obtained by applying 5 t ha −1 pressmud compost based on distillery effluent + half the recommended dose of NPKS (recommended dose: 60 kg N, 13 kg P, 25 kg K and 20 kg S ha −1 ) was on par with the seed yield (1.69 t ha −1 ) recorded with the recommended dose of NPKS. However, the seed yield recorded with the former treatment significantly exceeded that obtained with 5 t ha −1 of a 1:1 mixture of fly ash and distillery effluent + half the recommended dose of NPKS (by 30.4%) or 5 t ha −1 of dry Jatropha curcas leaves + ½ NPKS (by 24.1%). On average, distillery effluent-based pressmud compost + ½ NPKS induced a perceptible increase in the soil-available NPK, recorded after the harvest of rocket salad, compared to the initial fertility status. The uptake of NPKS in the seed and stover of rocket salad was the highest after the application of pressmud compost, closely followed by the recommended dose of NPKS, and the lowest in the control. The residual effect of treatments given to rocket salad was significant on the fodder yield of succeeding sorghum [ Sorghum bicolor (L.) Moench]. The fodder yield recorded with pressmud compost + ½ NPKS was significantly higher than the other treatments. The application of pressmud compost alone was also significantly superior to the same rate of fly ash + effluent mixture or dry Jatropha leaves with respect to the seed yield of rocket salad, residual fertility after the harvest of rocket salad and the fodder yield of succeeding sorghum.

Plasma sangüíneo em pó em dietas para leitões desmamados aos 14 dias de idade

Foi conduzido um experimento utilizando 128 leitões com peso inicial de 4,32 ± 0,55 kg, desmamados aos 14 dias de idade, distribuídos em delineamento em blocos, composto de quatro tratamentos, oito repetições e quatro animais por unidade experimental, com o objetivo de avaliar níveis de inclusão de plasma sangüíneo em pó (PSP) em dietas para leitões em três períodos consecutivos: 14 a 28 (período 1); 29 a 35 (período 2) e 36 a 42 (período 3) dias de idade. Os níveis de PSP foram de 0,0; 4,0; 6,0 e 8,0% para o período 1; 0,0; 2,8; 4,2 e 5,6% para o período 2 e 0,0; 2,0; 3,0 e 4,0% para o período 3. No período 4 (43 a 56 dias de idade), todos os leitões foram alimentados com dieta isenta de PSP. Durante o período 1, o consumo diário de ração (CDR) e o ganho de peso diário (GPD) foram afetados de forma linear crescente pelos níveis de PSP, entretanto, o modelo Linear Response Plateau foi o que melhor se ajustou aos dados; a partir dele, estimaram-se os níveis de 7,5% de PSP para CDR e de 6,6% para GPD. No período 2, os níveis de PSP não influenciaram essas características de desempenho. No período 3, verificou-se efeito dos níveis de PSP sobre o GPD, que diminuiu de forma linear a medida que os níveis PDP aumentou. Entretanto, não foi constatada diferença no CDR entre os níveis de PSP. Não houve efeito residual dos níveis de PSP sobre o CRD e o GPD no período 4. O nível de inclusão de PSP na dieta de leitões desmamados aos 14 dias de idade é de 7,5% para o período de 14 a 28 dias de idade dos animais.

Sustaining productivity of wheat–soybean cropping system through integrated nutrient management practices on the Vertisols of central India

Wheat–soybean is one of the most dominant cropping systems on the Vertisols of central India. Cultivation of durum wheat in winter season (November to April) has a considerable potential due to congenial climate, while soybean in rainy season (June to October) has witnessed a phenomenal growth in the last two decades in the region. Beside including a legume (soybean) in sequence with a cereal crop (wheat), combined use of available organic sources along with chemical fertilizers may prove beneficial for long-term productivity and sustainability of the system. A long-term experiment was conducted during 1995–2000 on the fine-textured Vertisols at Indore, India to study the effect of combined use of farmyard manure (FYM), poultry manure, vermicompost and biofertilizers (Azotobacter + phosphate solubilizing bacteria) with 0.5 and 1.0 NPK (120 kg N + 26.2 kg P + 33.3 kg K ha−1) on wheat, and residual effect on following soybean. Grain yield of aestivum wheat in the initial 2 years and durum wheat in the later 3 years was significantly increased with 0.5 NPK + poultry manure at 2.5 t ha−1 or FYM at 10 t ha−1 compared with 0.5 NPK alone, and was on par with 1.0 NPK. However, the highest productivity was obtained when these organic sources were applied along with 1.0 NPK. Quality parameters of durum wheat viz protein content, hectolitre weight and sedimentation value showed improvement, and yellow berry content was significantly lower with combined use of NPK + organic sources compared with NPK alone and control. Soybean did not show much response to residual effect of nutrient management treatments applied to wheat. Wheat gave higher profit than soybean, particularly in the later years due to lower grain yields and market price of soybean. However, the superiority of FYM as well as poultry manure along with 1.0 NPK was evident on the overall profitability of the system. Various soil fertility parameters including chemical and biological properties showed conspicuous improvement over the initial status under the treatments of FYM and poultry manure. Sustainability yield index was maximum under 1.0 NPK, followed by 1.0 NPK + poultry manure or FYM. It was concluded that application of available organic sources, particularly FYM and poultry manure along with full recommended dose of NPK fertilizers to wheat was essential for improving productivity, grain quality, profitability, soil health and sustainability of wheat–soybean system.

Echocardiographic Evidence of Left Atrial Mechanical Dysfunction after Conversion of Atrial Fibrillation to Sinus Rhythm in 5 Horses

Background: Atrial contractile dysfunction occurs in some species after conversion of atrial fibrillation (AF) to normal sinus rhythm (NSR) but has not been reported in horses with naturally occurring AF. Hypothesis: Transthoracic echocardiography allows detection of left atrial (LA) mechanical dysfunction in horses after conversion of AF to NSR. Animals: Five Standardbreds with AF and 6 healthy Standardbreds of similar age, weight, and athletic condition were included in this study. Methods: Four horses were treated pharmacologically (quinidine), and 1 horse was treated by means of transvenous electrical cardioversion. Echocardiographic examinations were performed in normal horses (once) and in AF horses (24 hours and 72 hours after conversion to NSR) by means of 2‐dimensional echocardiography (2DE), transmitral flow Doppler, and tissue Doppler imaging (TDI) techniques. Echocardiographic indices of LA mechanical function were compared between normal horses and AF horses. Results: Two‐dimensional echocardiography and TDI indices of LA mechanical function revealed significant decreases in LA contractile function and LA reservoir function 24 hours after cardioversion. This decrease was no longer statistically significant 72 hours after cardioversion, but changes in echocardiographic variables between 24 and 72 hours varied among horses. Conclusions and Clinical Importance: LA contractile dysfunction can be evaluated in horses by use of 2DE, transmitral Doppler flow velocity profiles, and analyses of LA wall motion by TDI. The results of this study are consistent with AF‐induced atrial remodeling, although residual treatment effects or influence of underlying primary myopathy cannot be excluded.

Breast-feeding After Breast Cancer in Childbearing Women

According to the American Cancer Society in 2007, about 178,000 women are diagnosed with breast cancer each year in the United States. Of these, 25% have tumors in their childbearing years and may desire future opportunities for pregnancy and lactation. Although there is a multitude of options related to preserving fertility, little is known about the residual effects of breast cancer treatment and the ability to breast-feed afterward. This article describes the epidemiological relationship between breast cancer and pregnancy and lactation. Basic types of treatment for breast cancer including surgery, chemotherapy, and radiation are reviewed. Practical information on how to support breast-feeding after breast cancer is included.

Tumor response to chemotherapy as a surrogate endpoint of survival in advanced non-small cell lung cancer (NSCLC): Results of an individual patients data meta-analysis

7548 Background: In order to assess the validity of objective response to chemotherapy (CT) as a surrogate endpoint of survival in advanced non-small cell lung cancer (NSCLC), we applied the four Prentice criteria to the data collected in the CISCA meta-analysis, comparing the efficacy of carboplatin and cisplatin in the first-line treatment of advanced NSCLC. Methods: Nine trials including 2,968 patients (pts) were analyzed in the CISCA meta-analysis. The prognostic effect of tumor response on survival was analyzed setting a landmark at two months after randomization (time of response recording), in order to eliminate early death from the analysis. After this landmark correction, pts included in the validation analysis were 2,525 with complete data on tumor response and survival. Results: Cisplatin-based CT was associated with a significantly higher tumor response rate compared with carboplatin-based CT (OR = 1.39; 95% CI: 1.18–1.64; p &lt; 0.001). Carboplatin regimens also led to a numerically higher risk of death as compared to cisplatin (HR = 1.06; 95% CI: 0.98–1.16; p = 0.15). Tumor response was a highly significant predictor of survival (HR = 0.50; 95% CI: 0.46–0.55; p &lt; 0.001). When tumor response was introduced in the Cox model (as a four level variable), the hazard ratio in favour of cisplatin treatment changed from 1.06 to 1.004 (95% CI: 0.922–1.093; p = 0.94), indicating that no residual effect of the cisplatin treatment on survival was present once tumor response was adjusted for. This suggests that the overall survival benefit of cisplatin CT was a result of the increase in response rate. The median survival time of patients with complete and partial response was 19.5 months (95% CI: 11.5–27.5 months) and 14.0 months (95% CI: 13.1–14.9 months), respectively; whereas, the median survival time of patients with no response was 7.8 months (95% CI: 7.5–8.1 months). Conclusions: These results support the hypothesis that the achievement of an objective response to CT in advanced NSCLC is associated with a survival benefit. The potential role of objective response as a surrogate endpoint for survival in CT trials of advanced NSCLC warrants further investigation. No significant financial relationships to disclose.

A review of uniform cross-over designs

Uniform cross-over designs form an important family of experimental designs. They have been applied in many scientific disciplines including clinical trials, agricultural studies and psychological experiments. In this paper we consider the four types of uniform cross-over design, as given by Williams [1949. Experimental designs balanced for the estimation of residual effects of treatments. Aust. J. Sci. Res. 2, 149–168], Cheng and Wu [1980. Balanced repeated measurements designs. Ann. Statist. 8, 1272–1283. Corrigendum 11 (1983) 349], Bate and Jones [2006. The construction of nearly balanced and nearly strongly balanced uniform cross-over designs. J. Statist. Plann. Inference 136, 3248–3267] and Kunert [1983. Optimal design and refinement of the linear model with applications to repeated measurements designs. Ann. Statist. 11, 247–257]. The efficiency of these designs, existence criteria and methods of construction are described.

Rehabilitation versus drug therapy for urge urinary incontinence: long-term outcomes

The objective of this study was to compare the residual effect of a 3-month rehabilitation treatment and a standard drug treatment for urge urinary incontinence (UUI) 21 months post intervention. Forty-four women (ages 27-68 years) who were diagnosed with overactive bladder (OAB) were divided into 2 treatment groups over 3 months: 24 women received rehabilitation (REH) and 20 women were treated with medication (MED) (oxybutynin ER). Outcomes measures included frequency of urination, quality of life (QoL), and number of side effects (no/SE), which were measured upon entry into the study (entry), completion of the intervention (3 months), and at follow-up 3 and 21 months after completion of treatment. In the follow-up period, there was a significant group-time interaction effect on freq/day and freq/night (p < 0.01). At the end of follow-up, the mean number of no/SE was significantly greater in the MED group compared to the REH group (3.3 +/- 0.5 vs 2.4 +/- 0.4; p < 0.05). A significant negative association was found between the urinary symptoms and the I-QoL at the 21-month follow-up (r (p) = -0.45 to-0.57, p < 0.05). In the long-term, the REH patients maintained and even improved the achievements of the intervention period while the MED patients deteriorated to baseline values in urinary frequency. The suggestion for future work is to investigate the effect of each REH treatment component on UUI symptoms.

Residual fertilizer effects on dry‐matter yield and nutritive value of Mediterranean pastures

SummaryFive pastures in an Mediterranean environment in southern Italy were fertilized for 6 years (1993–1998) with nitrogen (N) fertilizer, phosphorus (P) fertilizer and two levels low (L) and high (H) of combined nitrogen and phosphorus fertilizer (N‐P), and compared with a no‐fertilizer control treatment, and the effects on soil variables, dry matter (DM) yield of herbage and floristic composition of the pastures measured. From 1998–2002, half of each plot was fertilized with the same treatments (continued treatment) while the other half received no fertilizer (discontinued treatment). In the year 2001–2002, the plots on the discontinued fertilizer treatments and the plots on the control treatment were used to evaluate the residual effects of the fertilizer treatments. The P and N‐P fertilizer continued and discontinued treatments, in comparison to the control treatment, had a higher content of available P2O5 in the soil while under the N fertilizer treatment it decreased. The N and P fertilizer treatments and the residual effects of these treatments led to higher DM yields and proportions of Gramineae and Leguminosae, respectively, compared to the control treatment. Furthermore, differences in the nutritive value of the herbage and floristic composition were observed between the N‐P fertilizer treatments and the control treatment. The residual effect of the N, P and N‐P fertilizer treatments increased DM yield proportionately by 0.063, 0.385 and 0.404, respectively, and reduced the crude protein content of the herbage. The residual effects of the fertilizer treatments on milk forage units (MFU) were 261 for N, 1107 for P and 1003 MFU ha−1 for N–P fertilizer treatments. Among fertilizers, the residual effect of the N‐P fertilizer treatment promoted an increase in DM yield but produced little variation in floristic composition of the pasture. In general, the fertilizer treatments increased DM yield and nutritive value of herbage and reduced floristic composition in pastures on these Mediterranean sites.

Balanced residual treatment effects designs of first order for correlated observations

Gill [1992. Balanced change-over designs for autocorrelated observations. Austral. J. Statist. 34(3), 415–420] discussed change-over designs of first-order residual treatment effects and obtained conditions for a design to be variance-balanced, which is uniform over periods and binary over subjects, in the presence of autocorrelated errors. In this paper, some new variance-balanced residual treatment effects designs of first order are constructed in the presence of autocorrelated errors that satisfy the conditions given in Gill [1992. Balanced change-over designs for autocorrelated observations. Austral. J. Statist. 34(3), 415–420].

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Echocardiographic Evidence of Left Atrial Mechanical Dysfunction after Conversion of Atrial Fibrillation to Sinus Rhythm in 5 Horses

Atrial contractile dysfunction occurs in some species after conversion of atrial fibrillation (AF) to normal sinus rhythm (NSR) but has not been reported in horses with naturally occurring AF. Transthoracic echocardiography allows detection of left atrial (LA) mechanical dysfunction in horses after conversion of AF to NSR. Five Standardbreds with AF and 6 healthy Standardbreds of similar age, weight, and athletic condition were included in this study. Four horses were treated pharmacologically (quinidine), and 1 horse was treated by means of transvenous electrical cardioversion. Echocardiographic examinations were performed in normal horses (once) and in AF horses (24 hours and 72 hours after conversion to NSR) by means of 2-dimensional echocardiography (2DE), transmitral flow Doppler, and tissue Doppler imaging (TDI) techniques. Echocardiographic indices of LA mechanical function were compared between normal horses and AF horses. Two-dimensional echocardiography and TDI indices of LA mechanical function revealed significant decreases in LA contractile function and LA reservoir function 24 hours after cardioversion. This decrease was no longer statistically significant 72 hours after cardioversion, but changes in echocardiographic variables between 24 and 72 hours varied among horses. LA contractile dysfunction can be evaluated in horses by use of 2DE, transmitral Doppler flow velocity profiles, and analyses of LA wall motion by TDI. The results of this study are consistent with AF-induced atrial remodeling, although residual treatment effects or influence of underlying primary myopathy cannot be excluded.