bluuebunny/crossref_metadata_2025_split huggingface dataset:
Germination ecology of Leptochloa chinensis: a new weed in the Italian rice agro‐environment
Authors: Benvenuti S , Dinelli G , Bonetti A 
Published: March 2004

Summary Leptochloa chinensis is a new weed that has been found with increasing frequency in Italian rice paddies. The germination ecology of L. chinensis seeds was studied in order to investigate the development mechanisms and survival strategy of this weed in rice paddies of northern Italy. Leptochloa chinensis seeds showed no dormancy and exhibited germination even in anoxic conditions. Germination was strongly influenced by temperature (minimum around 15°C; optimal 25–35°C) and light (phytochrome dependent). Temperature fluctuation caused an increase of seed germination in the dark. Seed burial also strongly inhibited germination and emergence of this species. At 5 cm seed burial only 5% of seedlings emerged in flooded conditions, while at the same depth, but with no flooding, no seedling emergence was observed. This phenomenon was not due to oxygen depletion, as germination was not inhibited by complete anoxia, as demonstrated by the fact that some seedlings did emerge in flooding conditions when water was no deeper than 6 cm. Seed burial and concomitant flooding induced an unusual germination: first coleoptile emergence and subsequently emergence of the radicle was observed. The possible exploitation of this knowledge for weed management is discussed.
Relative contribution of genotype, seed size and environment to secondary seed dormancy potential in Canadian spring oilseed rape (Brassica napus)
Authors: Gulden R H , Thomas A G , Shirtliffe S J 
Published: March 2004

SummarySecondary seed dormancy has been linked to seedbank persistence of volunteer oilseed rape (Brassica napus) in western Canada. It has been suggested that there is a genetic component to secondary seed dormancy expression in oilseed rape, but little is known of its importance in relation to non‐genetic factors. In a series of experiments we investigated the relative importance of genotype, seed size, time of windrowing and pre‐ and post‐harvest environment on the expression of secondary seed dormancy. We found that genotype contributed between 44 and 82% to the total variation in secondary seed dormancy. A broad range in secondary seed dormancy expression was observed among 16 genotypes examined. Nevertheless, three‐quarters of the genotypes investigated exhibited relatively high potential for the expression of secondary seed dormancy (back‐transformed mean 71% dormant seeds). Seed size contributed 21% to the total variation, while the influence of seed maturity (harvest regime) on secondary seed dormancy expression was negligible. Despite diverging environmental conditions during the four growing seasons spanning these experiments, the influence of pre‐harvest environment on seed dormancy expression was relatively small and ranged from 0.1% to 4.5%. Secondary seed dormancy potential decreased over time during seed storage. This decrease was greatest when seeds were stored at ambient temperatures and least when seeds were stored at −70°C.
Biocontrol options for Cirsium arvense with indigenous fungal pathogens
Authors: Guske S , Schulz B , Boyle C 
Published: March 2004

SummaryAs a first step in the development of a mycoherbicide for biological control of Cirsium arvense indigenous fungal pathogens that had been isolated from diseased hosts were tested both singly and in combination on potted plants under environmental conditions. Disease symptoms (necroses, chloroses and macerations) and parameters of growth and development were evaluated to determine the potential for weed control. During 1998, Phoma destructiva, Phoma hedericola, a Mycelia sterilia and Puccinia punctiformis were inoculated singly. With the exception of the obligate biotroph P. punctiformis (local infections), the single inoculations reduced the measured parameters. A combined inoculum of P. punctiformis and Ph. hedericola was less effective than Ph. hedericola alone. In 1999, Ph. hedericola, Ph. destructiva, Ph. nebulosa and the Mycelia sterila were applied both singly and as a combined inoculum. Of all the tested inocula, the mixture of four pathogens had the greatest potential for biocontrol, significantly reducing reproductive capacity of the plants. These results demonstrate the importance of taking advantage of synergisms in developing a mycoherbicide.
Reduced rates of residual and post‐emergence herbicides for weed control in vineyards
Authors: Monteiro A , Moreira I 
Published: March 2004

SummaryIn 1997 and 1998, five field studies were conducted at four Portuguese wine‐growing regions in order to evaluate the effectiveness of the chemical control of vineyard weeds under Mediterranean conditions using either reduced doses of residual herbicides or only foliar herbicides. Amitrole (3440 g a.i. ha−1), amitrole + glyphosate mono‐ammonium salt (1720 + 900 g a.i. ha−1), amitrole (3400 g a.i. ha−1), amitrole + diuron (2580 + 1500 g a.i. ha−1), amitrole + simazine (2580 + 1500 g a.i. ha−1), amitrole + terbuthylazine (2580 + 1500 g a.i. ha−1) and amitrole + diuron + simazine (2580 + 1300 + 1400 g a.i. ha−1) were assayed and compared with the following reference herbicides: glyphosate isopropylamine salt (1800 g a.i. ha−1), amitrole + diuron (2520 + 1680 g a.i. ha−1), diuron + glyphosate + terbuthylazine (1275 + 900 + 1425 g a.i. ha−1), amitrole + simazine (1900 + 3900 g a.i. ha−1) and glyphosate + simazine (800 + 2200 g a.i. ha−1). The herbicides were applied during late winter. The results indicated that good control was achieved by the application of foliar herbicides alone or of reduced rates of a mixture of residual herbicides with foliar herbicides for at least 2 months. Three months after application, the efficacy of post‐emergence herbicides and lower rates of residual herbicides decreased significantly in clay soils and under heavy rainfall conditions. Convolvulus arvensis– a weed that is becoming increasingly significant in Portuguese vineyards – was poorly controlled, even when glyphosate was used. Despite this, it can be assumed that in those regions in which the trials were conducted, it is possible to employ weed control strategies that entail the elimination or a reduction in the rate of residual herbicides.
Genetic structure of the invasive Chromolaena odorata in China
Authors: Ye W H , Mu H P , Cao H L , Ge X J 
Published: March 2004

Summary Chromolaena odorata is one of the world's worst tropical weeds, and it can be found in Guangdong, Guangxi, Hainan and Yunnan provinces in China. Genetic variation of 27 C. odorata populations sampled from across its invasive range in China was investigated using inter‐simple sequence repeats (ISSR) analysis. All populations exhibited low levels of genetic variation. On average, 2.35% of the ISSR loci were polymorphic, total genetic diversity (HT) was 0.0406 and Shannon's information index (Hsp) was 0.0623. High genetic identities (I) between populations (0.9687 ± 0.01204) indicated low genetic differentiation. A frequent founder effect was interpreted as the main cause of the genetic structure observed in C. odorata.
Development of microsatellite markers and their effectiveness in Lolium temulentum
Authors: Senda T , Kubo N , Hirai M , Tominaga T 
Published: March 2004

SummaryScreening a genomic library of Lolium temulentum (darnel) with synthetic (GT)15 and (GA)15 oligonucleotides, we identified microsatellite‐containing clones. Based on the sequence data of the clones, specific primer pairs were synthesized and their effectiveness examined using 10 L. temulentum and two L. persicum accessions from Asia, Africa and Europe. Fifteen primer pairs amplified single fragments, and five of them showed polymorphism in polyacrylamide gel electrophoresis in the L. temulentum and L. persicum accessions. Fifteen primer pairs reported in L. perenne (perennial ryegrass) were also applied in this study. Nine of them amplified the microsatellite alleles, and two of the nine showed polymorphic alleles in L. temulentum and L. persicum. For the polymorphic markers, polymorphic information content values ranged from 0.60 to 0.86 with an average of 0.76 among 10 L. temulentum accessions. The microsatellite markers developed for L. temulentum and L. perenne should be informative and powerful in analysing the intraspecific genetic diversity and the phylogenetic relationships of L. temulentum and L. persicum.
Recovery of non‐target plants affected by airborne bromoxynil‐octanoate and metribuzin
Authors: Follak S , Hurle K 
Published: March 2004

SummaryThe present study was conducted to evaluate the recovery potential of non‐target plants affected by two airborne herbicides. Sunflower at the two‐leaf stage was used as a test plant and exposed for 24 h in a wind tunnel to a range of concentrations of airborne bromoxynil‐octanoate and metribuzin. Quantum yield (φPSII) of exposed leaves and of the second leaf pair developed after exposure was determined at a particular time up to 16 days following exposure. Maximum depression in quantum yield of exposed leaves from which a complete recovery occurred within 16 days was 63% for bromoxynil‐octanoate and 60% for metribuzin respectively. The corresponding maximum concentrations were 1.310 and 0.390 μg m−3 respectively. The second leaf pair was also affected and showed a similar recovery potential. From the results it can be concluded that the significance of airborne bromoxynil‐octanoate and metribuzin must not be overestimated, as sunflower and non‐target plants with a similar sensitivity are likely to recover from air concentrations of both herbicides reported under field conditions.
Non‐alcoholic steatohepatitis in the Asia–Pacific region: Future shock?
Authors: CHITTURI SHIVAKUMAR , FARRELL GEOFFREY C , GEORGE JACOB 
Published: March 2004

AbstractClinicians in both the developed and also the newer industrial economies in the Asia–Pacific region will encounter non‐alcoholic fatty liver disease (NAFLD) with increasing frequency. Although the region has been a significant contributor to the current state of knowledge, the spectrum of NAFLD, its severity and the potential for significant future morbidity and health costs are not widely recognized. Lifestyle changes, the epidemic of childhood and adult obesity and type 2 diabetes sweeping the Asia–Pacific represent the key substrates for the rising prevalence of NAFLD. Physicians in all disciplines need to be aware of clinical clues to the presence of NAFLD in the absence of other liver disease and in those with chronic viral hepatitis and they should be able to identify subsets at risk for liver‐related morbidity. Given the scope of the problem, efforts should focus primarily on preventing or ameliorating the impact of risk factors; the key one is insulin resistance and its associates of diabetes and central obesity. Pharmacotherapy may play a role in selected individuals. A regional agenda for case definition, future study and public health initiatives is urgently required.
Low prevalence of Helicobacter pylori but high prevalence of cytomegalovirus‐associated peptic ulcer disease in AIDS patients: Comparative study of symptomatic subjects evaluated by endoscopy and CD4 counts
Authors: CHIU HAN‐MO , WU MING‐SHIANG , HUNG CHIEN‐CHING , SHUN CHIA‐TUNG , LIN JAW‐TOWN 
Published: March 2004

AbstractBackground and Aims:  The role of Helicobacter pylori infection in gastroduodenal lesions might be different between the general population and AIDS patients. The aim of the present study was to compare the prevalence of H. pylori and cytomegalovirus (CMV) infection in AIDS patients and HIV‐negative controls. The impact of CD4 lymphocyte counts on H. pylori and CMV infection in the same subjects was also assessed.Methods:  One hundred and fifty‐six patients (52 HIV‐positive, 104 HIV‐negative) with gastrointestinal symptoms were evaluated with upper gastrointestinal endoscopy and biopsy. Comparison of the prevalence of H. pylori and CMV infection was made by dividing AIDS patients into two groups: those with CD4 counts >100/mm3 and those with CD4 counts <100/mm3, and ulcer and non‐ulcer patients.Results:  In comparison with HIV‐negative controls, AIDS patients had a lower prevalence of H. pylori infection (P < 0.0001) but a higher prevalence of CMV infection (P < 0.0001). Cytomegalovirus infection was frequently found in AIDS patients with CD4 count <100/mm3, in comparison with those with a CD4 count >100/mm3. In AIDS patients, CMV was more frequently detected in subjects with peptic ulcers (P = 0.0125). Conversely, the prevalence of H. pylori infection in AIDS patients was not different between those with and without peptic ulcers.Conclusions:  The low prevalence of H. pylori infection and peptic ulcer in AIDS patients suggests a different role of H. pylori infection in peptic ulcer or even a different mechanism of peptic ulcerogenesis in HIV‐positive subjects. Cytomegalovirus, rather than H. pylori, may be the main causative pathogen of peptic ulcers in AIDS patients.
Role of zinc in subclinical hepatic encephalopathy: Comparison with somatosensory‐evoked potentials
Authors: YANG SIEN‐SING , LAI YUN‐CHIH , CHIANG TSUEY‐RU , CHEN DER‐FANG , CHEN DING‐SHINN 
Published: March 2004

AbstractBackground and Aim:  The purpose of the present paper was to determine the role of zinc in subclinical portosystemic encephalopathy (SPSE).Methods:  The serum zinc levels were studied for 10 cirrhotic patients who did not suffer SPSE and for 10 patients who did, and the results compared with those deriving from 10 healthy volunteers. The nutritional evaluation included serum prealbumin, albumin, and transferrin levels, body mass index (BMI), mid‐arm muscle circumference (MAMC), and tricep skin‐fold (TSF). The occurrence of SPSE was defined as a situation when the N20–N65 interpeak latencies of median nerve‐stimulated somatosensory‐evoked potentials (SEP) exceeded 2.5 SD of the control mean value.Results:  Cirrhotic patients suffering SPSE (57.5 ± 10.5 µg/dL) had lower serum zinc levels than those not experiencing SPSE (69.5 ± 16.6 µg/dL, P = 0.03) and controls (77.7 ± 6.8 µg/dL, P < 0.001). Four of the non‐SPSE and nine SPSE patients had zinc levels less than the lower normal limit. Cirrhotic patients suffering SPSE had lower levels of albumin (2.8 ± 0.4 g/dL vs 3.8 ± 0.4 g/dL, P < 0.001), prealbumin (9.0 ± 4.3 mg/dL vs 14.3 ± 6.0 mg/dL, P = 0.02), and transferrin (158 ± 56 g/L vs 218 ± 50 g/L, P = 0.01), but a greater total bilirubin level (1.2 ± 1.5 mg/dL vs 0.9 ± 0.4 mg/dL, P = 0.005) than those not suffering SPSE. The serum zinc levels correlated with N20–N65 interpeak latencies (P = 0.03), serum albumin (P = 0.006), prealbumin (P < 0.001), and total bilirubin (P = 0.02) levels.Conclusions:  The data show that zinc deficiency is common in cases of non‐alcoholic cirrhosis with SPSE. The early assessment of malnutrition and zinc deficiency are important.
Endoscopic balloon dilatation of benign gastric outlet obstruction
Authors: KOCHHAR RAKESH , SETHY PRADEEPTA KUMAR , NAGI BIRENDER , WIG JAY DEV 
Published: March 2004

AbstractBackground and Aim:  Endoscopic balloon dilatation (EBD) has been used for the treatment of gastric outlet obstruction (GOO). There are several reports on the utility and success of this non‐surgical treatment option in peptic GOO, with variable results. However, there are only a few reports documenting the efficacy of this method for non‐peptic GOO. The authors here report on experience with balloon dilatation in peptic and non‐peptic GOO over a 3‐year period.Methods:  Twenty‐three patients with benign GOO underwent EBD. Dilatation was carried out with through‐the‐scope balloon dilators after premedication. Dilatation was repeated every week and the response was documented on the basis of symptoms and endoscopic findings and barium studies. Helicobacter pylori was eradicated in patients with peptic GOO, when present.Results:  The 23 patients with GOO included 11 with peptic ulcer as the etiology, eight with corrosive‐induced and four with chronic pancreatitis (alcohol three, idiopathic one). Patients with peptic GOO required 1–3 sessions (mean 2.0 ± 0.63) to achieve a diameter of 15 mm dilatation, with uniformly good response over a mean follow‐up period of 14.04 ± 9.79 months. Corrosive‐induced GOO required a larger number of dilatation sessions (2–9, mean 5.63 ± 2.88), but the response was equally good, with follow up of 12–30 months. Patients with pancreatitis‐related GOO, however, failed to respond despite a mean of 5.50 (±0.58) dilatations, and continued to have symptoms. All these patients were subjected to surgical bypass. There were no major complications such as perforation.Conclusions:  A good response can be expected in the majority of patients with peptic and corrosive‐related GOO after balloon dilatation; however, poor results are noted for chronic pancreatitis‐related GOO.
Report of the Asia–Pacific consensus on the management of gastroesophageal reflux disease
Authors: FOCK KWONG MING , TALLEY NICK , HUNT RICHARD , FASS RONNIE , NANDURKAR SANJAY , LAM SHIU‐KUM , GOH KHEAN LEE , SOLLANO JOSE 
Published: March 2004

AbstractThis report summarizes the conclusions and recommendations of a panel of gastroenterologists practising in the Asia–Pacific region. The group recognized that although gastroesophageal reflux disease (GERD) is less common and milder in endoscopic severity in Asia than in the West, there is nevertheless data to suggest an increasing frequency of the disease. During a 2‐day workshop, the evidence for key issues in the diagnosis and clinical strategies for the management of the disease was evaluated, following which  the  recommendations  were  made  and  debated.  The  consensus  report  was  presented  at  the Asia–Pacific Digestive Week 2003 in Singapore for ratification. Upper gastrointestinal (GI) endoscopy is the gold standard for the diagnosis of erosive GERD. There is no gold standard for the diagnosis of non‐erosive GERD (NERD). Diagnosis therefore relies on symptoms, a positive 24‐h pH study or a response to a course of proton pump inhibitor (PPI) treatment. The goals of treatment for GERD are to heal esophagitis, relieve symptoms, maintain the patient free of symptoms, improve quality of life and prevent complications. The PPI are the most effective medical treatment. Following initial treatment, on‐demand therapy may be effective in some patients with NERD or mild (GI) erosive esophagitis. Anti‐reflux surgery by a competent surgeon could achieve a similar outcome, although there is an operative mortality of 0.1–0.8%. The decision is dependent on the patient's preference and the availability of surgical expertise. Currently, endoscopic treatment should be performed only in the context of a clinical trial. Treatment of patients with typical GERD symptoms without alarm features in primary care could begin with PPI for 2 weeks followed by a further 4 weeks before going to on‐demand therapy.
Autoassociator networks: insights into infant cognition
Authors: Sirois Sylvain 
Published: March 2004

AbstractThis paper presents autoassociator neural networks. A first section reviews the architecture of these models, common learning rules, and presents sample simulations to illustrate their abilities. In a second section, the ability of these models to account for learning phenomena such as habituation is reviewed. The contribution of these networks to discussions about infant cognition is highlighted. A new, modular approach is presented in a third section. In the discussion, a role for these learning models in a broader developmental framework is proposed.
Hebbian learning and development
Authors: Munakata Yuko , Pfaffly Jason 
Published: March 2004

Abstract Hebbian learning is a biologically plausible and ecologically valid learning mechanism. In Hebbian learning, ‘units that fire together, wire together’. Such learning may occur at the neural level in terms of long‐term potentiation (LTP) and long‐term depression (LTD). Many features of Hebbian learning are relevant to developmental theorizing, including its self‐organizing nature and its ability to extract statistical regularities from the environment. Hebbian learning mechanisms may also play an important role in critical periods during development, and in a number of other developmental phenomena.
Modeling developmental transitions in adaptive resonance theory
Authors: Raijmakers Maartje E.J. , Molenaar Peter C.M. 
Published: March 2004

AbstractNeural networks are applied to a theoretical subject in developmental psychology: modeling developmental transitions. Two issues that are involved will be discussed: discontinuities and acquiring qualitatively new knowledge. We will argue that by the appearance of a bifurcation, a neural network can show discontinuities and may acquire qualitatively new knowledge. First, it is shown that biological principles of neurite outgrowth result in self‐organization in a neural network, which is strongly dependent on a bifurcation in the activity dynamics. Second, the effect of a bifurcation due to morphological change is investigated in an Adaptive Resonance Theory (ART) network. Exact ART networks with quantitative differences in network structure at the category level show qualitatively different dynamical regimes, which are separated by bifurcations. These qualitative differences in dynamics affect the cognitive function of Exact ART: Representations of learned categories are local or distributed.
Evolving agents as a metaphor for the developing child
Authors: Schlesinger Matthew 
Published: March 2004

Abstract The emerging field of Evolutionary Computation (EC), inspired by neo‐Darwinian principles (e.g. natural selection, mutation, etc.), offers developmental psychologists a wide array of mathematical tools for simulating ontogenetic processes. In this brief review, I begin by highlighting three of the approaches that EC researchers employ (Artificial Life, evolutionary robotics and comparative stochastic optimization). I then focus on the advantages of using comparative stochastic optimization as a method for studying development. As a concrete example, I illustrate the design and implementation of an EC model that simulates the development of reaching in young infants.
‘Core Knowledges’: a dissociation between spatiotemporal knowledge and contact‐mechanics in a non‐human primate?
Authors: Santos Laurie R. 
Published: March 2004

Abstract Human toddlers demonstrate striking failures when searching for hidden objects that interact with other objects, yet successfully locate hidden objects that do not undergo mechanical interactions. This pattern hints at a developmental dissociation between contact‐mechanical and spatiotemporal knowledge. Recent studies suggest that adult non‐human primates may exhibit a similar dissociation. Here, I provide the first direct test of this dissociation using a search paradigm with adult rhesus monkeys. Subjects watched as a plum rolled behind one of two opaque barriers. In Experiment 1, subjects had to locate the plum based on the position of a wall that blocked the plum's trajectory. Subjects searched incorrectly, apparently neglecting information about the location of the wall. However, subjects searched correctly in Experiments 2–4 when they were given spatiotemporal information about the plum's movement. Results indicate that adult monkeys use spatiotemporal information, but not contact‐mechanical information, to locate hidden objects. This dissociation between contact‐mechanical and spatiotemporal knowledge is discussed in light of developmental theories of core knowledge and the literature on object‐based attention in human adults.