Longer Study Time Research Articles

Modafinil improves antipsychotic-induced parkinsonism but not excessive daytime sleepiness, psychiatric symptoms or cognition in schizophrenia and schizoaffective disorder: A randomized, double-blind, placebo-controlled study

ObjectiveTo examine the efficacy and safety of modafinil on parkinsonism and excessive daytime sleepiness (EDS), as well as on negative symptoms and cognitive abilities in patients with schizophrenia or schizoaffective disorder (DSM-IV criteria) in a randomized double-blind placebo-controlled 8-week study. MethodsTwenty-four male patients, who were aged 20–63years and on stable dose of second generation antipsychotic medications and with a negative symptom score of ≥20 on the Positive and Negative Syndrome Scale (PANSS), were randomized into either the modafinil (n=12) or placebo (n=12) group. The modafinil group received flexible does of modafinil 50–200mg/day. Primary measurements were the Simpson-Angus Scale (SAS) for extrapyramidal side effects (EPS), the Epworth Sleepiness Scale (ESS), the PANSS and a neuropsychological (NP) test battery. Data were collected on Days 0, 14, 28, 42 and 56 for rating scales, and on Days 0, 28 and 56 for NP tests. ResultsMixed model analyses showed a significant group-x-time interaction for total SAS scores (P<0.006), with scores decreasing in the modafinil group but remaining the same in the placebo group. There were no significant group-x-time interactions for scores of ESS (total), PANSS (total, positive and negative), and NP tests (composite and domains) (all P's>0.5). No significant adverse events were observed. ConclusionThe data suggest that modafinil was a safe adjunctive treatment which improved parkinsonian symptoms and signs in patients with schizophrenia or schizoaffective disorder. Further studies in larger samples and with longer study time are needed to test/confirm the beneficial effects of modafinil on motor function.

Assessing the efficacy of hair snares as a method for noninvasive sampling of Neotropical felids

Hair snares have been used in North and Central America for a long time in assessment and monitoring studies of several mammalian species. This method can provide a cheap, suitable, and efficient way to monitor mammals because it combines characteristics that are not present in most alternative techniques. However, despite their usefulness, hair snares are rarely used in other parts of the world. The aim of our study was to evaluate the effectiveness of hair snares and three scent lures (cinnamon, catnip, and vanilla) in the detection of felids in one of the largest remnants of the Brazilian Atlantic Forest. We performed tests with six captive felid species - Panthera onca (Linnaeus, 1758), Leopardus pardalis (Linnaeus, 1758), L. tigrinus (Schreber, 1775), L. wiedii (Schinz, 1821), Puma concolor (Linnaeus, 1771), and P. yagouaroundi (É. Geoffroy Saint-Hilaire, 1803) - to examine their responses to the attractants, and to correlate those with lure efficiency in the field. The field tests were conducted at the Parque Estadual Pico do Marumbi, state of Paraná, Brazil. Hair traps were placed on seven transects. There were equal numbers of traps with each scent lure, for a total of 1,551 trap-days. In captivity, vanilla provided the greatest response, yet no felids were detected in the field with any of the tested lures, although other species were recorded. Based on the sampling of non-target species, and the comparison with similar studies elsewhere, this study points to a possible caveat of this method when rare species or small populations are concerned. Meanwhile, we believe that improved hair snares could provide important results with several species in the location tested and others.

Asthma and paracetamol: Could we really know what happens between them?

An association between paracetamol use or exposure in different times of life, including gestation and childhood, and asthma has been observed in recent years. Causality cannot be established from observational studies because of the arguable presence of many confounding factors and biases. Randomised trials are needed to disclose the nature of the association, but are difficult to carry out because of ethic, economic and logistical issues as large patient samples should be involved for a long time in such studies. Pragmatic trials may be the best option to shed some light on this issue. Questions regarding the problems and difficulties of conducting such trials and the way to overcome them are discussed.

Oak regeneration in southeastern bottomland hardwood forest

Oaks ( Quercus spp.), such as cherrybark oak ( Quercus pagoda Raf.), are valuable timber species in bottomland hardwood (BLH) forests of the southeastern U.S. Oak regeneration is affected by plant flooding tolerance; wind disturbances or forest harvests; and interactions with seed predators and herbivores. We investigated oak regeneration (seedling establishment and early growth, composition of seedling and sapling banks) in experimental openings, from 7 to 40 m radius, created by group-selection harvest in a BLH forest. Seed dispersal, seed predation, and microsite conditions on the forest floor, rather than canopy openness, were the first filters on oak regeneration. In the first 3 years after gap creation, naturally established oak seedlings were most abundant in relatively ‘undisturbed’ microsites with litter cover and around gap edges. Swamp chestnut oak ( Quercus michauxii Nutt.) germination was inhibited in pits, and seedling establishment was greatest under edge or less open canopy. Cherrybark oak seedling establishment and growth were reduced by seed predation and shade. Six years after acorns were planted, swamp chestnut oak seedling height and maximum root depth were greatest in gap centers. Ten years after gap creation, oaks were more abundant beneath the surrounding forest canopy, but were tallest in gap centers. Thus, in contrast to its lack of influence on acorn germination and initial establishment, canopy openness appears to filter oak persistence and height growth in the seedling bank. Forest management that provides level or raised microsites beneath thin canopy and protection from seed predation can facilitate oak seedling establishment in southeastern BLH forests. Maintaining a thin to open canopy can promote oak persistence in the seedling bank; growth into the sapling bank may require reopening the canopy if gap centers have grown up over time. Although longer study time is needed to capture regeneration from seed germination through ascent from the sapling layer into the subcanopy and canopy strata, this large field experiment has revealed there is no optimal gap size for oak regeneration. Rather, biotic interactions, canopy openness, and particularly flood duration at the microsite scale create complex patterns of oak abundance and heights in the seedling and sapling layers following disturbance in bottomland hardwood forests.

Implementing an Objective Structured Clinical Examination (OSCE) in dental education: effects on students’ learning strategies

To investigate the effect of an Objective Structured Clinical Examination (OSCE) on dental students' learning strategies and competence to manage periodontal diseases in patients. The implemented OSCE was expected to be superior to the existing Written Exam in fostering the acquisition of clinical competencies in terms of study strategies that are more oriented towards clinical practice, longer study time, greater clinical proficiency, and more realistic self-assessment. After a clinical course in periodontology, 72 third year dental students were assessed summatively, either using a Written Exam or an OSCE (P-OSCE). The students were informed beforehand about the assessment formats. The self-assessed clinical competence, study time and strategies (i.e. practice with a manikin, peers and patient case) were evaluated by means of a questionnaire. After a comprehensive dental care course, all 72 students were assessed by an overall end-of-year OSCE, in which three periodontal stations were included 'measuring pockets', 'educating patients' and 'tracing an X-ray with bone-loss'. The competence of the previous Written Exam group and the P-OSCE group was investigated by determining the mean scores and pass-fail scores of three periodontal test-stations as well as the total score of the end-of-year OSCE. The degree of realistic self-assessment was studied by correlating the self-assessed competencies as evaluated by means of the questionnaire with the total score of the end-of-year OSCE. Self-assessed clinical competence, study time and study strategies showed no differences between the P-OSCE and the Written Exam-group. The clinical competence determined in the test-station 'measuring pockets' in the end of year overall OSCE was higher for the P-OSCE group (P = 0.05) when compared with the Written Exam group; the two groups performed equally well in the test station 'educating patients', whereas the performance in 'tracing an X-ray with bone-loss' was better in the Written Exam group. This group also had a higher total score in the end-of-year OSCE (P = 0.05). The degree of realistic self-assessment was higher in the P-OSCE group than in the Written Exam group: in the P-OSCE group the self-assessed clinical competencies correlated significantly with the total score of the overall end-of-year OSCE (P < or = 0.05). No effects of the implementation of an OSCE in undergraduate periodontal education were observed in study strategies, but the implementation of an OSCE in undergraduate periodontal education appears to stimulate learning, resulting in greater achievement of specific clinical competence and a greater level of realistic self-assessment.

Accuracy of diagnosis of atypical glandular cells—Conventional and ThinPrep

The incidence of glandular cervical malignancy is steadily increasing. Glandular abnormalities are more frequently diagnosed on cervical smears. In this study, we attempt to evaluate our experience with glandular cytology and to assess the sensitivity and specificity of the ThinPrep (TP) over conventional Papanicolaou (Pap) smears. Glandular abnormalities during a 3-yr period from October 2000 to October 2003 were retrieved from our cytology database. The study group comprised smears from 369 patients, 272 conventional Pap smears (CPSs) and 97 TP from a total of 400,184 smears. The types of glandular abnormalities were tabulated following a modified Bethesda classification. Correlation with histology and follow-up cytology was achieved in all but six patients. Significant lesions were identified in 116/272 (PPV 42.6%) of CPSs and 58/97 (PPV 58.9%) TPs. Pure glandular abnormalities numbered 125 conventional and 51 TP; significant lesions identified in this group were 36/125 (PPV 28.8%) CPS and 26/51 (PPV 50.9%) TP. Statistical analysis showed significant differences for positive predictive values of TP and CPS and a suggestion of increased sensitivity. The main limiting factor was small numbers of glandular abnormalities and a desirable longer study time.

Spin-orbit transition interactions

The spin-orbit two-body interaction has been used for a long time in nuclear structure studies and is unique. In contrast, two different expressions are used in nuclear scattering studies. One of them is stronger when the eigenvalues of $(\ensuremath{\ell}\ifmmode\cdot\else\textperiodcentered\fi{}\ensuremath{\sigma})$ of the two particles involved are opposite to each other, such as the interaction used in nuclear structure studies for an even parity excitation. This expression of the spin-orbit interaction can be qualified as ``normal'' in view of the similar behavior in these two applications. The other expression of the spin-orbit interaction involves the sum of these two eigenvalues.

LİZİMETRELER VE BİTKİ SU TÜKETİMİ ÇALIŞMALARINDA KULLANIMI

Soil water, gained by irrigation and precipitation, is depleted by deep percolation, runoff, evapotranspiration (ET) in the soil-plant-water system. In arid and semi-arid areas, it is essential to determine in advance the ET considering the crop pattern in irrigated land whether the irrigation water source or irrigation system would be sufficient. To know the ET in areas, where irrigation project would be applied, has great importance both for agricultural and civil engineering. A method to evaluate the water budget parameters is isolating crop-soil system from its surrounding area and measuring input and output parameters of the system. Lysimeters defined as a mechanism used to measure change in soil water content during ET, precipitation, irrigation and drainage processes has been used for a long time in hydrological and meteorological studies. In this paper, studies published in international as well as national journals are reviewed and recent popular topics, which were conducted in lysimeters, are examined.

A space-time permutation scan statistic for disease outbreak detection.

BackgroundThe ability to detect disease outbreaks early is important in order to minimize morbidity and mortality through timely implementation of disease prevention and control measures. Many national, state, and local health departments are launching disease surveillance systems with daily analyses of hospital emergency department visits, ambulance dispatch calls, or pharmacy sales for which population-at-risk information is unavailable or irrelevant.Methods and FindingsWe propose a prospective space–time permutation scan statistic for the early detection of disease outbreaks that uses only case numbers, with no need for population-at-risk data. It makes minimal assumptions about the time, geographical location, or size of the outbreak, and it adjusts for natural purely spatial and purely temporal variation. The new method was evaluated using daily analyses of hospital emergency department visits in New York City. Four of the five strongest signals were likely local precursors to citywide outbreaks due to rotavirus, norovirus, and influenza. The number of false signals was at most modest.ConclusionIf such results hold up over longer study times and in other locations, the space–time permutation scan statistic will be an important tool for local and national health departments that are setting up early disease detection surveillance systems.

Psychological effects of occupational exposure to organic solvent mixtures on printers

Purpose: Neuropsychiatric symptoms associated with long-term exposure to organic solvents have been investigated for a long time in many occupational studies. The aim of our study was to identify preclinical effects of low-level chronic solvent exposure on the cognitive performance of silk-screen printers.Methods: A cross-sectional study was conducted including 38 printers which were exposed to organic solvent mixtures and 45 controls without neurotoxic exposure. The psychometric test battery included nine tests and two questionnaires.Results: The sum of scales or the total score of the PNF was also significantly (p < 0.001) higher in the exposed group than in the non-exposed. The printers performed worse in some psychometric tests than did controls. Cross validation with the psychometric performances resulted in 69.6% of participants being correctly classified (55.9% printers and 80% controls). Highly significant differences (p < 0.001) between both groups of exposed and non-exposed workers were found for the mean values of the multidimensional psychometric score.Conclusions: These results of our study proved not only that chronic exposure to organic solvent mixtures could induce a psychological effect but also that the psychological/psychometrical tests performed in this study were capable of predicting neurotoxicity.

Towards a MIP‐based alignment and docking in computer‐aided drug design

Structural alignment of ligands in their biological conformation is a crucial step in the building of pharmacophoric models in structure-based drug design. In addition, docking algorithms are limited in some cases by the quality of the scoring functions and the limited flexibility of the environment that the different programs allow. On the other hand, GRID molecular interaction potentials (MIPs) have been used for a long time in 3D-QSAR studies. However, in most of these studies the alignment of the molecules is performed on the basis of geometrical or physico-chemical criteria that differ from the MIPs used in the partial least squares statistical analysis. We have previously developed a method to use the same scoring function for the molecular alignment and for 3D-QSAR studies. This methodology, based on the use of GRID potentials, consists in the weighted averaging of similarities of the relevant MIPs of the molecules to be aligned. Here we present a method to obtain the weights for the different GRID probes in the average based on the structural information on protein-ligand complexes for relevant systems. The method, implemented in MIPSIM, is shown to yield good accuracy in the prediction of the alignments for two systems: a set of three inhibitors of dihydrofolate reductase and a set of fifteen non-nucleoside HIV-1 reverse transcriptase inhibitors (NNRTIs). The smooth GRID potentials are shown to capture the flexible character of the active site, as opposed to traditional docking scoring energy functions.

Study time effects in recognition memory.

We empirically tested the assumption that study time increases recognition accuracy because the storage of information is better when study time is longer as Shiffrin and colleagues have reported, an assumption common to parallel models of recognition. In the present study with 123 subjects, we examined the effect of item strength on four measures: hit rate, false alarm rate, d', and beta, for a single-word recognition task with longer study times than those usually used in the literature. Analysis indicated significant increase for hit rate and d' and a decrease in false alarm rate, as one goes from weak to stronger study conditions, and a change in ln(beta) when study time is greater than 1 sec. These results suggest that familiarization is one, but not the only, factor underlying the strength-mirror effect.

Traitement du myélome multiple

Conventional chemotherapies are no longer the only treatment in multiple myelomatosis. High-dose chemotherapy and autologous transplantation are not curative but do increase relapse-free survival time in young patients. Thalidomide is efficacious in refractory and relapsing myeloma and its evaluation is going on. Curative and preventive treatments of skeletal events, infections and anemia improve quality of life. All together, these strategies imply therapeutic knowledge and choices but allow an about 5-year long median survival time in modern studies. Treatment options for myeloma now include, not only conventional chemotherapy regimens, but also novel symptomatic drugs and strategies, that increase survival and/or quality of life, although they fail to provide a cure. In parallel with this expansion of the treatment armamentarium, physicians must acquire the knowledge needed to select the best treatment for the individual patient. After reviewing the rationale, effectiveness, and safety of each of these treatments, we will discuss the indications that we believe are legitimate.

Rapporteur Report: Sources and Exposure Metrics for ELF Epidemiology (Part 1)

High quality epidemiological studies on the possible link between exposure to non-ionising radiation and its effects on human health are of great importance for radiation protection. The main sources of ELF fields are domestic appliances, different electrical energy distribution systems, and all types of electrical machinery and devices in the workplace. In general, the ELF fields present in the environment show complex temporal patterns and spatial distributions, depending on the generating source. The complete characterisation of the different field sources often requires highly sophisticated instrumentation, and this is therefore not feasible within the scope of epidemiological studies. On average, indvidual exposure from ELF fields is low in both the working environment and in residential areas. People are subject to significant ELF exposure, with regard to biological effects, only in certain workplaces. Different methods have been developed to determine levels of exposure received by study subjects, with the aim to rank exposed and non-exposed groups in epidemiological studies. These include spot measurements. calculations or modelling. The different methods used to estimate total exposure in epidemiological studies may result, to a differing extent, in a misclassification of the study subjects. Equally important for future studies is the selection of the appropriate exposure metric. The most widely used metric so far is the time-weighted average, which thus represents a quasi standard metric for use in epidemiological studies. In addition, wire codes have been used for a long time in residential studies, and job titles are often used in occuptional studies. On the basis of the experience gained in previous studies, it would be desirable to develop standardised, state-of-the-art protocols to improve exposure assessment. New surrogates and metrics were proposed as the basis for further studies. But only few of these have recently undergone preliminary testing. A favourite candidate is the dB/dt metric. because it is closely related to known biological interactions.

A general survey of molecular quantum similarity

A comprehensive survey of the theoretical foundations and definitions associated with quantum similarity is given. In this task care has been taken to determine the primary mathematical structure which can be associated with quantum similarity measures. Due to this, the concept of a tagged set is defined to demonstrate how molecular sets can be described systematically. The definition of quantum object, a notion introduced by our laboratory and employed for a long time in quantum similarity studies, is clarified by means of a blend involving quantum theory and the tagged set structure formalism, and used afterwards as the cornerstone of the subsequent development of the theory. In the definition of quantum objects, density functions play a fundamental role. To formally construct the quantum similarity measure, it is very interesting to study the main algorithmic ideas, which may serve to compute approximate density forms, accurate enough to be employed in the practical calculation of nuclear, atomic and molecular quantum similarity measures. Thus, the atomic shell approximation is defined accompanied by all the implied computational constraints and the consequences they have in the whole theory development as well as to the physical interpretation of the results. A wide and complex field appears from all these ideas, where convex sets play a fundamental role, and a new definition emerges: one associated with vector semispaces, where the main numerical formalism of quantum similarity seems perfectly adapted. Applications of this development embrace quantum taxonomy, visual representation of molecular sets, QSAR and QSPR, topological indices, molecular alignment, etc., and among this range of procedures and fields, there appears with distinct importance the discrete representation of molecular structures.

The Entrepreneur in Theory and Practice

The entrepreneur, in one form or another, has been around a long time in both economic theory and empirical studies of entry. Argues that these traditions have exhibited an over‐concern with the entrepreneur′s function at the expense of the supply of entrepreneurs, an area which has received only sporadic attention in the literature. It is this supply aspect which is critical to economic development and economists should now devote more attention to it.

Effects induced by high electronic excitations in pure metals: A detailed study in iron

Although high electronic excitations were neglected for a long time in radiation effect studies of metallic targets, it is now well established that they can play a dominant role in the damaging processes of some metals. Iron is especially interesting in so far as, according to the rate of energy deposition in electronic excitations (d E/d x) e, various behaviours are observed. Below (d E/d x) e ≈ 40 keV/nm, due to electronic excitations, the amount of damage introduced in the sample is smaller than that expected from the sole elastic collisions. On the contrary, at very high (d E/d x) e levels, a strong enhancement of the damage occurs. After describing the experimental results obtained during low temperature irradiations with a few 10 MeV/nucleon heavy (oxygen to uranium) ions, a phenomenological model which accounts for this intricate behaviour will be presented. Finally, a microscopic mechanism will be proposed to explain how the energy given to the electronic system can play a role in damage processes involving atomic motion. Molecular dynamics simulations validate this approach.

The nature of the influence of speed on adult age differences in cognition.

Two studies were conducted to determine the relations among age, motor speed, perceptual speed, and 3 measures of cognitive performance: study time, decision time, and decision accuracy. Each study involved over 240 adults between I 8 and over 80 years of age who all performed a battery of tests, including computer-administered tests of memory, reasoning, and spatial ability. The results indicated that (a) increased age was associated with lower accuracy as well as with longer study time and decision time and (b) some ofthe relations between age and decision accuracy and between age and decision time appear to be mediated by a slower rate ofexecuting cognitive operations. Considerable evidence now exists indicating that a large proportion ofthe age-related variance in many different cognitive variables is shared with a measure of perceptual speed. Among the most pertinent results are the findings that the age-related diffbrences in various measures of cognitive functioning are greatly reduced when statistical control procedures are used to adjust for differences in perceptual speed. As an illustration of this phenomenon, Thble I in Salthouse (1993b) contains 44 comparisons across a wide range of cognitive variables. Age was associated with a mean of l6.2Vo of the total variance in the variables, but after the variance associated with measures of perceptual speed was held constant, age was associated with only 3.6Vo ofthe variance in the cognitive variables.

Effects of cyanoacrylate tissue adhesives on cartilage graft viability

Cartilage graft fixation using cyanoacrylate tissue adhesives has aided in the accuracy and stability of these grafts in facial reconstructive procedures. To objectively determine how these adhesives affect cartilage viability, freshly harvested cartilage from septoplasty procedures was bonded in vitro with one of four cyanoacrylate adhesives: Histoacryl, Bucrylate, Krazy Glue, or Eastman 910 monomer. Viable chondrocytes will incorporate the sulfur-35 (35S) isotope in the synthesis of chondroitin sulfate, and is therefore a reliable test of cartilage viability. The bonded cartilage specimens were stored from 3 days to 4 weeks at 4 degrees C and then were incubated with the 35S isotope. Autoradiographs were made and the sections were counterstained. Throughout the study period, there was no statistical difference in the viability of Histoacryl-bonded specimens as compared to the controls. Specimens bonded with Bucrylate, Krazy Glue, and Eastman 910 monomer statistically demonstrated markedly less viability compared to those bonded with Histoacryl at the P = .01 level of significance. Further, the cartilage separated from these latter adhesives at the longer study times, most likely secondary to cartilage devitalization. Histoacryl optimizes graft viability as compared to these other available cyanoacrylate tissue adhesives in vitro.

Memory performance and use of a compensation after traumatic brain injury

Abstract Fifty-seven traumatic brain injured (TBI) patients were compared to fifty-five age and education-matched normal controls on a memory paired associate task. The TBI patients showed worse memory performance and longer study times than controls. There was no difference between the groups in the frequency of using a pencil and paper compensation to perform the task. Controls who used a compensation tended to perform at a higher level, but this was not true for TBI patients. Failure to benefit immediately from a compensation may help explain why some TBI patients resist using them during neuropsychological rehabilitation.