181 research outputs found
Perceptualand cognitive factors imposing "speed limits" on reading rate: a study with the rapid serial visual presentation
Adults read at high speed, but estimates of their reading rate vary greatly, i.e., from 100 to 1500 words per minute (wpm). This discrepancy is likely due to different recording methods and to the different perceptual and cognitive processes involved in specific test conditions. The present study investigated the origins of these notable differences in RSVP reading rate (RR). In six experiments we investigated the role of many different perceptual and cognitive variables. The presence of a mask caused a steep decline in reading rate, with an estimated masking cost of about 200 wpm. When the decoding process was isolated, RR approached values of 1200 wpm. When the number of stimuli exceeded the short-term memory span, RR decreased to 800 wpm. The semantic context contributed to reading speed only by a factor of 1.4. Finally, eye movements imposed an upper limit on RR (around 300 wpm). Overall, data indicate a speed limit of 300 wpm, which corresponds to the time needed for eye movement execution, i.e., the most time consuming mechanism. Results reconcile differences in reading rates reported by different laboratories and thus provide suggestions for targeting different components of reading rate
Fungi and arsenic. Tolerance and bioaccumulation by soil saprotrophic species
Increasing arsenic environmental concentrations are raising worldwide concern for its impacts on human health and ecosystem functionality. In order to cope with arsenic contamination, bioremediation using fungi can represent an efficient, sustainable, and cost-effective technological solution. Fungi can mitigate arsenic contamination through different mechanisms including bioaccumulation. In this work, four soil saprotrophic fungi Absidia spinosa, Purpureocillium lilacinum, Metarhizium marquandii, and Cephalotrichum nanum, isolated from soils with naturally high arsenic concentrations, were tested for their ability to tolerate different sodium arsenite concentrations and accumulate As in different cultural conditions. pH medium after fungal growth was measured to study pH variation and metabolic responses. Arsenic bioaccumulation and its influence on the uptake of other elements were investigated through multi-elemental analysis using hydride generation atomic fluorescence spectrometry (HG-AFS), inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectroscopy (ICP-OES). Considering the increasing interest in siderophore application for metal bioremediation, the production of siderophores and their affinity for both Fe and As were also evaluated. All species were able to tolerate and accumulate As in their biomass in all of the tested conditions and produced siderophores with different affinities for Fe and As. The results suggest that the tested fungi are attractive potential candidates for the bioremediation of As contaminated soil and worthy of further investigation
Physiopathology of Bone Modifications in β-Thalassemia
β-thalassemia major (βTM) or Cooley anemia is characterized by significantly reduced or absent synthesis of β-globin chains, which induces important pathologic consequences including hemolytic anemia, altered erythropoiesis, and bone marrow overstimulation. The pathogenesis of bone changes in patients with βTM is not yet completely understood. However, an unbalance in bone mineral turnover resulting from increased resorption and suppression of osteoblast activity has been detected in βTM patients. The abnormal regulation of bone metabolism may be related to hormonal and genetic factors, iron overload and iron chelation therapy, nutritional deficits, and decreased levels of physical activity. Here, we review the most recent findings on the physiopathology of bone abnormalities in βTM. Clinical presentation and radiological features of βTM-related bone changes are also discussed
Physiopathology of Spine Metastasis
The metastasis is the spread of cancer from one part of the body to another. Two-thirds of patients with cancer will develop bone metastasis. Breast, prostate and lung cancer are responsible for more than 80% of cases of metastatic bone disease. The spine is the most common site of bone metastasis. A spinal metastasis may cause pain, instability and neurological injuries. The diffusion through Batson venous system is the principal process of spinal metastasis, but the dissemination is possible also through arterial and lymphatic system or by contiguity. Once cancer cells have invaded the bone, they produce growth factors that stimulate osteoblastic or osteolytic activity resulting in bone remodeling with release of other growth factors that lead to a vicious cycle of bone destruction and growth of local tumour
Infection following bone tumor resection and reconstruction with tumoral prostheses: a literature review.
Bone resection is the choice treatment of malignant bone tumors. Tumor prosthesis is one of the most common solutions of reconstruction following resection of bone tumor located to the metaphysis of long bones. Periprosthetic infections are a frequent complication of limb-salvage surgery which is largely due to prolonged and repeated surgeries, as well as to the immunocompromised condition of these patients due to neoplastic treatment. Furthermore, the large exposure of tissues during this type of surgery and the dissection across vascular distributions also contributes to the high risk of infection. The authors reviewed the literature discussing the incidence of infections of tumor prosthesis implanted following resection of bone tumors, taking into account the different sites of implantation. In the English literature, the highest risk of infection which led to limb amputation was observed after proximal tibia resection and this difference was considered to be due to the poor condition of soft tissue and also after pelvic resection due to huge dead space after sarcoma resection not filled by implant. Independent of the location, the management of infected prosthesis is similar. That is, after one or more attempts at debridement and antibiotic therapy, it consists of implant removal and insertion of a new implant in a one- or two-stage procedure, with a decreased risk of failure with the two-stage procedure
Local adjuvants in surgical management of bone metastases.
Curettage is one of the most common method for surgical treatment of bone metastasis. Local adjuvant improve most commonly used for improving the effect of curettage in local cancer surgery may exerted their effects either chemically either physically; in Orthopedic Oncology the most common are phenol, liquid nitrogen, laser, and cement. This article reviewed the main characteristics of the most common chemical and physical agents used in bone oncology, emphasizing the toxic effects of some of them, especially phenol and liquid nitrogen
USING BLACK SOLDIER FLIES (HERMETIA ILLUCENS) TO BIOCONVERT WASTE FROM THE LIVESTOCK PRODUCTION CHAIN: A LIFE CYCLE ASSESSMENT CASE STUDY
The aim of this study was to enhance waste from the livestock production chain using insects to produce
biomaterials that can fall within the agricultural production cycle (e.g. plastic mulch), in order to
achieve sustainability throughout the technological process. After stabilization by drying, mature larvae
of Hermetia illucens reared on substrate composed of poultry manure, zeolite and water were
chemically separated in the laboratory to extract the proteic, lipidic and chitinic fractions. Proteins were
then isolated and added to other components in order to obtain bioplastics. The environmental impacts
of the bioplastic production process developed at a laboratory scale was evaluated through the LCA
methodology
THE MANAGEMENT OF POSTOPERATIVE PAIN AFTER HEMORRHOIDECTOMY: ANALYSIS OF THREE METHODICS
Postoperative pain is one of the most common and disabling complications following hemorrhoidectomy. This study divided a
total of 90 patients, undergone Milligan and Morgan hemorrhoidectomy, in three groups of 30 patient: Group A, undergone internal
sphincterotomy after hemorrhoidectomy; Group B, treated with Diosmin 500 mg; Group C, treated with Paracetamol 1000 mg when
required. The analysis of the median VAS score (Visual Analogic Scale) of postoperative pain, in every group pointed out a relationship
between postoperative pain reduction and time at the three set checkpoints (1st, 3rd, 9th postoperative day) (R2= 0.9231 for
Group A; R2= 0.9423 for group B; R2= 0.9423 for group C). Mean VAS scores have been worked out for the three checkpoints and
we compared the results between the three groups.
Conclusions: in our study, internal sphincterotomy was the only therapeutic choice able to reduce most of the others the postoperative
pain, both the 1st, the 3rd and the 9th postoperative day
Comparison between Rapid Intraoperative and Central Laboratory Parathormone Dosage in 12 Kidney Transplant Candidates
Background The rapid intraoperative parathormone (PTH) and at central laboratory PTH dosage gives similar results. The central laboratory provides results in longer times and higher costs. Intraoperative measurement can reduce time and costs during parathyroidectomy. Methods Twelve patients undergoing parathyroidectomy for hyperparathyroidism renal transplant candidates were included. Diagnosis was made by laboratory tests (serum calcium, PTH) and imaging techniques (ultrasonography and scintigraphy). All patients presented PTH levels of >400 pg/mL (the limit value to be maintained in list for kidney transplantation) and resistant to medical therapy. For each patient, 2 blood samples were collected before surgery at anesthesia induction for PTH testing intraoperative (rapid assay) and central laboratory, and 10 minutes after the removal of each gland. The times from collection-processing to communication to the surgeon of the results were compared for both the methods. It was considered successful the abatement of PTH of ≥70% at rapid intraoperative testing and consequently surgical intervention stopped before communication of central laboratory PTH testing. Results The average time of reporting the test results of the central laboratory was 41.5 minutes (SD ± 9), whereas with the rapid intraoperative PTH (ioPTH) testing the average time was 9.9 minutes (SD ± 2.02). An average of 33.6 minutes of the duration per intervention (SD ± 10.27) were virtually saved with the use of ioPTH testing. The 2 values of the Pearson correlation (ρ) of 0.99 obtained (for baseline) and 0.975 (for the 10-minute) lead us to conclude that there is an excellent correlation between the series of data. Conclusions Rapid ioPTH testing, owing to its accuracy, permits a dramatic reduction of operating time for patients with secondary hyperparathyroidism that need to be treated before inclusion on the waiting list
Aquatic insects from Somuncura plateau, Patagonia, Argentina. Preliminary inventory
Se brinda un inventario preliminar de los insectos acuáticos de la Meseta del Somuncura y su área de influencia (Patagonia, Argentina) realizado sobre la base de colecciones y registros previos de especies pertenecientes a los órdenes Ephemeroptera, Odonata, Hemiptera (Heteroptera), Trichoptera, Diptera (familias Ceratopogonidae, Culicidae y Psychodidae) y Coleoptera. Se han relevado diversos tipos de ambientes en 14 localidades. El número de especies registrado asciende a 78, agrupadas en 51 géneros y 26 familias, de las cuales 33 se citan por primera vez del área. De los taxa registrados 83% de los géneros corresponden a grupos de amplia distribución (neotropicales, americanos o cosmopolitas), mientras que 41% de las especies presentan una distribución patagónica o andina.A preliminary inventory of the aquatic insects from the Somuncura plateau and its area of influence (Patagonia, Argentina) is presented. It was done on the basis of the study of collections and previous records of species belonging to the orders Ephemeroptera, Odonata, Hemiptera (Heteroptera), Trichoptera, Diptera (families Ceratopogonidae, Culicidae, and Psychodidae) and Coleoptera. Different kinds of environments were surveyed in 14 localities. Seventy eigth species grouped in 51 genera and 26 families were registered, and 33 species are new records for the area. Eighty three % of the registered genera are widely distributed (neotropical, american or cosmopolitan), while 41 % of the species exhibit patagonic or andean distribution.Fil: Muzon, Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología ; ArgentinaFil: Spinelli, Gustavo Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología ; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; ArgentinaFil: Pessacq, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología ; ArgentinaFil: Von Ellenrieder, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología ; ArgentinaFil: Estevez, Ana Lia. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; ArgentinaFil: Marino, Pablo Ignacio. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Pérez Goodwyn, Pablo J.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología ; ArgentinaFil: Angrisano, Elisa Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Diaz, Maria Florentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fernandez, Liliana Alicia. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mazzucconi, Silvia Ana. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; ArgentinaFil: Rossi, Gustavo Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Salomón, Oscar Daniel. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Centro Nacional de Diagnóstico e Investigaciones Endemo-epidémicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
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