ABSTRACT
Abstract Deionized ammonium (NH3) acute toxicity (LC50-96h) in Patagonian blenny juveniles (Eleginops maclovinus) was assessed. Concentrations of deionized ammonium in salt water were prepared by using 24.09 ± 2.1 g ammonium chloride (NH4Cl). Fish were exposed in triplicates to different ammonium concentrations: 0.05; 0.094; 0.175; 0.325 and 0.605 mg NH3 L-1. Additionally, a control group was included. Experimental fish were kept at a photoperiod of 16:8h. Average temperatures were 16.24 ± 1.40 °C. Oxygen concentration was 7.16 ± 0.40 mg L -1. Water pH was 7.89 ± 0.2. LC50-96 h, was estimated by using Probit statistical method (95% intervals) using EPA software (1993). Juveniles of E. maclovinus showed a LC50-96h of 0.413mg NH3 L-1 value, different from most marine species. This study presents the first record of ammonium toxicity in marine species of Chile.
Resumo A toxicidade aguda (LC50-96h) de amônia deionizada (NH3 ) em Babosas-da-Patagônia (Eleginops maclovinus) juvenis foi avaliada. As concentrações de sal de amônia deionizada em água foram preparados com 24,09 ± 2,1 g de cloreto de amônio (NH4Cl). Os peixes foram expostos em triplicata a diferentes concentrações de amônia: 0,05; 0,094; 0,175; 0,325 e 0,605 mg L-1 de NH3. Além disso, um grupo de controle foi incluído. Peixes experimentais foram mantidos em fotoperíodo de 16: 8h. As temperaturas médias foram 16,24 + 1,40 °C. A concentração de oxigênio foi 16.24 +1.40°C mg L-1 . O pH da água foi de 7,89 + 0,2. h LC50-96h, foi estimada usando o método estatístico de Probit (intervalos de 95%) usando o software EPA (1993). E. maclovinus juvenis apresentaram uma LC 50-96h de 0.413mg NH3 L-1 valor diferente da maioria das espécies marinhas. Este estudo apresenta o primeiro registro de toxicidade amónio em espécies marinhas do Chile.
Subject(s)
Animals , Perciformes/growth & development , Perciformes/physiology , Ammonium Compounds/toxicity , Fish Diseases/chemically induced , Temperature , Water Pollutants, Chemical/toxicity , ChileABSTRACT
Abstract The present study assessed the percentage of survival and metamorphosis of larval stages of Caligus rogercresseyi (Boxshall and Bravo, 2000) nauplius I, nauplius II to and nauplius II to copepodite, conducting bioassays in triplicate with 50 larvae each, nauplius I or nauplius II, at temperature of 12 °C, 15 °C and 18 °C; salinity 20, 23, 25, 2729, 31, 33 and 35 g/L and oxygen saturation with ranges between 30-60%, 90-100% and 190 - 200%. Bioassays were performed in station Quillaipe of Fundación Chile, Puerto Montt, Chile. It is concluded that the temperature is inversely proportional to the time of metamorphosis and survival of the larvae of Caligus rogercresseyi . In salinity is observed that increased this, greater is the percentage of survival and metamorphosis is faster, while the larvae do not survive less than 20g/L. Oxygen saturation ranges indicate that the larvae do not survive at saturations between 30-60%, and it had no differences between 90-100% saturation and 190-200%.
Resumo O presente estudo avaliou a percentagem de sobrevivência e metamorfose dos estádios larvais de Caligus rogercresseyi (Boxshall and Bravo, 2000) nauplio I, nauplio II ae nauplio II a copepodita, realizando bioensaios em triplicado com 50 larvas cada, nauplio I ou nauplio II, À temperatura de 12 °C, 15 °C e 18 °C; Salinidade 20, 23, 25, 2729, 31, 33 e 35 g / L e saturação de oxigénio com variações entre 30-60%, 90-100% e 190-200%. Os bioensaios foram realizados na estação Quillaipe da Fundação Chile, Puerto Montt, Chile. Conclui - se que a temperatura é inversamente proporcional ao tempo de metamorfose e sobrevivência das larvas de Caligus rogercresseyi. Na salinidade observa-se que aumentou esta, maior é a percentagem de sobrevivência e metamorfose é mais rápida, enquanto as larvas não sobrevivem menos de 20g / L. Os intervalos de saturação de oxigénio indicam que as larvas não sobrevivem a saturações entre 30-60% e não têm diferenças entre 90-100% de saturação e 190-200%.
Subject(s)
Animals , Copepoda/physiology , Larva/physiology , Metamorphosis, Biological/physiology , ChileABSTRACT
The present study assessed the percentage of survival and metamorphosis of larval stages of Caligus rogercresseyi (Boxshall and Bravo, 2000) nauplius I, nauplius II to and nauplius II to copepodite, conducting bioassays in triplicate with 50 larvae each, nauplius I or nauplius II, at temperature of 12 °C, 15 °C and 18 °C; salinity 20, 23, 25, 2729, 31, 33 and 35 g/L and oxygen saturation with ranges between 30-60%, 90-100% and 190 - 200%. Bioassays were performed in station Quillaipe of Fundación Chile, Puerto Montt, Chile. It is concluded that the temperature is inversely proportional to the time of metamorphosis and survival of the larvae of Caligus rogercresseyi . In salinity is observed that increased this, greater is the percentage of survival and metamorphosis is faster, while the larvae do not survive less than 20g/L. Oxygen saturation ranges indicate that the larvae do not survive at saturations between 30-60%, and it had no differences between 90-100% saturation and 190-200%.
Subject(s)
Copepoda/physiology , Larva/physiology , Metamorphosis, Biological/physiology , Animals , Chile , Oxygen/analysis , Salinity , Seawater/chemistry , TemperatureABSTRACT
Deionized ammonium (NH3) acute toxicity (LC50-96h) in Patagonian blenny juveniles (Eleginops maclovinus) was assessed. Concentrations of deionized ammonium in salt water were prepared by using 24.09 ± 2.1 g ammonium chloride (NH4Cl). Fish were exposed in triplicates to different ammonium concentrations: 0.05; 0.094; 0.175; 0.325 and 0.605 mg NH3 L-1. Additionally, a control group was included. Experimental fish were kept at a photoperiod of 16:8h. Average temperatures were 16.24 ± 1.40 °C. Oxygen concentration was 7.16 ± 0.40 mg L -1. Water pH was 7.89 ± 0.2. LC50-96 h, was estimated by using Probit statistical method (95% intervals) using EPA software (1993). Juveniles of E. maclovinus showed a LC50-96h of 0.413mg NH3 L-1 value, different from most marine species. This study presents the first record of ammonium toxicity in marine species of Chile.
Subject(s)
Ammonium Compounds/toxicity , Fish Diseases/chemically induced , Perciformes , Animals , Chile , Perciformes/growth & development , Perciformes/physiology , Temperature , Water Pollutants, Chemical/toxicityABSTRACT
Abstract The present study assessed the percentage of survival and metamorphosis of larval stages of Caligus rogercresseyi (Boxshall and Bravo, 2000) nauplius I, nauplius II to and nauplius II to copepodite, conducting bioassays in triplicate with 50 larvae each, nauplius I or nauplius II, at temperature of 12 °C, 15 °C and 18 °C; salinity 20, 23, 25, 2729, 31, 33 and 35 g/L and oxygen saturation with ranges between 30-60%, 90-100% and 190 - 200%. Bioassays were performed in station Quillaipe of Fundación Chile, Puerto Montt, Chile. It is concluded that the temperature is inversely proportional to the time of metamorphosis and survival of the larvae of Caligus rogercresseyi . In salinity is observed that increased this, greater is the percentage of survival and metamorphosis is faster, while the larvae do not survive less than 20g/L. Oxygen saturation ranges indicate that the larvae do not survive at saturations between 30-60%, and it had no differences between 90-100% saturation and 190-200%.
Resumo O presente estudo avaliou a percentagem de sobrevivência e metamorfose dos estádios larvais de Caligus rogercresseyi (Boxshall and Bravo, 2000) nauplio I, nauplio II ae nauplio II a copepodita, realizando bioensaios em triplicado com 50 larvas cada, nauplio I ou nauplio II, À temperatura de 12 °C, 15 °C e 18 °C; Salinidade 20, 23, 25, 2729, 31, 33 e 35 g / L e saturação de oxigénio com variações entre 30-60%, 90-100% e 190-200%. Os bioensaios foram realizados na estação Quillaipe da Fundação Chile, Puerto Montt, Chile. Conclui - se que a temperatura é inversamente proporcional ao tempo de metamorfose e sobrevivência das larvas de Caligus rogercresseyi. Na salinidade observa-se que aumentou esta, maior é a percentagem de sobrevivência e metamorfose é mais rápida, enquanto as larvas não sobrevivem menos de 20g / L. Os intervalos de saturação de oxigénio indicam que as larvas não sobrevivem a saturações entre 30-60% e não têm diferenças entre 90-100% de saturação e 190-200%.
ABSTRACT
Abstract Deionized ammonium (NH3) acute toxicity (LC50-96h) in Patagonian blenny juveniles (Eleginops maclovinus) was assessed. Concentrations of deionized ammonium in salt water were prepared by using 24.09 ± 2.1 g ammonium chloride (NH4Cl). Fish were exposed in triplicates to different ammonium concentrations: 0.05; 0.094; 0.175; 0.325 and 0.605 mg NH3 L-1. Additionally, a control group was included. Experimental fish were kept at a photoperiod of 16:8h. Average temperatures were 16.24 ± 1.40 °C. Oxygen concentration was 7.16 ± 0.40 mg L -1. Water pH was 7.89 ± 0.2. LC50-96 h, was estimated by using Probit statistical method (95% intervals) using EPA software (1993). Juveniles of E. maclovinus showed a LC50-96h of 0.413mg NH3 L-1 value, different from most marine species. This study presents the first record of ammonium toxicity in marine species of Chile.
Resumo A toxicidade aguda (LC50-96h) de amônia deionizada (NH3 ) em Babosas-da-Patagônia (Eleginops maclovinus) juvenis foi avaliada. As concentrações de sal de amônia deionizada em água foram preparados com 24,09 ± 2,1 g de cloreto de amônio (NH4Cl). Os peixes foram expostos em triplicata a diferentes concentrações de amônia: 0,05; 0,094; 0,175; 0,325 e 0,605 mg L-1 de NH3. Além disso, um grupo de controle foi incluído. Peixes experimentais foram mantidos em fotoperíodo de 16: 8h. As temperaturas médias foram 16,24 + 1,40 °C. A concentração de oxigênio foi 16.24 +1.40°C mg L-1 . O pH da água foi de 7,89 + 0,2. h LC50-96h, foi estimada usando o método estatístico de Probit (intervalos de 95%) usando o software EPA (1993). E. maclovinus juvenis apresentaram uma LC 50-96h de 0.413mg NH3 L-1 valor diferente da maioria das espécies marinhas. Este estudo apresenta o primeiro registro de toxicidade amónio em espécies marinhas do Chile.
ABSTRACT
During spinal cord development, commissural (C) neurons, located near the dorsal midline, send axons ventrally and across the floor plate (FP). The trajectory of these axons toward the FP is guided in part by netrins. The mechanisms that guide the early phase of C axon extension, however, have not been resolved. We show that the roof plate (RP) expresses a diffusible activity that repels C axons and orients their growth within the dorsal spinal cord. Bone morphogenetic proteins (BMPs) appear to act as RP-derived chemorepellents that guide the early trajectory of the axons of C neurons in the developing spinal cord: BMP7 mimics the RP repellent activity for C axons in vitro, can act directly to collapse C growth cones, and appears to serve an essential function in RP repulsion of C axons.
Subject(s)
Bone Morphogenetic Proteins/physiology , Neurons/physiology , Spinal Cord/cytology , Spinal Cord/embryology , Transforming Growth Factor beta , Animals , Axons/physiology , Bone Morphogenetic Protein 7 , Bone Morphogenetic Proteins/antagonists & inhibitors , Bone Morphogenetic Proteins/genetics , COS Cells , Culture Techniques , Follistatin , Gene Expression , Glycoproteins/pharmacology , Immunoglobulin G/pharmacology , Mice , Nerve Growth Factors/pharmacology , Netrin-1 , Neurites/physiology , Rats , Spinal Cord/metabolism , Time Factors , Transfection , Tumor Suppressor ProteinsABSTRACT
Job-related vision standards benefit both employee and employer. By comparing employees' vision to specific job requirements, workers can be better placed into positions commensurate with their visual abilities. For a company without a vision care program, a project was undertaken to determine visual standards, and the need for vision care services for employees to better meet these standards. The critical factors for performing specific visual tasks for 40 job classifications were identified through direct observation and measurement, and through worker interviews. Additionally, a sample of employees was screened to determine plant population characteristics, and to determine what percentage of employees met the newly formed standards. This study can serve as a model for the application of visual standards to the workplace and is pertinent, as "reduced vision" is increasingly defined by government as a disability.
Subject(s)
Occupational Health , Personnel Selection , Task Performance and Analysis , Vision Screening , Adult , Color Perception , Female , Humans , Male , Middle Aged , Reference Standards , Vision, Binocular , Visual Acuity , Visual FieldsSubject(s)
Optometry/trends , Schools, Health Occupations/trends , Alabama , Humans , Optometry/educationABSTRACT
The differentiation of distinct cell types in the ventral neural tube depends on local inductive signals from the notochord. We have isolated a vertebrate homolog of the Drosophila segment polarity gene hedgehog (hh) from zebrafish and rat, termed vhh-1. vhh-1 is expressed in the node, notochord, floor plate, and posterior limb bud mesenchyme. Each of these cell groups has floor plate inducing activity, suggesting that the vhh-1 gene may encode a floor plate-inducing molecule. Widespread expression of rat vhh-1 in frog embryos leads to ectopic floor plate differentiation in the neural tube. In vitro tests for the signaling functions of vhh-1 demonstrate that COS cells expressing the rat vhh-1 gene induce floor plate and motor neuron differentiation in neural plate explants. vhh-1 may, therefore, contribute to the floor plate and motor neuron inducing activities of the notochord.
Subject(s)
Drosophila Proteins , Embryonic Induction , Nervous System/embryology , Proteins/genetics , Trans-Activators , Amino Acid Sequence , Animals , Base Sequence , Cell Differentiation , Chick Embryo , DNA Primers/chemistry , Extremities/embryology , Gene Expression , Hedgehog Proteins , In Situ Hybridization , Molecular Sequence Data , Motor Neurons/cytology , Proteins/chemistry , RNA, Messenger/genetics , Rats , Sequence Alignment , Sequence Homology, Amino Acid , Solubility , Xenopus laevis , Zebrafish/genetics , Zebrafish ProteinsABSTRACT
To determine the contribution made by optometrists in blood pressure measurement and comanagement, a short survey was sent to all the optometrists licensed in Ohio. Of those responding, over 90% reported to routinely question their patients concerning blood pressure, while 72% reported to have blood pressure measuring equipment in their offices. Optometrists can continue to be strong members of the primary health care team by adhering to the recommendations delineated in the 1988 Report of the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure. Practitioners should measure blood pressure at each patient visit, provide feedback to the patient concerning the findings, and follow the recommended follow-up criteria.
Subject(s)
Hypertension/diagnosis , Optometry , Blood Pressure Determination , Delivery of Health Care , Follow-Up Studies , Humans , Surveys and QuestionnairesABSTRACT
Alcohol is a central nervous system depressant that can affect eye movement control. Even at low blood alcohol concentrations (BAC's) smooth pursuit eye tracking can be lost and horizontal nystagmoid movements become apparent at relatively small angles of lateral gaze. Law enforcement officers across the nation are being taught evaluation techniques to use these eye movement signs as an indicator of alcohol intoxication. Information obtained at the Ohio State Highway Patrol (OSHP) course on the Advanced Detection, Apprehension, and Prosecution of subjects suspected of driving a vehicle while intoxicated is presented here including the testing and scoring techniques of the horizontal gaze nystagmus sobriety test.
Subject(s)
Accidents, Traffic/prevention & control , Alcoholic Intoxication/physiopathology , Automobile Driving , Nystagmus, Physiologic , Evaluation Studies as Topic , Humans , Methods , Nystagmus, Physiologic/drug effects , Psychomotor Performance/drug effectsABSTRACT
As primary health care providers, optometrists can make a significant contribution to the overall health of our patients by routinely measuring blood pressure, referring those individuals with elevated blood pressures for evaluation and/or treatment, and supporting previously diagnosed hypertensives to maintain their treatment regimen. The 1984 Report of the Joint National Committee on Detection, Evaluation and Treatment of High Blood Pressure gives optometrists an up-to-date synopsis of blood pressure management. It includes referral procedures, blood pressure classifications, the revised stepped-care treatment approach and patient-professional interaction suggestions for improving long-term treatment compliance. It is imperative that optometrists reinforce the importance of regular hypertension evaluation to our patients and answer questions concerning blood pressure and its related follow-up care.
Subject(s)
Hypertension/diagnosis , Optometry/methods , Antihypertensive Agents/therapeutic use , Blood Pressure , Body Weight , Humans , Hypertension/physiopathology , Hypertension/therapy , Physician-Patient RelationsABSTRACT
Intraocular pressure measurements were made on 30 normal eyes using seven noncontact tonometers. The instruments were from 4 to 8 years old. Results show that pressures indicated by most noncontact tonometers are not significantly different. In the most extreme case, differences in mean pressures of 3.48 mm Hg were obtained. A difference of this magnitude may be important when following a patient over a period of time, and could be the result of measurements being made on a different tonometer.
Subject(s)
Intraocular Pressure , Tonometry, Ocular/instrumentation , Humans , Tonometry, Ocular/methodsABSTRACT
Clinical use of an innovative fundus camera system which takes extra wide-angle pictures is described. Advantages and limitations of the system are reviewed. Photographic patient examples are demonstrated.
Subject(s)
Fluorescein Angiography/methods , Fundus Oculi , Retinal Diseases/diagnosis , Humans , Retinal VesselsABSTRACT
A description of a clinic patient record review process completed during a recent ten week period at our teaching clinic is presented. The review was done by peer groups of clinicians including both students and clinical faculty. Consistent improvement in the percentage of records judged appropriate occurred during the ten week period. Educational as well as quality control advantages of this process are cited.
Subject(s)
Clinical Competence , Optometry/education , Peer Review , Humans , Records , Teaching/methodsABSTRACT
The luminance of the background and of the target (visual acuity letter) was measured for five commonly used visual acuity screen materials. Most materials were found to be highly nonlambertian. A greater than threefold difference in reflectance normal to the surface was found for the respective screens tested. The percent polarization maintained by each screen material, using American Optical Vectograph systems, was measured. The relative illuminations generated by eight projector systems were compared. A discussion of the factors and recommendations for improvements related to projected chart visibility are made.
Subject(s)
Light , Optometry/instrumentation , Visual Acuity , Field Dependence-Independence , Humans , Refraction, OcularABSTRACT
Ophthalmic materials from 11,677 spectacle-prescription orders were evaluated during an 18-mo period in a university optometry clinic. Five percent of the orders received were not acceptable based on criteria stemming from the ANSI-Z80. 1-1972 standards. Almost two-thirds of these rejections were lens related. Frame-related rejections were predominantly due to gross human error. Rejection rate and delivery time varied widely among the supplying laboratories. Rejection rate did not decrease with increased delivery time. Since notifying the laboratories of our results, the percentage of unacceptable orders has decreased.
Subject(s)
Eyeglasses/standards , Evaluation Studies as Topic , Humans , Quality ControlABSTRACT
Four clinical techniques for estimating cup/disc ratio were compared. Small differences in magnitude of the cup/disc ratio were found with each technique studied. In addition, a mean cup/disc ratio of between 0.22 and 0.30 was found for the subjects studied. The clinical utility of four funduscopic examination methods is reviewed.
