Artificial mouth opening fosters anoxic conditions that kill small estuarine fish

2009 ◽  
Vol 82 (4) ◽  
pp. 566-572 ◽  
Author(s):  
Alistair Becker ◽  
Laurie J.B. Laurenson ◽  
Kylie Bishop
Keyword(s):  
Mouth Opening ◽  
Estuarine Fish ◽  
Anoxic Conditions ◽  
Artificial Mouth

scholarly journals Fish communities of the Wilderness Lakes System in the southern Cape, South Africa

Koedoe ◽  
2016 ◽  
Vol 58 (1) ◽  
Author(s):  
Alexis A. Olds ◽  
Nicola C. James ◽  
M. Kyle S. Smith ◽  
Olaf L.F. Weyl
Keyword(s):  
South Africa ◽  
Key Management ◽  
Mouth Opening ◽  
Marine Species ◽  
Freshwater Species ◽  
Sediment Removal ◽  
Management Actions ◽  
System A ◽  
Artificial Mouth ◽  
Estuarine Resident

The Wilderness Lakes System, a temporarily open and closed estuary with three associated lakes situated in the southern Cape region of South Africa, was sampled using a range of sampling gears to assess the fish community. A total of 25 species were sampled throughout the system, with the highest diversity in the Touw Estuary (23 species) and the lowest in Langvlei (11 species). Estuary-associated marine species (13 species) dominated species richness with smaller proportions of estuarine resident (7 species), freshwater (3 species) and catadromous species (2 species). Estuarine resident species dominated the catch numerically. The size–class distribution of euryhaline marine species indicated that upon entering the Touw Estuary as juveniles, the fish move up the system towards Rondevlei where they appear to remain. Three freshwater species were recorded in the system, all of which are alien to the Wilderness Lakes System. Decreasing salinity in the upper lakes appears to be a driving factor in the distribution and increasing abundance of the freshwater fishes. Sampling followed a drought, with the system experiencing substantially increased levels of mouth closure compared to a similar study conducted in the 1980s. The timing of mouth opening and the degree of connectivity between the lakes influence the nursery function of the system as a whole. Management actions need to focus on improving ecological functioning of this system, in particular how mouth opening is managed, to facilitate nursery function and limit the establishment of invasive species.Conservation implications: Key management actions are required to improve fish recruitment potential into and within the system. These include maintenance of adequate marine inflow through adherence to artificial mouth breaching protocols and improving connectivity between the lakes through sediment removal from localised deposition points within the connecting channels.

Maximum Mouth Opening among Saudi Arabian Adults

2020 ◽  
Vol 4 (7) ◽  
pp. 46-51
Author(s):  
Fahad Alshammari ◽  
Njoud AlSaheel ◽  
Najd Alhamzah ◽  
Ra’ed Salma ◽  
Ahmed Alshammari
Keyword(s):  
Mouth Opening ◽  
Saudi Arabian

Robust Control of an Artificial Mouth for a Wind Musical Instrument

2018 ◽  
Author(s):  
Gaby Abou Haidar ◽  
Xavier Moreau ◽  
Roy Abi Zeid Daou
Keyword(s):  
Robust Control ◽  
Musical Instrument ◽  
Artificial Mouth

Abiotic reduction of 2,4-dinitrotoluene in the presence of sulfide minerals under anoxic conditions

1996 ◽  
Vol 34 (10) ◽  
pp. 25-33 ◽  
Author(s):  
Cheng Jiayang ◽  
Makram T. Suidan ◽  
Albert D. Venosa
Keyword(s):  
Electron Donor ◽  
Chemical Reduction ◽  
Sulfide Minerals ◽  
Sulfide Concentration ◽  
Magnesium Ions ◽  
High Concentration ◽  
Anoxic Conditions ◽  
High Affinity ◽  
Iron Nickel ◽  
Abiotic Reduction

Abiotic reduction of 2,4-dinitrotoluene (DNT) in the presence of sulfide minerals has been investigated under anoxic conditions at 35°C. 2,4-DNT was abiotically reduced to 4-amino-2-nitrotoluene (4-A-2-NT) and 2-amino-4-nitrotoluene (2-A-4-NT) in the presence of high concentration of sulfide (0.84 mM). No abiotic reduction of 2,4-DNT was observed in the presence of low sulfide concentration (0.42 mM). The rate and the extent of the abiotic reduction of 2,4-DNT were increased with an increase in sulfide concentration. Sulfide served as an electron donor for the reduction of 2,4-DNT. The 2-nitro group was preferentially reduced, making the 2-A-4-NT:4-A-2-NT ratio in the final products 2:1. The addition of iron, nickel, and cobalt minerals significantly enhanced the abiotic reduction. The FeS, NiS, and CoS solids formed in the serum bottles catalyzed the reduction of 2,4-DNT preferentially to 4-A-2-NT. MnS and CuS solids also catalyzed the reduction of 2,4-DNT to 4-A-2-NT, but did not change the overall reduction of 2,4-DNT. However, the presence of calcium, zinc, and magnesium minerals impeded 2,4-DNT reduction. The calcium, zinc, and magnesium ions have a high affinity to sulfide, inactivating sulfide as an electron donor for the chemical reduction of 2,4-DNT.

The effect of heterotrophic yield on the assessment of the correction factor for anoxic growth

1996 ◽  
Vol 34 (5-6) ◽  
pp. 67-74 ◽  
Author(s):  
D. Orhon ◽  
S. Sözen ◽  
N. Artan
Keyword(s):  
Correction Factor ◽  
Domestic Sewage ◽  
Yield Coefficient ◽  
Heterotrophic Growth ◽  
Metabolic Processes ◽  
Anoxic Conditions ◽  
Industrial Wastewaters ◽  
Systems Modelling ◽  
Kinetics Of ◽  
Very High

For single-sludge denitrification systems, modelling of anoxic reactors currently uses the kinetics of aerobic heterotrophic growth together with a correction factor for anoxic conditions. This coefficient is computed on the basis of respirometric measurements with the assumption that the heterotrophic yield remains the same under aerobic and anoxic coditions. The paper provides the conceptual proof that the yield coefficient is significantly lower for the anoxic growth on the basis of the energetics of the related metabolic processes. This is used for the interpretation of the very high values for the correction factor experimentally determined for a number of industrial wastewaters. A default value for the anoxic heterotrophic yield coefficient is calculated for domestic sewage and compatible wastewaters and proposed for similar evaluations.

(Preprint)

2018 ◽  
Author(s):  
Dr Malathi Dayalan ◽  
Dr Sudeshna Sharma ◽  
Dr Shweta Poovani ◽  
Dr Saher Altaf
Keyword(s):  
Myofascial Pain ◽  
Mouth Opening ◽  
Masticatory Muscles ◽  
Matched Pair ◽  
Masticatory Muscle ◽  
Muscle Disorders ◽  
Occlusal Contact ◽  
Group I ◽  
Group Ii

BACKGROUND Masticatory system is a complex functional unit, primarily engaged in chewing, swallowing and breathing functions, and some parts are involved in taste recognition and determination of food consistency. Sophisticated functional performances of speech and emotional expressions are specifically human qualities. Irregularities in occlusion appears to be the precipitating factor in the pathogenesis of myofascial pain dysfunction syndrome. Tek- Scan III records the bite length, number, distribution, timing, duration and the relative force of each tooth contact. It also records the sequence of occlusal contacts in terms of time and the associated force with each occlusal contact. The aim of this study was to treat masticatory muscle disorders with occlusal equilibration, and compare the efficacy of treatment outcomes between selective grinding and stabilization splints using Tek-Scan III. OBJECTIVE Objective of this study was to compare the efficacy of occlusal equilibration achieved through selective griding and stabilization splints using Tek-Scan III. METHODS In this in vivo study, 40 patients with masticatory muscle disorders were selected based on the inclusion and exclusion criteria. The occlusal discrepancies were analyzed using Tek-Scan III. The selected 40 subjects were then randomly divided into 2 groups based on the treatment they recieved; Group I – Selective grinding group (20) and Group II – Stabilization splint group (20). Comparison of pre-treatment and post treatment results were evaluated in terms of pain, mouth opening, left and right side force percentage as recorded through Tek-Scan III and reduction of disclusion time. Statistical analysis was carried out with Kolmogorov Smirnov test, Wilcoxon matched pair test and Mann-Whitney U test. RESULTS Wilcoxon matched pairs test demonstrated that there was statistically significant results ( p = 0.0007) in both the groups for reduction of disclusion time, elimination of pain and improved mouth opening. Patients in Group I showed better results as compared to Group II in terms of disclusion time, pain and mouth opening. CONCLUSIONS Occlusal equilibration brought about by reducing the disclusion time using the Tek- Scan III reduced the symptoms of pain in masticatory muscles. Patients in group I (Selective grinding) however showed better results when compared to patients in group II (Stabilization splints).

scholarly journals Comparative Study of Intralesional Dexamethasone Plus Hyaluronidase & Oral Colchicine in Patients with Oral Submucous Fibrosis

2018 ◽  
Vol 14 (2) ◽  
pp. 60-65
Author(s):  
Ganesh Prasad Neupane ◽  
Maya Rai ◽  
R. S. Rathore ◽  
V. K. Bhargava ◽  
A. K. Mahat ◽  
...  
Keyword(s):  
Treatment Outcomes ◽  
Oral Mucosa ◽  
Oral Submucous Fibrosis ◽  
Mouth Opening ◽  
Study Groups ◽  
T Test ◽  
Significant Difference ◽  
Intralesional Injections ◽  
Submucous Fibrosis ◽  
Larger Sample

Introduction: Oral Submucous Fibrosis (OSMF) is a precancerous condition of the oral mucosa. It is characterized by excessive production of collagen leading to inelasticity of the oral mucosa and atrophic changes of the epithelium.Aim and objective: To evaluate the efficacy of oral Colchicine in comparison to intralesional injections of Dexamethasone plus Hyaluronidase in the management of OSMF patients.Materials and Methods: Fourty patients with OSMF were randomly divided equally into two groups. 20 patients in Dexamethasone group received biweekly intralesional injections of Dexamethasone (4mg/ml) plus Hyaluronidase 1500 IU in buccal mucosa for a period of 12 weeks. Other 20 patients in Colchicine group received oral Colchicine 0.5 mg tablets twice daily for 12 weeks. Parameters taken in the study were burning sensation, and mouth opening. Descriptive statistics, paired t test and unpaired t test were used for statistical analysis.Results and Conclusions: The pre- and post-treatment differences were found to be statistically significant for both the groups (p<0.001) and for both the treatment outcomes. When the average difference of the treatment outcomes was compared between the two study groups, statistically highly significant difference was noted (p <0.001) only in mouth opening but not in burning sensation.These encouraging results should prompt further clinical trials with Colchicine on a larger sample size to broaden the therapeutic usefulness of the drug in the management of OSMF. JNGMC,  Vol. 14 No. 2 December 2016, Page: 60-65

scholarly journals To Establish A Normal Range of Inter-Incisal Opening - A Study of 756 Subjects of Age Group 20-50 Years in Yamunanagar City, Haryana.

2013 ◽  
Vol 01 (01) ◽  
pp. 001-003
Author(s):  
Aruna Singh ◽  
Nymphea Pandit ◽  
Monica Sharma
Keyword(s):  
Pearson Correlation ◽  
Mouth Opening ◽  
Clinical History ◽  
P Value ◽  
Age Group ◽  
Male Population ◽  
Female Population ◽  
Odontogenic Infections ◽  
Anterior Teeth ◽  
Average Maximum

Abstract Aim- 1. The aim of this study was to investigate the average maximum range of inter-incisal mouth opening in a representative sample of the adult subjects of Haryana. 2. To see any correlation between maximal inter-incisal opening with age. Methods- Maximum mouth opening was studied in 756 adult subjects with age range of 20-50 years in Yamunanagar, Haryana. Age limit was further divided into three groups (20-30, 31-40, 41-50). Those with clinical history of TMJ involvement, OSMF, any trauma, odontogenic and non-odontogenic infections, dental prosthesis on the anterior teeth, congenital anomalies in the maxillofacial region were excluded from this study. The measurements were recorded twice and mean of the two values were taken. Statistical Analysis- Independent sample t-test was calculated to compare age and mouth opening in both male and females respectively. Bivariate pearson correlation was used to see any relationship between age and mouth opening. P-value ≤ 0.05 and CI (confidence interval) at 95% were considered statistically significant. The Results- The average mouth opening of males (45.36±6.70 mm) subjects was higher as compared to female (41.27 ± 6.75 mm) with significant, p-value 0.000. The mean mouth opening ± SD for both sexes combined was 43.39 ± 7.02 mm. The corresponding values for mean inter-incisal opening in male population aged 20-30, 31-40, 41-50 were 45.52 ± 7.15, 46.16 ± 5.47, 42.96 ± 6.82 mm and in female population aged 20-30, 31-40, 41-50 were 41.40 ± 7.08, 41.60 ± 6.29 and 40.03 ± 6.38 mm respectively. Conclusion- Maximal mouth opening differ significantly with gender. There is a decrease in MMO with older age group.

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