scholarly journals Population Ecology Studies on Infaunal Polychaetes of Pauatahanui Inlet

2021 ◽  
Author(s):  
◽  
Geoffrey Bernard Read
Keyword(s):  
Size Structure ◽  
Environmental Gradients ◽  
Age Groups ◽  
Differential Mortality ◽  
Intertidal Flat ◽  
Adult Size ◽  
Spawning Period ◽  
Near Surface ◽  
Pair Density ◽  
The Common

<p>Macrofaunal polychaete densities across a stable, fine-sand, intertidal flat in Pauatahanui Inlet were examined from a set of seasonal samples, 500 micron sieve processed, from a stratified transect pair. Density Patterns had shore-normal trends, despite apparently weak tidal-cycle environmental gradients. Zones of high abundance of common species persisted unchanged, but seasonal increase and decline occurred within them, with also some population redistribution attributable to differential mortality/recruitment, or possibly to migration. Correlation analysis did not detect interspecies relationships linked to the abundance and zonation of the common polychaetes, all deposit-feeders. The population dynamics of six species was investigated from the transect-pair seasonal samples, supplemented by subsequent more finely-sieved samples during dense recruitment periods. The maldanid Axiothella serrata had three identifiable age groups O, I, and II+, with I plus II+ density to about 550 m-2. The new O group began to appear in October-November, as aggregates below 3 cm sediment depth, believed to represent lecithotropic, direct-developing, siblings from egg masses of the II+ group. Juvenile setiger-total frequencies indicated synchronous adult spawning occurred at varying intervals during an approximate six month period. Peak density of dispersed, near-surface recruits reached 29 thousand m-2. Setiger-total was the most sensitive indicator of size and age in juveniles of up to about 15 setigers. Zonation patterns were age specific. The predominantly lower-shore capitellid, Heteromastus filiformis had a short summer spawning period with settlement ending before May, when population density was up to 10 thousand m-2. Merger of O group into the adult size range occurred in about one year, and probably first spawning was at the end of the second year, with life span of three years or more. The nereidid Nicon aestuariensis had I+ and older age groups at barely detectable densities. Spawning was probably in late summer although an O group, at about 500 m-2, was not detected until May. The spionid Scolecolepides benhami had apparently unchanging size structure and density (about 400 m-2 transect-wide); new settlement was not detected. High density occurred only in a narrow near-shore strip. Nicon aestuariensis also declined down-shore, but more gradually. The spionid Microspio sp. and capitellid Capitella sp. were short-lived, near-surface species, with apparently continuous recruitment from planktotrophic and direct-development respectively. A spring recruitment increase created at first a separate modal group of juveniles, and raised Microspio sp. density to 45 thousand m-2 and Capitella sp. to 7 thousand m-2. Capitella sp. declined in density downshore, but Microspio sp. was only weakly zoned. The common polychaetes had largely concordant density cycles with settlement (or peak settlement) spring-summer orientated, although 500 micron mesh processing detected the peak of surviving adults in autumn-winter. Pauatahanui polychaetes as an assemblage, life history traits, links between population structure and zonation, and problems in polychaete population studies are discussed.</p>

scholarly journals Population Ecology Studies on Infaunal Polychaetes of Pauatahanui Inlet

2021 ◽  
Author(s):  
◽  
Geoffrey Bernard Read
Keyword(s):  
Size Structure ◽  
Environmental Gradients ◽  
Age Groups ◽  
Differential Mortality ◽  
Intertidal Flat ◽  
Adult Size ◽  
Spawning Period ◽  
Near Surface ◽  
Pair Density ◽  
The Common

<p>Macrofaunal polychaete densities across a stable, fine-sand, intertidal flat in Pauatahanui Inlet were examined from a set of seasonal samples, 500 micron sieve processed, from a stratified transect pair. Density Patterns had shore-normal trends, despite apparently weak tidal-cycle environmental gradients. Zones of high abundance of common species persisted unchanged, but seasonal increase and decline occurred within them, with also some population redistribution attributable to differential mortality/recruitment, or possibly to migration. Correlation analysis did not detect interspecies relationships linked to the abundance and zonation of the common polychaetes, all deposit-feeders. The population dynamics of six species was investigated from the transect-pair seasonal samples, supplemented by subsequent more finely-sieved samples during dense recruitment periods. The maldanid Axiothella serrata had three identifiable age groups O, I, and II+, with I plus II+ density to about 550 m-2. The new O group began to appear in October-November, as aggregates below 3 cm sediment depth, believed to represent lecithotropic, direct-developing, siblings from egg masses of the II+ group. Juvenile setiger-total frequencies indicated synchronous adult spawning occurred at varying intervals during an approximate six month period. Peak density of dispersed, near-surface recruits reached 29 thousand m-2. Setiger-total was the most sensitive indicator of size and age in juveniles of up to about 15 setigers. Zonation patterns were age specific. The predominantly lower-shore capitellid, Heteromastus filiformis had a short summer spawning period with settlement ending before May, when population density was up to 10 thousand m-2. Merger of O group into the adult size range occurred in about one year, and probably first spawning was at the end of the second year, with life span of three years or more. The nereidid Nicon aestuariensis had I+ and older age groups at barely detectable densities. Spawning was probably in late summer although an O group, at about 500 m-2, was not detected until May. The spionid Scolecolepides benhami had apparently unchanging size structure and density (about 400 m-2 transect-wide); new settlement was not detected. High density occurred only in a narrow near-shore strip. Nicon aestuariensis also declined down-shore, but more gradually. The spionid Microspio sp. and capitellid Capitella sp. were short-lived, near-surface species, with apparently continuous recruitment from planktotrophic and direct-development respectively. A spring recruitment increase created at first a separate modal group of juveniles, and raised Microspio sp. density to 45 thousand m-2 and Capitella sp. to 7 thousand m-2. Capitella sp. declined in density downshore, but Microspio sp. was only weakly zoned. The common polychaetes had largely concordant density cycles with settlement (or peak settlement) spring-summer orientated, although 500 micron mesh processing detected the peak of surviving adults in autumn-winter. Pauatahanui polychaetes as an assemblage, life history traits, links between population structure and zonation, and problems in polychaete population studies are discussed.</p>

Persistence of giants: population dynamics of the limpet Scutellastra laticostata on rocky shores in Western Australia

2020 ◽  
Vol 646 ◽  
pp. 79-92
Author(s):  
RE Scheibling ◽  
R Black
Keyword(s):  
Population Dynamics ◽  
Western Australia ◽  
Size Structure ◽  
Survival Rates ◽  
Maximum Size ◽  
High Rate ◽  
Adult Survival ◽  
Rocky Shores ◽  
Adult Size ◽  
Decadal Time Scale

Population dynamics and life history traits of the ‘giant’ limpet Scutellastra laticostata on intertidal limestone platforms at Rottnest Island, Western Australia, were recorded by interannual (January/February) monitoring of limpet density and size structure, and relocation of marked individuals, at 3 locations over periods of 13-16 yr between 1993 and 2020. Limpet densities ranged from 4 to 9 ind. m-2 on wave-swept seaward margins of platforms at 2 locations and on a rocky notch at the landward margin of the platform at a third. Juvenile recruits (25-55 mm shell length) were present each year, usually at low densities (<1 m-2), but localized pulses of recruitment occurred in some years. Annual survival rates of marked limpets varied among sites and cohorts, ranging from 0.42 yr-1 at the notch to 0.79 and 0.87 yr-1 on the platforms. A mass mortality of limpets on the platforms occurred in 2003, likely mediated by thermal stress during daytime low tides, coincident with high air temperatures and calm seas. Juveniles grew rapidly to adult size within 2 yr. Asymptotic size (L∞, von Bertalanffy growth model) ranged from 89 to 97 mm, and maximum size from 100 to 113 mm, on platforms. Growth rate and maximum size were lower on the notch. Our empirical observations and simulation models suggest that these populations are relatively stable on a decadal time scale. The frequency and magnitude of recruitment pulses and high rate of adult survival provide considerable inertia, enabling persistence of these populations in the face of sporadic climatic extremes.

scholarly journals COVID-19 Shuts Doors to Flu but Keeps Them Open to Rhinoviruses

Biology ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 733
Author(s):  
Irina Kiseleva ◽  
Andrey Ksenafontov
Keyword(s):  
Influenza Pandemic ◽  
Age Groups ◽  
Influenza Viruses ◽  
Interferon Response ◽  
Chronic Obstructive ◽  
Obstructive Pulmonary Disease ◽  
Mild Disease ◽  
Viral Interference ◽  
The Common

It is well known that rhinoviruses are distributed across the globe and are the most common cause of the common cold in all age groups. Rhinoviruses are widely considered to be harmless because they are generally perceived as respiratory viruses only capable of causing mild disease. However, they may also infect the lower respiratory tract, inducing chronic obstructive pulmonary disease and exacerbations of asthma, bronchiolitis, etc. The role of rhinoviruses in pathogenesis and the epidemiological process is underestimated, and they need to be intensively studied. In the light of recent data, it is now known that rhinoviruses could be one of the key epidemiological barriers that may influence the spread of influenza and novel coronaviruses. It has been reported that endemic human rhinoviruses delayed the development of the H1N1pdm09 influenza pandemic through viral interference. Moreover, human rhinoviruses have been suggested to block SARS-CoV-2 replication in the airways by triggering an interferon response. In this review, we summarized the main biological characteristics of genetically distinct viruses such as rhinoviruses, influenza viruses, and SARS-CoV-2 in an attempt to illuminate their main discrepancies and similarities. We hope that this comparative analysis will help us to better understand in which direction research in this area should move.

Pattern of major injuries after motorcycle accidents in Egypt: The Mansoura Emergency Hospital experience

Trauma ◽  
2016 ◽  
Vol 19 (1) ◽  
pp. 39-45 ◽  
Author(s):  
El Yamani Fouda ◽  
Mohamed Youssef ◽  
Sameh H Emile ◽  
Hossam Elfeki ◽  
Waleed Thabet ◽  
...  
Keyword(s):  
Road Traffic ◽  
Head Injuries ◽  
Age Groups ◽  
Road Traffic Injuries ◽  
Emergency Hospital ◽  
Chest Injuries ◽  
The Common ◽  
Orthopedic Injuries ◽  
Motorcycle Accidents ◽  
Motorcycle Crashes

Background and aim Motorcycle accidents are one of the leading causes of road traffic injuries and mortality. The aim of this study was to determine the common patterns of major injuries associated with motorcycle accidents in patients attending Mansoura University Emergency Hospital in Egypt, and to measure the magnitude of the problem in our community. Patients and methods Patients involved in motorcycle crashes who were admitted to the hospital during August 2014 to April 2015 were retrospectively reviewed. All age groups and both genders were included. Results Two hundred patients (181 males) with a mean age of 30.7 ± 10.5 years were included with the majority of patients aged 20–40 years. Head injuries were the most frequent fatal injuries (9/61) patients; orthopedic injuries were the most common injuries, occurring in 78.5% of victims. Multisystem injuries occurred in 28% of patients. None of the motorcyclists involved in accidents wore helmets. Conclusion Motorcycle accidents are a common cause of road traffic injuries and mortalities in Egypt, occurring mainly in males aged 20–40 years. The majority of victims had an isolated trauma to single body system. Orthopedic injuries were the most common and least fatal type of injuries. The highest fatalities were among patients with chest injuries then patients with head injuries. None of the victims wore protective clothing or helmets at the time of accident.

scholarly journals Time perception and age

2016 ◽  
Vol 74 (4) ◽  
pp. 299-302 ◽  
Author(s):  
Vanessa Fernanda Moreira Ferreira ◽  
Gabriel Pina Paiva ◽  
Natália Prando ◽  
Carla Renata Graça ◽  
João Aris Kouyoumdjian
Keyword(s):  
Time Perception ◽  
Healthy Subjects ◽  
Age Groups ◽  
Internal Clock ◽  
Time Interval ◽  
Comparison Test ◽  
Clock System ◽  
Multiple Comparison Test ◽  
The Common ◽  
Bonferroni Multiple Comparison Test

ABSTRACT Our internal clock system is predominantly dopaminergic, but memory is predominantly cholinergic. Here, we examined the common sensibility encapsulated in the statement: “time goes faster as we get older”. Objective To measure a 2 min time interval, counted mentally in subjects of different age groups. Method 233 healthy subjects (129 women) were divided into three age groups: G1, 15-29 years; G2, 30-49 years; and G3, 50-89 years. Subjects were asked to close their eyes and mentally count the passing of 120 s. Results The elapsed times were: G1, mean = 114.9 ± 35 s; G2, mean = 96.0 ± 34.3 s; G3, mean = 86.6 ± 34.9 s. The ANOVA-Bonferroni multiple comparison test showed that G3 and G1 results were significantly different (P < 0.001). Conclusion Mental calculations of 120 s were shortened by an average of 24.6% (28.3 s) in individuals over age 50 years compared to individuals under age 30 years.

scholarly journals Starvation in childhood and obesity in senior age

2017 ◽  
Vol 8 (6) ◽  
pp. 56-61
Author(s):  
Lidya P. Khoroshinina ◽  
Alexander V. Shabrov ◽  
Leonid G. Buynov
Keyword(s):  
Comparison Group ◽  
Age Groups ◽  
Older Age ◽  
Obesity Prevalence ◽  
Obese People ◽  
The World ◽  
Comparison Groups ◽  
Subcutaneous Layer ◽  
The Common ◽  
Severe Degree

The problem of children's starvation remains relevant and actual at the present time, as in the 21st century experts from the leading countries of the world coordinate their efforts to create programs aimed at eliminating extreme poverty and hunger of. At the same time, the analysis of obesity prevalence typical for the population of some countries of the world, indicates an increase in the number of obese people in both economically developed and developing countries. In this article we are talking about the common severe degree of abdominal obesity in people of older age groups, survivors in childhood, long periods of fasting. Studied 594 history and Protocol of autopsy of people in older age groups, born from 1927 to 1941 and the dead on the hospital for war veterans in St. Petersburg from 1989 to 2000. The whole array of documents was structured by sex, age, the fact of living in the blockaded Leningrad. Severe degree of obesity was considered to be exceeded more than 7 cm of thickness of deep abdominal subcutaneous layer of adipose tissue. It is well established that former young residents of the besieged Leningrad, regardless of gender, age, die sooner than men and women in the comparison groups; men who survived long periods of starvation in children, were dying earlier than men in the comparison group and earlier than women of the main group; women who have experienced a long period of starvation before the age of 11 years, often dying because of cardiovascular diseases than women in the corresponding subgroup comparisons; the emergence of pronounced obesity in older age-governmental groups from the former young residents of the blockaded Leningrad, determined by elk not only the fact of prolonged fasting, but child sex and age, which accounted for starvation.

Clinical Characteristics, Complications, and Reasons for Readmission following Lingual Tonsillectomy

2019 ◽  
Vol 160 (4) ◽  
pp. 619-621 ◽  
Author(s):  
Catherine Merna ◽  
Harrison W. Lin ◽  
Neil Bhattacharyya
Keyword(s):  
Obstructive Sleep Apnea ◽  
Clinical Characteristics ◽  
Age Groups ◽  
Complication Rates ◽  
Indications For Surgery ◽  
Lingual Tonsil ◽  
Obstructive Sleep ◽  
Lingual Tonsillectomy ◽  
The Common ◽  
Indications And Complications

This brief communication regards the indications and complications for and rates of readmission following lingual tonsillectomy. The National Readmissions Database (NRD) 2013-2014 was queried for all cases of lingual tonsillectomy occurring from 2013 to 2014. Among 602 lingual tonsillectomies (mean age 36.5 years, 58.2% male), the common indications for surgery were obstructive sleep apnea (58.7%), lingual tonsil hypertrophy/infection (18.8%), and neoplasia (15.9%). Overall, 49 (8.2%) of the cases were readmitted (95% confidence interval, 4.8%-13.5%), with an average readmission duration of 3.0 days and average readmission cost of $25.4K. The most common diagnoses at readmission were bleeding (1.9% of all lingual tonsillectomy cases); dysphagia (1.7%); fever, nausea, vomiting, or diarrhea (1.6%); acute pain (1.6%); and airway obstruction (1.4%). There were no mortalities during primary or subsequent admissions. Lingual tonsillectomy across age groups is relatively free of adverse events, with overall readmission and complication rates similar to those of palatine tonsillectomy.

scholarly journals Clinical Study on Patients with Grossly Elevated Erythrocyte Sedimentation Rate

1970 ◽  
Vol 8 (2) ◽  
pp. 64-68
Author(s):  
Md Zahirul Haque ◽  
Saki Md Jakiul Alam ◽  
Mesbahuddin Noman ◽  
MA Azhar
Keyword(s):  
Age Groups ◽  
Haematological Malignancies ◽  
Monthly Income ◽  
Connective Tissue Disorders ◽  
College Hospital ◽  
Common Cause ◽  
Medical College ◽  
Erythrocyte Sedimentation ◽  
The Common ◽  
Body Ache

This study was done in medicine indoor department of Rajshahi Medical College Hospital from January 2004 to March 2004. Consecutive 100 patients, who were advised to test the ESR by their physicians for their complaints and found to have an ESR, equal to or more than 100 mm in 1st hour, were included in this study. Among 100 patients 56 were male and 44 were female. All of them were classified in five age groups. They were also categorized according to their monthly income and occupation. Fever, generalized weakness, weight loss, pallor, pain, body ache were the common presenting complaints. Haematological disorder appeared to be most common cause (41%) of marked ESR elevation; followed by infectious diseases (36%) and connective tissue disorders (17%). Among the all patients 30% cases were haematological malignancies (i.e. acute myeloblastic and lymphoblastic leukaemia, lymphomas, multiple myeloma). In 4% cases the cause could not be elicited.    DOI = 10.3329/jom.v8i2.1411 J MEDICINE 2007; 8 : 64-68

scholarly journals The common oro-dental problems among patients attending Ohud dental care and implant center at Bogra, Bangladesh

2016 ◽  
Vol 5 (1) ◽  
pp. 15-20
Author(s):  
S Hoque ◽  
I Jahan
Keyword(s):  
Dental Care ◽  
Inflammatory Disease ◽  
Inflammatory Diseases ◽  
Age Groups ◽  
Food Habit ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Level Of Knowledge ◽  
The Common ◽  
The Difference

A descriptive type of cross sectional study on exploring the common oro-dental problems among the patients attending outpatient department of Ohud Dental Care and implant center, Bogra was conducted during the period from May to July’ 2013. The objectives of this study were to identify the common oro-dental problems for assessing the level of knowledge regarding dental care practices among the respondents. A questionnaire based data were collected and the sample compares 414 respondents of all age groups. The highest percentage of the patients had complaints of periodontitis (73.9%) followed by gingivitis (64.3%), dental caries (40.6%), attrition (10.4%), mobility (5.8%), broken teeth (5.6%) and alveolar abscess (6.3%). Considering the pattern of inflammation, 425.5% had inflammatory or-dental problems and 56.6% had non-inflammatory oro-dental problems. On examination also revealed that 3 1.9% unhealthy gums, 3.9% had unhealthy tonsils, 10.3% had diseased tongue, 10.7% had diseases mucosa and 4.1% had apthus ulcer. The proportion of illiterate patients were higher among the inflammatory disease (16.7%) compared to non-inflammatory disease (9.8%), where as respondents having graduate level of education were higher among the non- inflammatory disease (30.8%) compared to inflammatory diseases (8.3%). There was significant association between the oro-dental problems and food habit (p>O.O5) except liking of sweet and habit of area nut and lime (p<O.05). This indicated that the proportion of non-inflammatory dental problems were higher among the patients habituate with sweet (82.5%) compared to inflammatory disease (72.2%). But the proportion of inflammatory disease was higher among the patients having habituated with chewing areca nut line (35.0%) than non- inflammatory disease (26.1%). Knowledge of causes of dental problems higher among the patients having non-inflammatory disease (62.0%) compared to inflammatory disease (46.7%) and the difference was statistically significant (p<O.001). Similarly, the proportion of visiting dental surgeon was significantly (p<0.001) higher among the patients having non-inflammatory disease (4.4%).International Journal of Natural Sciences (2015), 5(1) 15-20

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