Effect of Changes in Breast-feeding on the Age Distribution of HTLV-I Carriers Using a Mathematical Model

SUMMARYThe processes which govern the age structure of Fasciola hepatica populations in sheep were investigated by means of a simple mathematical model. The mortality of the metacercariae on the pasture was shown to be a factor of major importance. The mortality rate depends on the micro-climate that prevails at the pasture surface, and thus the age distribution curve of a population of flukes is also determined in part by the weather. This has important implications for the chemotherapy of fascioliasis: flukicides are not equally effective over the whole range of age-classes of parasite and so the factors which govern the age distribution curve of the parasite population within individual hosts ultimately determine the efficiency of chemotherapy.

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Malaria prevalence amongst Brazilian Indians assessed by a new mathematical model

Epidemiology and Infection ◽

10.1017/s0950268800057253 ◽

1993 ◽

Vol 111 (3) ◽

pp. 525-538 ◽

Cited By ~ 6

Author(s):

M. N. Burattini ◽

E. Massad ◽

F. A. B. Coutinho ◽

R. G. Baruzzi

Keyword(s):

Mathematical Model ◽

Control Strategies ◽

Age Distribution ◽

Malaria Prevalence ◽

Reproductive Rate ◽

Force Of Infection ◽

Age Related ◽

Serological Data

SummaryAn alternative way to estimate the endemic level of malaria amongst Brazilian indians is proposed. This is achieved by estimating the age-related “force of infection’ of malaria (the effective inoculation rate), applying a mathematical model, described elsewhere, to serological data. In addition we present a way to estimate the Basic Reproductive Rate of malaria in the same area. The results have shown a good degree of accuracy in describing the endemic pattern of malaria in the area, and also indicate some relevant aspects of its age distribution related to the design of control strategies.

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A Cross Sectional Study on Assessing the Relationship Between Prenatal Complications and Delay in Breast Feeding in New Born Babies

Journal of University of Shanghai for Science and Technology ◽

10.51201/jusst/21/09687 ◽

2021 ◽

Vol 23 (10) ◽

pp. 281-294

Author(s):

Shalini S ◽

◽

Gopalakrishnan S ◽

Abiselvi A ◽

Madhura Vani B ◽

...

Keyword(s):

Breast Feeding ◽

Health Care Providers ◽

Mode Of Delivery ◽

Child Survival ◽

Age Distribution ◽

Early Initiation ◽

World Health ◽

Baby Friendly Hospital Initiative ◽

Care Providers ◽

Cross Sectional

The Baby friendly hospital initiative was launched in the year 1991 -1992, by World Health Organization and UNICEF, in around 156 countries throughout the world with a goal to ensure initiation of breast feeding in all infant before their discharge from the hospital. The hospitals which implemented Ten recommendations for successful breast feeding were designed as Baby Friendly Hospitals. By strengthening of this as initiative in the community, a better child survival can be achieved. A revised and expanded version of baby friendly hospital initiative was implemented by WHO and UNICEF in the year 2009. This study is carried out to estimate the prevalence of early initiation of breast feeding, the reasons for its delay in hospitals in and around Chennai. The age distribution among the study population was ranged between 18 to 40 years. The mean age was 24.6 years. Out of 450 mothers 84.2% of mothers were between 21 – 30 years, 11.1% of mothers were less than 20 years and 4.7% of mothers were more than 30 years. This study shows that there is a significant association between mode of delivery and initiation of breast feeding. The prevalence of early initiation of breast feeding among normal deliveries and caesarean deliveries was 71.3% and 41.5% respectively. This study was supported by the study done by Ashmika Motee et al (2013) which reveals that 42.6% of normally delivered mothers and 23.9% of caesarean delivered mothers had initiated breast feeding within one hour. For caesarean delivered mothers, management of pain along with support of family members and health care providers, helps in early initiation of breast feeding.

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New Approaches to Ceramic Use and Discard: Cooking Pottery from the Peruvian Andes in Ethnoarchaeological Perspective

Latin American Antiquity ◽

10.2307/972209 ◽

1999 ◽

Vol 10 (1) ◽

pp. 25-46 ◽

Cited By ~ 15

Author(s):

John A. Hildebrand ◽

Melissa B. Hagstrum

Keyword(s):

Mathematical Model ◽

Age Distribution ◽

Family Members ◽

Household Consumption ◽

Household Size ◽

Regional Survey ◽

Peruvian Andes ◽

New Approaches ◽

Ceramic Vessel ◽

Large Families

AbstractEthnoarchaeological data from contemporary Wanka villages in the Mantaro Valley of the Peruvian Andes provide new perspectives on the use and discard of ceramic cooking vessels. We present a regional survey of ceramic vessel use and discard with household consumption as the focus of study. A mathematical model determines vessel uselife from the age distribution of in-use vessels. We examine the number of vessels per household, their volume, their uselife, and their reported discard. A typical Wanka household cooking vessel assemblage consists of four or five ollas, two large ollas, one chata, and one tostadera. As family members are added to a household, the number of household ollas slightly increases, as does olla volume and the overall rate of olla discard. Large families have fewer chatas, and the rate of chata discard is uncorrelated with household size. Large and small families alike have only one tostadera, but in large families, a shortened tostadera uselife increases their discard rate. Distributing the same population into small or large households will result in significantly different rates of total sherd accumulation. Bulk sherd accumulation is a better indicator of the number of households rather than of the total number of persons. Household size can be estimated from the relative proportions of discarded ollas, chatas, and tostaderas.

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How immunity from and interaction with seasonal coronaviruses can shape SARS-CoV-2 epidemiology

10.1101/2021.05.27.21257032 ◽

2021 ◽

Author(s):

Naomi R Waterlow ◽

Edwin Van Leeuwen ◽

Nicholas G Davies ◽

Stefan Flasche ◽

Rosalind M Eggo ◽

...

Keyword(s):

Mathematical Model ◽

Age Distribution ◽

Cross Protection ◽

Surveillance Data ◽

England And Wales ◽

Seasonal Epidemics ◽

Potential Impact ◽

Human Coronaviruses

We hypothesised that cross-protection from seasonal epidemics of human coronaviruses (HCoVs) could have affected SARS-CoV-2 transmission, including generating reduced susceptibility in children. To determine what the pre-pandemic distribution of immunity to HCoVs was, we fitted a mathematical model to 6 years of seasonal coronavirus surveillance data from England and Wales. We estimated a duration of immunity to seasonal HCoVs of 7.3 years (95%CI 6.8 - 7.9) and show that, while cross-protection between HCoV and SARS-CoV-2 may contribute to the age distribution, it is insufficient to explain the age pattern of SARS-CoV-2 infections in the first wave of the pandemic in England and Wales. Projections from our model illustrate how different strengths of cross-protection between circulating coronaviruses could determine the frequency and magnitude of SARS-CoV-2 epidemics over the coming decade, as well as the potential impact of cross-protection on future seasonal coronavirus transmission.

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Steady State Performance of Activated Carbon Contactors

Water Science & Technology ◽

10.2166/wst.1991.0622 ◽

1991 ◽

Vol 23 (7-9) ◽

pp. 1677-1686 ◽

Cited By ~ 5

Author(s):

U. K. Traegner ◽

M. T. Suidan

Keyword(s):

Mathematical Model ◽

Particle Size ◽

Activated Carbon ◽

Steady State ◽

Surface Diffusion ◽

Age Distribution ◽

Carbon Surface ◽

Transfer Resistance ◽

Homogeneous Surface ◽

Component Representation

A mathematical model for the steady state adsorption of pollutants from completely mixed activated carbon contactors is derived in this paper. In order to accurately describe these processes, a sludge age distribution is incorporated for the adsorbent. The resulting mathematical model is solvable analytically using the homogeneous surface diffusion model (HSDM) as a descriptor of intraparticle mass transfer resistance. Various examples are included in this paper to illustrate the use of this new derivation. Effects of particle size, particle size distribution of commercial carbon, surface diffusion coefficients, and solids mass flow rate, on the performance of the completely mixed adsorption system are studied in detail. Examples of multicomponent, competitive adsorption as well as an equivalent single component representation of a target component are discussed.

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A Study on post partum breast problems of mothers attending at lactation management center (LMC)

Bangladesh Medical Journal ◽

10.3329/bmj.v44i3.27372 ◽

2016 ◽

Vol 44 (3) ◽

pp. 136-139

Author(s):

Sharmin Akter ◽

Saria Tasnim ◽

Mohammad Monzurul Alam Bhuiyan ◽

Amanat Hasan

Keyword(s):

Breast Feeding ◽

Post Partum ◽

Age Distribution ◽

Inverted Nipple ◽

Proper Position ◽

Working Mother ◽

Exclusive Breast Feeding ◽

Lactating Mothers ◽

Timing Of Initiation

Exclusive breast feeding is essential for the physical and mental development of the child. Post-partum breast problem may produce a obstacle on the way of successful breast feeding. So this study was conducted in ICMH, Matuail to find out common post-partum breast problems. All mothers attending at LMC after delivery with breast problems were included in the study. A total 114 samples were taken. All lactating mothers who gave their consent are to be included in the study and who are not willing to participate in the study were excluded. In our study, age distribution of mother shows, 35.96% of mothers were at the age of < 20 years, 58.77% were between 20-30 years and 5.26% were > 30 yrs of age. Among 114 patients, 91.22% of mothers were house wife and 8.77% were working Mother, timing of initiation of breastfeeding was, 12.28% initiated within 1 hours, 78.28% were within 1-12 hours, 4.38% were within 12-24 hours and exclusive breast feeding was given to 63.15% baby and first pre-lacteal feed was given to 36.84%, among them 71.42%. Common problem was, 46.49% mother suffered from not enough milk followed by, 20.17% for poor attachment, 17.54% suffered from breast engorgement and 7.89% suffered cracked nipple, inverted nipple was in 2.63% flat and sore nipple to 1.75% and nipple infection and breast abscess was present in 0.877% mothers. Among them, 100% mother were counseled about breast feeding, 78.95% mother were taught about proper position and attachment, hot or cold compression given to 35.09%, Oketani breast massage given to 30.7% and others to 13.16%. In our study all mothers were counseled on the benefit of breastfeeding at LMC. Further large long term cohort study should be carried out to see the postpartum breast problem during lactation.Bangladesh Med J. 2015 Sep; 44 (3): 136-139

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How immunity from and interaction with seasonal coronaviruses can shape SARS-CoV-2 epidemiology

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2108395118 ◽

2021 ◽

Vol 118 (49) ◽

pp. e2108395118

Author(s):

Naomi R. Waterlow ◽

Edwin van Leeuwen ◽

Nicholas G. Davies ◽

Stefan Flasche ◽

Rosalind M. Eggo ◽

...

Keyword(s):

Mathematical Model ◽

Severe Acute Respiratory Syndrome ◽

Age Distribution ◽

Cross Protection ◽

Surveillance Data ◽

England And Wales ◽

Seasonal Epidemics ◽

Potential Impact ◽

Human Coronaviruses

We hypothesized that cross-protection from seasonal epidemics of human coronaviruses (HCoVs) could have affected severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission, including generating reduced susceptibility in children. To determine what the prepandemic distribution of immunity to HCoVs was, we fitted a mathematical model to 6 y of seasonal coronavirus surveillance data from England and Wales. We estimated a duration of immunity to seasonal HCoVs of 7.8 y (95% CI 6.3 to 8.1) and show that, while cross-protection between HCoV and SARS-CoV-2 may contribute to the age distribution, it is insufficient to explain the age pattern of SARS-CoV-2 infections in the first wave of the pandemic in England and Wales. Projections from our model illustrate how different strengths of cross-protection between circulating coronaviruses could determine the frequency and magnitude of SARS-CoV-2 epidemics over the coming decade, as well as the potential impact of cross-protection on future seasonal coronavirus transmission.

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Gradual acquisition of immunity to severe malaria with increasing exposure

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2014.2657 ◽

2015 ◽

Vol 282 (1801) ◽

pp. 20142657 ◽

Cited By ~ 50

Author(s):

Jamie T. Griffin ◽

T. Déirdre Hollingsworth ◽

Hugh Reyburn ◽

Chris J. Drakeley ◽

Eleanor M. Riley ◽

...

Keyword(s):

Mathematical Model ◽

Plasmodium Falciparum ◽

Cerebral Malaria ◽

Severe Malaria ◽

Severe Disease ◽

Age Distribution ◽

Physiological Changes ◽

Careful Monitoring ◽

African Countries ◽

Multiple Episodes

Previous analyses have suggested that immunity to non-cerebral severe malaria due to Plasmodium falciparum is acquired after only a few infections, whereas longitudinal studies show that some children experience multiple episodes of severe disease, suggesting that immunity may not be acquired so quickly. We fitted a mathematical model for the acquisition and loss of immunity to severe disease to the age distribution of severe malaria cases stratified by symptoms from a range of transmission settings in Tanzania, combined with data from several African countries on the age distribution and overall incidence of severe malaria. We found that immunity to severe disease was acquired more gradually with exposure than previously thought. The model also suggests that physiological changes, rather than exposure, may alter the symptoms of disease with increasing age, suggesting that a later age at infection would be associated with a higher proportion of cases presenting with cerebral malaria regardless of exposure. This has consequences for the expected pattern of severe disease as transmission changes. Careful monitoring of the decline in immunity associated with reduced transmission will therefore be needed to ensure rebound epidemics of severe and fatal malaria are avoided.

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