Life Table Approach Research Articles

Evaluation of Long-term Outcomes and Prediction of Failure Rate of Endoscopic Third Ventriculostomy in Less Than 2 Years Children

Background: The study carried out to assess long-term outcomes of endoscopic third ventriculostomy (ETV) on less than two years of hydrocephalous children and to determine prognostic factors of ETV success in this population. Methods: our study was a retrospective cohort study carried out on 40 hydrocephalus children who underwent ETV surgery. Clinical data retrieved from patient’s medical records, and we did an active follow-up. We used Kaplan-Meier and life-table approaches to assess 6 months success rate of ETV. We also used multiple cox regression to determine prognostic factors associated with success. Moreover, the ROC curve analysis was used to assess how ETV success score (ETVSS) can predict the possibility of ETV failure. Results: The mean age of patients at surgery time was 7.8 (±7.8) months, and 60% were male. The mean failure time of ETV was 4.5 months, and the most common etiology was aqueduct (27.0%). According to our finding age at surgery time (hazard ratio [HR]=2.2, 95% CI=1.1, 3.4) and birth age (HR=4.4, 95% CI 1.1, 17.2) were the main factors associated with ETV failure. We also observed, statistically lower HR for patients with aqueduct etiology (HR=0.1, 95% CI=0.01, 0.9). Moreover, the area under the ROC curve was estimated at 76.1, illustrating partial validity to predict ETV failure in the study population. Conclusion: According to our findings, ETV could suggest treating Hydrocephaly in young kids with particular attention on over 6-month patients and those who were mature at birth. However, more studies are required to confirm our findings.

Burden of mortality attributed to PM2.5 exposure in cities of Iran; contribution of short-term pollution peaks

The objective of this study was to determine the population exposure to PM2.5, and to quantify the effect of eliminating short-term pollution peaks on the number of cause-specific deaths, the number of years of life lost (YLL), and economic losses attributed to exposure to PM2.5 in 25 Iranian cities with available air quality data. Number of deaths and YLL were estimated with AirQ + software tool using available concentration-response functions and life table approach. Furthermore, the value of lost life in each city were calculated using the Value of Statistical Life (VSL) method. Two scenarios were defined; Scenario A, considering actual observed concentrations to estimate the real health effects of PM2.5, and Scenario B, controlling for the effect of air pollution episodes. The results showed that the annual average concentrations of PM2.5 in cities were 1.5–6.1 times higher than the guideline value of WHO (10 μg/m³). The total number of all-cause deaths due to long-term exposure exceeding WHO air quality guideline level was 13321 (95% C.I.: 8837–17378) cases per year in all cities. The total numbers of chronic obstructive pulmonary disease (COPD), lung cancer, ischemic heart disease (IHD), and stroke deaths attributed to the exposure were 274, 315, 1536, and 963 cases, respectively. The total number of YLL over 10 years period in all 25 cities was 486,289 years and the loss of life expectancy ranged from 0.43 to 1.87 years. The sum of economic losses due to lost life exceeded 5.8 billion USD. Except for some cities, avoiding highly polluted days in Scenario B would result in only 5% reduction in overall health or economic effects. These results indicate an urgent need for new comprehensive plans to tackle air pollution in Iranian cities focused on reduction of long term average pollution levels since programs for avoiding highly polluted days lead to a limited health benefits only.

Twin Births and Their Survival under Age Five: Evidence from Bangladesh Demographic and Health Survey 2014

Background & Aim: Little is known about twinning in developing countries due to lack of reliable data. However, the large data set from the national level Demographic and Health Surveys (DHSs) in developing countries can fill this gap. This paper examines the level, trends and determinants of twin births, and their risk of survival until age five relative to singletons in Bangladesh. Methods & Materials: The data for the study were obtained from the 2014 Bangladesh DHS. The analysis was based on birth histories of 43,842 live births, experienced by the 17,863 women between 1978 and until survey date November 2014. Frequency distribution, cross tabulation, univariate and multivariate logistic regression models, and demographic methods such as conventional life table approach were used for data analysis. Results: About 1.52% of the total live births in Bangladesh were found found to be twins. The twin birth rate has increased by 13.4% over the last 20 years in Bangladesh. Maternal age, parity, region of residence, economic status, father’s education, contraceptive use status and religion were identified as significant predictors of twin births. Twinning appeared as a significant predictor of high childhood mortality. Twins were found to have more than eight times higher risk of death during neonatal period than that of singletons. Conclusion: The increasing trends in twin births in Bangladesh and the associated higher risk of childhood mortality among twins underscores the need for more focused care strategy during pregnancy and after birth. Further studies are needed to identify the reasons for exceptionally high childhood mortality among twins in Bangladesh.

Why do women discontinue contraception and what are the post-discontinuation outcomes? Evidence from the Arusha Region, Tanzania

In Africa, high discontinuation of contraceptive use is thwarting goals for healthy birth spacing or limiting childbearing. This paper investigates how well the contraception program is addressing the needs of women and couples in the Arusha region, Tanzania by studying contraceptive use continuation. We measured the overall and method-specific discontinuation rate, reasons for discontinuation, post-discontinuation reproductive behaviours/outcomes, and examined the determinants of contraceptive discontinuation. We used data from a household survey conducted in Arusha from January to May 2018. Information on contraceptive use during the 31 months preceding the survey was recorded in a monthly calendar. Using the single- and multiple-decrement life-table approach, we calculated the overall and cause-specific discontinuation of contraceptive methods. Logistic regression was used to evaluate the determinants of discontinuation. The 12-month overall discontinuation of contraceptive use was 44.6%. Discontinuation was lowest for implants (12.3%) and highest for male condoms (60.1%), the most common reason being side effects (11.7%). 59.8% of women who discontinued did not switch to another method within 3 months following discontinuation and 20.9% experienced pregnancy. Longer distance to a health facility is associated with higher discontinuation of hormonal methods such as injectables, but lower discontinuation of non-hormonal methods such as condoms. Discontinuation due to side effects is not explained by most of the women’s background characteristics other than the method they used. Discontinuation of contraception is high among Arusha women. Effective contraception programs, especially improved counselling, need to address the reasons for the discontinuation of contraceptive use.

Toxicity and sublethal effects of two plant allelochemicals on the demographical traits of cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae).

Plant allelochemicals are a group of secondary metabolites produced by plants to defend against herbivore. The mortality of two plant allelochemicals (tannic acid and gossypol) on the cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae), were investigated using feeding assays and the sublethal effects were evaluated using the age-stage, two-sex life table approach. Tannic acid and gossypol have deleterious effects on A. gossypii, and as the concentrations increased, the mortality of cotton aphid increased. The life history traits of A. gossypii including the developmental duration of each nymph stage, the longevity, oviposition days, total preadult survival rate and adult pre-oviposition period were not significantly affected by sublethal concentration of tannic acid (20 mg/L) and gossypol (50 mg/L), while the population parameters (r, λ and R0) were significantly affected by these two plant allelochemicals. Furthermore, tannic acid can increase the pre-adult duration time and TPOP but reduce the fecundity of A. gossypii significantly compared to the control and gossypol treatment groups. These results are helpful for comprehensively understanding the effects of plant allelochemicals on A. gossypii.

Impact of depressive symptoms on worklife expectancy: a longitudinal study on Danish employees

ObjectiveDepressive symptoms are associated with sickness absence, work disability and unemployment, but little is known about worklife expectancy (WLE). This study investigates the impact of depressive symptoms on the WLE...

Abstract 2415: Polygenic risk-tailored screening for prostate cancer: A cost-effectiveness analysis

Abstract Background Screening for prostate cancer with prostate specific antigen (PSA) remains controversial. Risk-tailoring based on age and polygenic profile might conserve the benefits of PSA screening whilst reducing overdiagnosis. This study evaluates the cost-effectiveness and benefit-to-harm balance of polygenic risk-tailored screening for prostate cancer. Methods A life-table approach was used. A hypothetical cohort of 4.48 million men in England between the ages of 55 and 70 was followed to the age of 90. Three scenarios were compared: no screening, age-based screening (PSA testing every four years from 55 to 70), and risk-tailored screening based on age and polygenic risk profile (men above the risk threshold receive PSA testing four-yearly from the age they reach the risk threshold to 70). The number of prostate cancer cases, deaths from prostate cancer, overdiagnosed cases, life-years and quality-adjusted life-years (QALYs), incremental cost per QALY, and net monetary benefit were calculated. Sensitivity analyses investigated the impact of parameter uncertainty, and the impact of varying the risk threshold, on outcomes. Costs were estimated from the perspective of the UK National Health Service; both costs and benefits were discounted at 3.5%. Results The incremental cost per additional QALY for age-based screening compared to no screening was £58,254 ($75,899), with 27% simulations having an incremental cost-effectiveness ratio of less than £20,000 ($26,058), the threshold set by the UK National Institute for Health and Care Excellence for an intervention to be considered cost-effective. In risk-tailored screening, as the 10-year absolute risk-threshold was progressively increased from 2.6%, equivalent to the 10-year absolute risk of a 55-year old man, to 7.1%, the corresponding risk of a 69-year old man, the cost per additional QALY gained reduced from £36,065 ($46,989) to £26,210 ($34,149), when compared to no screening. By comparison with age-based screening, risk-tailored screening with a threshold between 2.6% and 7.1% led to 8 (2.5%) and 45 (13%) fewer deaths prevented from prostate cancer per 10,000 men, with a 0.1% rise and 10% reduction in costs, respectively. Raising the risk threshold from 2.6% to 7.1% led to fewer men being screened (cumulative total of 35% of men screened by comparison with 83%), 53% fewer overdiagnosed cases, 22% fewer biopsies and 10% lower costs, at the expense of 10% fewer prostate cancer deaths averted. Conclusion Risk-tailored screening reduces the harms of screening for prostate cancer whilst preserving much of the mortality benefit. This study raises the prospect of risk-tailored population-based screening for prostate cancer; the precise risk-thresholds selected will depend on societal judgements regarding the appropriate trade-offs between harms and benefits. Citation Format: Thomas Callender, Mark Emberton, Steve Morris, Ros Eeles, Zsofia Kote-Jarai, Paul Pharoah, Nora Pashayan. Polygenic risk-tailored screening for prostate cancer: A cost-effectiveness analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2415.

The Interannual Changes in the Secondary Production and Mortality Rate of Main Copepod Species in the Gulf of Gdańsk (The Southern Baltic Sea)

The main objective of this paper was description of seasonal and interannual trends in secondary production and mortality rates of the three most important Copepoda taxa in the Gulf of Gdańsk (southern Baltic Sea). Samples were collected monthly from six stations located in the western part of the Gulf of Gdańsk during three research periods: 1998–2000, 2006–2007, and 2010–2012. Production was calculated based on copepod biomass and mortality rates estimated according to vertical life table approach. Redundancy analysis was used to investigate relationship between secondary production and environmental conditions. During the entire research period there was significant interannual and seasonal variability of secondary production, mortality rate, as well as abundance and biomass anomalies. Conducted analysis revealed positive correlation between increasing temperature and production of Acartia spp. and Temora longicornis developmental stages, while older copepodites of Pseudocalanus acuspes showed almost negative correlation with temperature. The mortality rate estimations obtained for Acartia spp. were the highest in summer, while Temora longicornis peaked in spring–summer period. The lowest mortality rate estimations were noted in autumn and winter for almost all stages of investigated taxa.

Racial and Educational Disparities in Dementia and Dementia-Free Life Expectancy.

We estimate life expectancy with and without dementia for Americans 65 years and older by education and race to examine how these stratification systems combine to shape disparities in later-life cognitive health. Based on the Health and Retirement Study (2000-2014), we use a multivariate, incidence-based life table approach to estimate life expectancy by cognitive health status for race-education groups. The models also simulate group differences in the prevalence of dementia implied by these rates. The life table results document notable race-education differences in dementia and dementia-free life expectancy, as well as stark differences in implied dementia prevalence. At each education level, blacks can expect to live more years with dementia and they have significantly higher rates of dementia prevalence. This distribution of disparities in the older population is anchored by 2 groups-blacks without a high school diploma and whites with some college or more. Dementia experience and dementia burden differ dramatically along race-education lines. Race and education combine to exaggerate disparities and they both have enduring effects. Future research should explicitly consider how race and education combine to influence dementia in the older American population.

Fitness costs of sulfoxaflor resistance in the cotton aphid, Aphis gossypii Glover

Aphis gossypii Glover is an economically important pest of numerous crops throughout the world. Some field populations of A.gossypii in China have developed moderate level of resistance to sulfoxaflor, a newly released sulfoximine insecticide for management of sap-feeding pests. To evaluate the effect of sulfoxaflor resistance on the fitness cost of A. gossypii, the life history traits of sulfoxaflor-resistant strain (SulR) and an isogenic susceptible strain (SS) were compared using the age-stage, two-sex life table approach. The results showed that the resistant strain had a reduction in fitness (relative fitness = 0.917), along with significantly decreases in longevity, fecundity, net reproductive (R0), mean generation time (T) and gross reproductive rate (GRR). Compared to the susceptible strain, SulR strain showing a shorter developmental duration of each nymph instar stage. Moreover, the adult pre-oviposition period (APOP) and total preoviposition period (TPOP) of SulR strain were also significantly shorter than that of the susceptible strain. Investigation of six development and reproduction related genes indicated that EcR, USP and JHBP were overexpressed in the SulR strain, while the mRNA transcript level of Vg was decreased significantly compared to the susceptible strain. These results suggest that there is a fitness cost associated with sulfoxaflor resistance in A. gossypii and the different expression of EcR, USP, JHBP, and Vg may play very important role in this trade-off.

Serious adverse events and lifetime risk of reoperation after elective shoulder replacement: population based cohort study using hospital episode statistics for England

ObjectivesTo provide accurate risk estimates of serious adverse events after elective shoulder replacement surgery for arthritis, including age and sex specific estimates of the lifetime risk of revision surgery.DesignPopulation based...

Transgenerational hormetic effects of sublethal dose of flupyradifurone on the green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae).

Both inhibitory and stimulatory (known as hormesis) effects of the sublethal flupyradifurone, a butenolide insecticide, on Myzus persicae Sulzer (Hemiptera: Aphididae) were investigated for incorporating it into integrated pest management (IPM). A leaf-dip bioassay showed that flupyradifurone was very toxic against adult M. persicae with a 48 h LC50 of 8.491 mg/L. Using the age-stage two-sex life table approach, we assessed the effects of LC25 of flupyradifurone on adult M. persicae and its progeny (F1 and F2). On the one hand, aphids exposed to flupyradifurone had significantly negative effects on the life history traits acrossing the generations, such as reduced the adult longevity and fecundity of F0, shortened the duration of third instar and fourth instar nymphs, preadult period and the pre-reproductive period of F1, and decreased the reproductive days and adult longevity of F2. On the other hand, stimulatory effects on the duration of pre-adult, adult reproductive days, and reproduction of F1 were observed in the flupyradifurone-treated aphids. Consistently with the stimulation on individual traits, a higher net reproductive rate (R0) of F1 and a shorter mean generation time (T) of F2 were observed in the flupyradifurone-treated aphids, although the other population parameters including the intrinsic rate of increase (r), finite rate of increase (λ) and T of F1 and R0, r and λ of F2 were not significantly affected. These results revealed that adult M. persicae exposed to sublethal concentration of flupyradifurone can induce hormetic effects on F1, and also cause negative effects on F2. Our results would be useful for assessing the overall effects of flupyradifurone on M. persicae and the hormetic effects should take into consideration when use flupyradifurone for control M. persicae.

Growing Trend in Application of Age-Stage, Two-Sex Life Table Theory in Diverse Ecological and Pest Management Studies

Life table is an effective tool for characterizing the demography of an arthropod to understand the phenomenon in pest population development which is a key for developing IPM strategy. Age-stage, two-sex life tables provide comprehensive insights into the stage differentiation of an arthropods, compared with the traditional female age-specific life tables and any other forms of life tables. The age-stage, two-sex life table approach is applied in diverse type of ecological and pest management research. This article is intended to draw attention of Nepalese researchers towards the significance of demographic studies for development of IPM strategy, advancements in application of age-stage, two-sex life table approach and its computer programs. Altogether more than 694 peer reviewed papers and PhD theses have been published since 1988. Out of this, 92 papers were sampled and reviewed for this paper. In such papers, demography of diverse 50 species of arthropods classified under 27 different families belonging to 10 orders have been studied using this theory to measure their fitness in diverse food and environment condition, to assess their consumption, predation or parasitism capacity and to project their population growth in different scenario, to forecast the timing of control based on the stage structure of pest populations and to be used in mass rearing and harvesting of predators and preys under biological control program.

State-level diabetes-attributable mortality and years of life lost in the United States

PurposeTo estimate state-level diabetes-attributable deaths and years of life lost (YLL) in the Unites States. MethodsWe estimated diabetes-attributable all-cause and cardiovascular disease (CVD) deaths by age, sex, and state, using the attributable fraction approach. Data on diabetes prevalence were collected from Behavioral Risk Factor Surveillance System. Relative risks for people with and without diabetes were estimated using the National Health Interview Survey. State-sex-age–specific deaths were obtained from CDC WONDER. YLL were calculated by multiplying the number of people with diabetes by the difference in life expectancy between people with and without diabetes using the life table approach. ResultsNationally, estimated diabetes-attributable all-cause deaths and CVD deaths were 293,224 and 90,953, respectively. Diabetes resulted in a total of 109,707,000 YLL with an average 4.4 years of life lost per person with diabetes. Most state variation in total deaths was explained by state population size and diabetes prevalence. All-cause deaths ranged from 415 in Alaska to 28,538 in California, and CVD deaths ranged from 113 in Alaska to 8908 in California. Across all states, the average diabetes-attributable death rate per 100,000 was 125 for males and 105 for females for all-cause deaths and 40 for males and 31 for females for CVD deaths. ConclusionsMortality attributable to diabetes is greatly underestimated when looking only at diabetes listed as an underlying cause of death. These results can be used to track state differences in deaths due to diabetes and to monitor the success of public health activities.

Religion, Life Expectancy, and Disability-Free Life Expectancy Among Older Women and Men in the United States.

Existing literature shows religion is associated with health and survival separately. We extend this literature by considering health and survival together using a multistate life table approach to estimate total, disability-free, and disabled life expectancy (LE), separately for women and men, for 2 disability measures, and by 2 indicators of religion. Data come from the Health and Retirement Study (1998-2014 waves). Predictors include importance of religion and attendance at religious services. The disability measures are defined by ADLs and IADLs. Models control for sociodemographic and health covariates. Attendance at religious services shows a strong and consistent association with life and health expectancy. Men and women who attend services at least once a week (compared with those who attend less frequently or never) have between 1.1 and 5.1 years longer total LE and between 1.0 and 4.3 years longer ADL disability-free LE. Findings for IADL disability are similar. Importance of religion is related to total and disabled LE (both ADL and IADL), but the differentials are smaller and less consistent. Controlling for sociodemographic and health factors does not explain these associations. By estimating total, disability-free, and disabled LE, we are able to quantify the advantage of religion for health. Results are consistent with previous studies that have focused on health and mortality separately.

The relationship between healthy life expectancy and smoking, hypertension and body mass index in a Japanese population: A multistate life table method using Nippon Data90

Introduction Healthy life expectancy (HLE) is an important measure for describing population health. Human factors such as smoking, hypertension, and obesity can reduce overall HLE in a population. Little is known about the relationship between HLE and cardiovascular risk factors in Asian populations. Our study aimed to estimate HLE in various combinations of cardiovascular risk factors in a Japanese population using a multistate life table approach. Methods Data were obtained from NIPPON DATA90, which is a nationwide cohort study of nine thousand Japanese people that was established in 1990. From among the NIPPON DATA90 participants, our analysis focused on people who were aged 60 years or older at the baseline survey and had received activities of daily living (ADL) assessment. Participants underwent a two-wave interview survey process using the Katz ADL index in 1995 and 2000. The participants were queried on five items of the Katz ADL index, and any participant who answered that they were “not independent” for at least one item was designated “disabled” in the multistate life table. Smoking status was categorized into non-smokers (never-/ex-smokers) and current smokers. Blood pressure (BP) was categorized into four groups (optimal, normal, stage 1 hypertension, and stage 2 hypertension). Obesity was defined using body mass index (BMI), which was categorized into three groups (thin: 18.5; normal: 18.5–24.9; and overweight/obese: ≥ 25). All HLE calculations were performed using iMaCh version 0.98r7 (A Maximum Likelihood Computer Program using Interpolation of Markov Chains). Results The study sample comprised 6676 participants (2840 men and 3836 women). Among all the BMI and BP groups, HLE at age 60 in current smokers was shorter than that of non-smokers. Among obese men with optimal BP, HLE in current smokers was 20.0 years, whereas that of non-smokers was 17.7 years. Among obese current smokers, HLE at age 60 decreased linearly as BP increased in men (optimal BP: 19.8 years, normal BP: 19.3 years, stage 1 hypertension: 18.1 years, stage 2 hypertension: 17.7 years) and women (optimal BP: 23.1 years, normal BP: 22.6 years, stage 1 hypertension: 21.4 years, stage 2 hypertension: 21.0 years). Among thin current smokers, HLE at age 60 also decreased linearly as BP increased in men (optimal BP: 18.3 years, normal BP: 17.8 years, stage 1 hypertension: 16.6 years, stage 2 hypertension: 16.3 years) and women (optimal BP: 21.8 years, normal BP: 21.2 years, stage 1 hypertension: 19.9 years, stage 2 hypertension: 19.6 years). The distribution of HLE at age 60 showed a slight inverted U-shape as BMI increased in both sexes. Conclusions We examined the relationship between HLE at age 60 and combinations of BMI, BP, and smoking status using a nationwide cohort study of the Japanese population. HLE at age 60 was clearly shorter in smokers and individuals with higher BP. Furthermore, both thin and obesity has a slight impact on HLE at age 60.

Mortality of Calanus helgolandicus: Sources, differences between the sexes and consumptive and nonconsumptive processes

AbstractWhile losses from mortality are as important as gains from reproduction in zooplankton population dynamics, the former are more challenging to quantify. We used two approaches to provide complementary insights into the mortality of a biomass‐dominant copepod, Calanus helgolandicus, at Station L4 in the English Channel. Using a neutral‐red staining method, we found that dead carcasses represented a mean of 9% of the C. helgolandicus copepodites sampled. The resulting nonconsumptive mortality rates are the first that have been derived for C. helgolandicus; and estimates suggest a contribution of 0–54% (median of 4.4%) to the total mortality rate. Consumptive mortality (i.e., that due to removal by predation), dominated for most of the year and contributed a mean of 89% to total mortality. Nonconsumptive mortality increased during summer and winter, and was positively related to maximum wind speed during the preceding 72 h, indicating that extreme weather events may lead to increased mortality. Using the Vertical Life Table approach, mortality rates across the CV‐adult male stage pair were on average ∼ 2.5 times greater than those of CV‐adult females. Adult male consumptive mortality rates were ∼ 6 times greater than those for females; adult male nonconsumptive rates were twice those of females, suggesting that predation is of greater significance to male loss rates. Summer CV‐adult mortality rates were positively correlated to temperature, and to the abundance of predatory chaetognaths and siphonophores, suggesting that the gelatinous predator assemblage is the dominant agent for population control of late stage copepodites of C. helgolandicus at L4.

Fitness cost of nitenpyram resistance in the brown planthopper Nilaparvata lugens

A resistant strain of Nilaparvata lugens has been continuously selected in the presence of nitenpyram for 27 generations under laboratory conditions in order to study the fitness cost of nitenpyram resistance. The resistance to nitenpyram in N. lugens was at a high level (resistance ratio = 144.7-fold). Life-tables of the nitenpyram-resistant strain and the susceptible strain (SS) of N. lugens were studied by using the age-stage, two-sex life-table approach. Compared to the SS, the relative fitness of the resistant strain of N. lugens was 0.55, with a lower intrinsic rate of increase (r) and net reproductive rate (R0). Changes in some life-history traits of the resistant strain were also observed. The duration of the egg stage, the development times of the first-, third- and fourth-instar nymphs, the adult preoviposition period and the total preoviposition period of the resistant strain were significantly increased, whereas the longevity, egg survival rate and fecundity (eggs/female) (absolute fitness) were significantly decreased in the resistant strain of N. lugens. The lower intrinsic rate of increase (r) and net reproductive rate (R0) seemed to be largely due to number of eggs laid, developmental time and egg survival rate. These results showed that the development of nitenpyram resistance may lead to significant fitness costs in resistant populations of N. lugens. This study provided valuable information for facilitating the development of nitenpyram-resistance management strategies.

The gains in life expectancy by ambient PM2.5 pollution reductions in localities in Nigeria.

Global burden of disease estimates reveal that people in Nigeria are living shorter lifespan than the regional or global average life expectancy. Ambient air pollution is a top risk factor responsible for the reduced longevity. But, the magnitude of the loss or the gains in longevity accruing from the pollution reductions, which are capable of driving mitigation interventions in Nigeria, remain unknown. Thus, we estimate the loss, and the gains in longevity resulting from ambient PM2.5 pollution reductions at the local sub-national level using life table approach. Surface average PM2.5 concentration datasets covering Nigeria with spatial resolution of ∼1 km were obtained from the global gridded concentration fields, and combined with ∼1 km gridded population of the world (GPWv4), and global administrative unit layers (GAUL) for territorial boundaries classification. We estimate the loss or gains in longevity using population-weighted average pollution level and baseline mortality data for cardiopulmonary disease and lung cancer in adults ≥25 years and for respiratory infection in children under 5. As at 2015, there are six "highly polluted", thirty "polluted" and one "moderately polluted" States in Nigeria. People residing in these States lose ∼3.8-4.0, 3.0-3.6 and 2.7 years of life expectancy, respectively, due to the pollution exposure. But, assuming interventions achieve global air quality guideline of 10 μg/m3, longevity would increase by 2.6-2.9, 1.9-2.5 and 1.6 years for people in the State-categories, respectively. The longevity gains are indeed high, but to achieve them, mitigation interventions should target emission sources having the highest population exposures.

Construction of nuptiality tables for the hilly rural population of Uttarakhand: 1931-2000

Background: Nuptiality has a strong association with socio demographic and socio economic change in society. So, it has immense importance to study the female age at marriage in society. In order to study the nuptiality pattern in rural areas of Uttarakhand State, India, a number of measures like crude marriage rate, age sex specific marriage rates and similar other rates are used in the nuptiality tables.Methods: This paper deals with the study on the change in the nuptiality pattern through the life table approach in the seven cohorts 1931-40, 1941-50, 1951-60, 1961-70, 1971-80, 1981-90 and 1991-2000. It is observed that the rates are changing with time. We also calculate expected number of years of single life remaining to a single person at age x. It is also observed that the age at marriage is increasing as the time passes. The data for this has been collected through the primary collection technique and the paper includes all the nuptiality tables for the seven cohort systems.Results: It is observed that the rates are changing with time. No significant time trend has been observed in the nuptiality rates among the single population of hilly rural area of Uttarakhand. From the table we can see that initially, at the age group 10 the rate is small and it increases rapidly till it reaches to maximum at the age group 20.Conclusions: In the field of marriage for the Indian population, it is suggested that development and examination of nuptiality tables over various periods would constitute a distinct progression in the investigation of Indian nuptiality.