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Sample records for age-matched control population

  1. Assessment of the cardiac autonomic neuropathy among the known diabetics and age-matched controls using noninvasive cardiovascular reflex tests in a South-Indian population: A case–control study

    PubMed Central

    Sukla, Pradeep; Shrivastava, Saurabh RamBihariLal; Shrivastava, Prateek Saurabh; Rao, Nambaru Lakshmana

    2016-01-01

    Aim: Diabetes mellitus is a chronic condition characterized by hyperglycemia. The objective of the study was to estimate the prevalence of cardiac autonomic neuropathy in a rural area of South India, among the known diabetics after comparing them with the age-matched healthy controls, utilizing noninvasive cardiac autonomic neuropathy reflex tests. Materials and Methods: A case–control study was conducted for 4 months (October 2014 to January 2015) at an Urban Health and Training Center (UHTC) of a Medical College located in Kancheepuram district, Tamil Nadu. The study was conducted among 126 diagnosed Type 2 diabetes patients and in 152 age- and sex-matched healthy controls to ensure comparability between the cases and controls and, thus, reduce variability due to demographic variables. All the study subjects (cases and controls) were selected from the patients attending UHTC during the study duration, provided they satisfied the inclusion and exclusion criteria. Study participants were subjected to undergo noninvasive cardiac autonomic neuropathy reflex tests. The associations were tested using paired t-test for the continuous (mean ± standard deviation) variables. Results: The overall prevalence of cardiac autonomic neuropathy among diabetic patients was found to be as 53.2% (67/126). On further classification, positive (abnormal) results were obtained in 56 (sympathetic – 44.4%) and 51 (parasympathetic – 40.5%) diabetic cases. Overall, heart rate variation during deep breathing was found to be the most sensitive test to detect parasympathetic autonomic neuropathy while the diastolic blood pressure response to sustained handgrip exercise was the most sensitive method to detect sympathetic neuropathy dysfunction. Conclusion: The overall prevalence of cardiac autonomic neuropathy among diabetic patients was found to be as 53.2%. Even though cardiac autonomic neuropathy can be detected by various invasive tests, noninvasive tests remain a key tool to detect

  2. Age-Matched, Case-Controlled Comparison of Clinical Indicators for Development of Entropion and Ectropion

    PubMed Central

    Michels, Kevin S.; Czyz, Craig N.; Cahill, Kenneth V.; Foster, Jill A.; Burns, John A.; Everman, Kelly R.

    2014-01-01

    Purpose. To analyze the clinical findings associated with involutional entropion and ectropion and compare them to each other and to age-matched controls. Methods. Prospective, age-matched cohort study involving 30 lids with involutional entropion, 30 lids with involutional ectropion, and 52 age-matched control lids. Results. The statistically significant differences associated with both the entropion and ectropion groups compared to the control group were presence of a retractor dehiscence, presence of a “white line,” occurrence of orbital fat prolapse in the cul-de-sac, decreased lower lid excursion, increased lid laxity by the snapback test, and an increased lower lid distraction. Entropion also differed from the control group with an increased lid crease height and decreased lateral canthal excursion. Statistically significant differences associated with entropion compared to ectropion were presence of a retractor dehiscence, decreased lateral canthal excursion, and less laxity in the snapback test. Conclusion. Entropic and ectropic lids demonstrate clinically and statistically significant anatomical and functional differences from normal, age-matched lids. Many clinical findings associated with entropion are also present in ectropion. Entropion is more likely to develop with a pronounced retractor deficiency. Ectropion is more likely to develop with diminished elasticity as measured by the snapback test. PMID:24734167

  3. Comparison of Conditioning Impairments in Children with Down Syndrome, Autistic Spectrum Disorders and Mental Age-Matched Controls

    ERIC Educational Resources Information Center

    Reed, P.; Staytom, L.; Stott, S.; Truzoli, R.

    2011-01-01

    Background: This study investigated the relative ease of learning across four tasks suggested by an adaptation of Thomas's hierarchy of learning in children with Down syndrome, autism spectrum disorders and mental age-matched controls. Methods: Learning trials were carried out to investigate observational learning, instrumental learning, reversal…

  4. Pitch Characteristics Before Ulnar Collateral Ligament Reconstruction in Major League Pitchers Compared With Age-Matched Controls

    PubMed Central

    Prodromo, John; Patel, Nimit; Kumar, Neil; Denehy, Kevin; Tabb, Loni Philip; Tom, James

    2016-01-01

    Background: Ulnar collateral ligament reconstruction (UCLR) is commonly performed in Major League Baseball (MLB) pitchers, but little is known about the preoperative pitch type and velocity characteristics of pitchers who go on to undergo UCLR. Hypothesis: Pitchers who required UCLR have thrown a greater percentage of fastballs and have greater pitch velocities compared with age-matched controls in the season before injury. Study Design: Case-control study; Level of evidence, 3. Methods: MLB pitchers active during the 2002 to 2015 seasons were included. The UCLR group consisted of MLB pitchers who received UCLR between 2003 and 2015, utilizing the season before surgery (2002-2014) for analysis. The control group comprised age-matched controls of the same season. Players who pitched less than 20 innings in the season before surgery were excluded. Pitch types were recorded as percentage of total pitches thrown. Pitch velocities were recorded for each pitch type. Pitch type and pitch velocities during preoperative seasons for UCLR pitchers were compared with age-matched controls using univariate and multivariate models. Results: A total of 114 cases that went on to UCLR and 3780 controls were included in the study. Pitchers who went on to UCLR appear to have greater fastball, slider, curveball, changeup, and split-fingered fastball velocities; there were no significant differences in pitch selection between the 2 groups. Conclusion: In the season before surgery, MLB pitchers who underwent UCLR demonstrated greater fastball, slider, curveball, changeup, and split-fingered fastball velocities, with no significant difference in pitch type. PMID:27350954

  5. Prematurely Delivered Rats Show Improved Motor Coordination During Sensory-evoked Motor Responses Compared to Age-matched Controls

    PubMed Central

    Roberto, Megan E.; Brumley, Michele R.

    2014-01-01

    The amount of postnatal experience for perinatal rats was manipulated by delivering pups one day early (postconception day 21; PC21) by cesarean delivery and comparing their motor behavior to age-matched controls on PC22 (the typical day of birth). On PC22, pups were tested on multiple measures of motor coordination: leg extension response (LER), facial wiping, contact righting, and fore- and hindlimb stepping. The LER and facial wiping provided measures of synchronous hind- and forelimb coordination, respectively, and were sensory-evoked. Contact righting also was sensory-evoked and provided a measure of axial coordination. Stepping provided a measure of alternated forelimb and hindlimb coordination and was induced with the serotonin receptor agonist quipazine. Pups that were delivered prematurely and spent an additional day in the postnatal environment showed more bilateral limb coordination during expression of the LER and facial wiping, as well as a more mature righting strategy, compared to controls. These findings suggest that experience around the time of birth shapes motor coordination and the expression of species-typical behavior in the developing rat. PMID:24680729

  6. Oral contraceptive use among female elite athletes and age-matched controls and its relation to low back pain.

    PubMed

    Brynhildsen, J; Lennartsson, H; Klemetz, M; Dahlquist, P; Hedin, B; Hammar, M

    1997-10-01

    Exogenous and endogenous female sex steroids may influence the risk of low back pain. The fact that back pain is a very common symptom during pregnancy supports this theory. Back pain is also more common among female than male athletes. Oral contraceptives have been suggested to increase the risk of low back pain. The aim of this study was to evaluate whether the prevalence of low back pain is higher among oral contraceptive users than non-users and if it differs between women taking part in different sports. A questionnaire was sent to female elite athletes in volleyball (n = 205), basketball (n = 150), and soccer (n = 361) as well as to age-matched controls (n = 113). The questionnaire comprised questions about age, constitution, occupation, parity, and use of contraceptive method as well as previous and current back pain and possible consequences of the back problems. The response rate was 85%. Between 42% and 52% of the women in the different groups used oral contraceptives. The groups were similar in most background variables, except that the volleyball and basketball players were taller. The prevalence of current low back pain was between 21% and 34% in the different athlete groups, with an average of 30%, whereas only 18% of the controls suffered from low back pain (p 0.01). The prevalence of low back pain within each group--athletes as well as controls--was similar in women who used and did not use oral contraceptives. This study does not support the theory that low back pain is affected by the use of oral contraceptives. Instead, constitutional factors and mechanical stress during intense physical activity are probably more important.

  7. Preserved Learning during the Symbol–Digit Substitution Test in Patients with Schizophrenia, Age-Matched Controls, and Elderly

    PubMed Central

    Cornelis, Claudia; De Picker, Livia J.; Hulstijn, Wouter; Dumont, Glenn; Timmers, Maarten; Janssens, Luc; Sabbe, Bernard G. C.; Morrens, Manuel

    2015-01-01

    Objective: Speed of processing, one of the main cognitive deficits in schizophrenia is most frequently measured with a digit–symbol-coding test. Performance on this test is additionally affected by writing speed and the rate at which symbol–digit relationships are learned, two factors that may be impaired in schizophrenia. This study aims to investigate the effects of sensorimotor speed, short-term learning, and long-term learning on task performance in schizophrenia. In addition, the study aims to explore differences in learning effects between patients with schizophrenia and elderly individuals. Methods: Patients with schizophrenia (N = 30) were compared with age-matched healthy controls (N = 30) and healthy elderly volunteers (N = 30) during the Symbol–Digit Substitution Test (SDST). The task was administered on a digitizing tablet, allowing precise measurements of the time taken to write each digit (writing time) and the time to decode symbols into their corresponding digits (matching time). The SDST was administered on three separate days (day 1, day 2, day 7). Symbol–digit repetitions during the task represented short-term learning and repeating the task on different days represented long-term learning. Results: The repetition of the same symbol–digit combinations within one test and the repetition of the test over days resulted in significant decreases in matching time. Interestingly, these short-term and long-term learning effects were about equal among the three groups. Individual participants showed a large variation in the rate of short-term learning. In general, patients with schizophrenia had the longest matching time whereas the elderly had the longest writing time. Writing time remained the same over repeated testing. Conclusion: The rate of learning and sensorimotor speed was found to have a substantial influence on the SDST score. However, a large individual variation in learning rate should be taken into account in the

  8. RELN-expressing Neuron Density in Layer I of the Superior Temporal Lobe is Similar in Human Brains with Autism and in Age-Matched Controls

    PubMed Central

    Camacho, Jasmin; Ejaz, Ehsan; Ariza, Jeanelle; Noctor, Stephen C.; Martínez-Cerdeño, Verónica

    2015-01-01

    Reelin protein (RELN) level is reduced in the cerebral cortex and cerebellum of subjects with autism. RELN is synthesized and secreted by a subpopulation of neurons in the developing cerebral cortex termed Cajal-Retzius (CR) cells. These cells are abundant in the marginal zone during cortical development, many die after development is complete, but a small population persists into adulthood. In adult brains, RELN is secreted by the surviving CR cells, by a subset of GABAergic interneurons in layer I, and by pyramidal cells and GABAergic interneurons in deeper cortical layers. It is widely believed that decreased RELN in layer I of the cerebral cortex of subjects with autism may result from a decrease in the density of RELN expressing neurons in layer I; however, this hypothesis has not been tested. We examined RELN expression in layer I of the adult human cortex and found that 70% of cells express RELN in both control and autistic subjects. We quantified the density of neurons in layer I of the superior temporal cortex of subjects with autism and age-matched control subjects. Our data show that there is no change in the density of neurons in layer I of the cortex of subjects with autism, and therefore suggest that reduced RELN expression in the cerebral cortex of subjects with autism is not a consequence of decreased numbers of RELN-expressing neurons in layer I. Instead reduced RELN may result from abnormal RELN processing, or a decrease in the number of other RELN-expressing neuronal cell types. PMID:25067827

  9. Evaluation of Basal Renal Function in Treatment-naïve Patients with Malignancy and Comparison with Age Matched Healthy Control

    PubMed Central

    Barai, Sukanta; Gambhir, Sanjay; Jain, Suruchi; Rastogi, Neeraj

    2016-01-01

    There is a paucity of data regarding the prevalence of renal insufficiency in patients with malignancy at baseline before initiation of therapy. The published studies based on patient with prior exposure to cytotoxic therapy have reported a high prevalence of renal impairment. However, these studies have utilized creatinine-based glomerular filtration rate (GFR) prediction equations to assess the level of renal function. These equations are known to have some serious limitations in reliably predicting GFR. The aim of the study was to accurately document the state of renal function in treatment-naïve cancer patients and compare them against age-matched healthy controls using a reference “creatinine independent” GFR measurement technique. Age-matched comparison of GFR of 1,373 treatment-naïve cancer patients and 1,089 healthy controls were done retrospectively. There was no difference in GFR between cancer and healthy group when analyzed under various age groups, though the overall mean GFR in healthy controls was significantly higher compared to cancer group (80.14 ± 17.63 mL vs 74.43 ± 20.84, P 0≤ 0.01), whereas the mean age in control arm was significantly lower compared to cancer group (44.24 ± 17.63 years vs. 50.70 ± 20.84 years, P ≤ 0.01). Treatment-naïve cancer patients have identical renal function to their healthy age-matched peers. Malignancy per se does not directly lead to the decline in filtration capacity of the kidneys. PMID:27651734

  10. Evaluation of Basal Renal Function in Treatment-naïve Patients with Malignancy and Comparison with Age Matched Healthy Control

    PubMed Central

    Barai, Sukanta; Gambhir, Sanjay; Jain, Suruchi; Rastogi, Neeraj

    2016-01-01

    There is a paucity of data regarding the prevalence of renal insufficiency in patients with malignancy at baseline before initiation of therapy. The published studies based on patient with prior exposure to cytotoxic therapy have reported a high prevalence of renal impairment. However, these studies have utilized creatinine-based glomerular filtration rate (GFR) prediction equations to assess the level of renal function. These equations are known to have some serious limitations in reliably predicting GFR. The aim of the study was to accurately document the state of renal function in treatment-naïve cancer patients and compare them against age-matched healthy controls using a reference “creatinine independent” GFR measurement technique. Age-matched comparison of GFR of 1,373 treatment-naïve cancer patients and 1,089 healthy controls were done retrospectively. There was no difference in GFR between cancer and healthy group when analyzed under various age groups, though the overall mean GFR in healthy controls was significantly higher compared to cancer group (80.14 ± 17.63 mL vs 74.43 ± 20.84, P 0≤ 0.01), whereas the mean age in control arm was significantly lower compared to cancer group (44.24 ± 17.63 years vs. 50.70 ± 20.84 years, P ≤ 0.01). Treatment-naïve cancer patients have identical renal function to their healthy age-matched peers. Malignancy per se does not directly lead to the decline in filtration capacity of the kidneys.

  11. Evaluation of Basal Renal Function in Treatment-naïve Patients with Malignancy and Comparison with Age Matched Healthy Control.

    PubMed

    Barai, Sukanta; Gambhir, Sanjay; Jain, Suruchi; Rastogi, Neeraj

    2016-09-01

    There is a paucity of data regarding the prevalence of renal insufficiency in patients with malignancy at baseline before initiation of therapy. The published studies based on patient with prior exposure to cytotoxic therapy have reported a high prevalence of renal impairment. However, these studies have utilized creatinine-based glomerular filtration rate (GFR) prediction equations to assess the level of renal function. These equations are known to have some serious limitations in reliably predicting GFR. The aim of the study was to accurately document the state of renal function in treatment-naïve cancer patients and compare them against age-matched healthy controls using a reference "creatinine independent" GFR measurement technique. Age-matched comparison of GFR of 1,373 treatment-naïve cancer patients and 1,089 healthy controls were done retrospectively. There was no difference in GFR between cancer and healthy group when analyzed under various age groups, though the overall mean GFR in healthy controls was significantly higher compared to cancer group (80.14 ± 17.63 mL vs 74.43 ± 20.84, P 0≤ 0.01), whereas the mean age in control arm was significantly lower compared to cancer group (44.24 ± 17.63 years vs. 50.70 ± 20.84 years, P ≤ 0.01). Treatment-naïve cancer patients have identical renal function to their healthy age-matched peers. Malignancy per se does not directly lead to the decline in filtration capacity of the kidneys. PMID:27651734

  12. A Comparison of Substantia Nigra T1 Hyperintensity in Parkinson's Disease Dementia, Alzheimer's Disease and Age-Matched Controls: Volumetric Analysis of Neuromelanin Imaging

    PubMed Central

    Park, Ju-Yeon; Yun, Won-Sung; Jeon, Ji Yeong; Moon, Yeon Sil; Kim, Heejin; Kwak, Ki-Chang; Lee, Jong-Min; Han, Seol-Heui

    2016-01-01

    Objective Neuromelanin loss of substantia nigra (SN) can be visualized as a T1 signal reduction on T1-weighted high-resolution imaging. We investigated whether volumetric analysis of T1 hyperintensity for SN could be used to differentiate between Parkinson's disease dementia (PDD), Alzheimer's disease (AD) and age-matched controls. Materials and Methods This retrospective study enrolled 10 patients with PDD, 18 patients with AD, and 13 age-matched healthy elderly controls. MR imaging was performed at 3 tesla. To measure the T1 hyperintense area of SN, we obtained an axial thin section high-resolution T1-weighted fast spin echo sequence. The volumes of interest for the T1 hyperintense SN were drawn onto heavily T1-weighted FSE sequences through midbrain level, using the MIPAV software. The measurement differences were tested using the Kruskal-Wallis test followed by a post hoc comparison. Results A comparison of the three groups showed significant differences in terms of volume of T1 hyperintensity (p < 0.001, Bonferroni corrected). The volume of T1 hyperintensity was significantly lower in PDD than in AD and normal controls (p < 0.005, Bonferroni corrected). However, the volume of T1 hyperintensity was not different between AD and normal controls (p = 0.136, Bonferroni corrected). Conclusion The volumetric measurement of the T1 hyperintensity of SN can be an imaging marker for evaluating neuromelanin loss in neurodegenerative diseases and a differential in PDD and AD cases. PMID:27587951

  13. Intensively-Managed Young Children with Type 1 Diabetes Consume High-Fat, Low-Fiber Diets Similar to Age-Matched Controls

    PubMed Central

    Mehta, Sanjeev N.; Volkening, Lisa K.; Quinn, Nicolle; Laffel, Lori M.B.

    2014-01-01

    Despite significant emphasis on nutrition, older children with diabetes demonstrate poor dietary quality. We tested the hypothesis that dietary quality in young children with type 1 diabetes (T1D) would be better than age-matched children in the US population. Dietary data from children with T1D (n=67), ages 2–12 years, attending a pediatric diabetes clinic were compared to a nationally representative, age-matched sample from the National Health and Nutrition Examination Survey (NHANES, n=1691). Multiple 24-hour dietary recalls were used. Recommended intakes were based on national guidelines, and dietary quality was assessed using the Healthy Eating Index-2005 (HEI-2005). More children with T1D were overweight or obese compared to children participating in NHANES (42% vs. 30%, p=0.04). Greater proportions of children with T1D met daily recommendations for vegetables (22% vs. 13%, p=0.03), whole grains (12% vs. 5%, p=0.005), and dairy (55% vs. 36%, p=0.001) compared to NHANES children while similar proportions met daily fruit recommendations (40% vs. 33%, p=0.2). Less than one-third of all children limited total fat to recommended levels; children with T1D consumed more saturated fat than NHANES children (14% vs. 12% total energy intake, p=0.0009). Fiber intakes were very low in both groups. Compared to NHANES children, children with T1D had higher HEI-2005 scores (59.6 vs. 49.7, p=0.0006) primarily due to lower intakes of added sugars. The nutritional intake of young children with T1D remains suboptimal in the contemporary era of diabetes management. Despite focused nutrition management, young children with T1D consume high-fat, low-fiber diets comparable to youth in the general population. PMID:24916556

  14. Functional Aspects of Gait in Essential Tremor: A Comparison with Age-Matched Parkinson’s Disease Cases, Dystonia Cases, and Controls

    PubMed Central

    Louis, Elan D.; Rao, Ashwini K.

    2015-01-01

    Background An understanding of the functional aspects of gait and balance has wide ramifications. Individuals with balance disorders often restrict physical activity, travel, and social commitments to avoid falling, and loss of balance confidence, itself, is a source of disability. We studied the functional aspects of gait in patients with essential tremor (ET), placing their findings within the context of two other neurological disorders (Parkinson’s disease [PD] and dystonia) and comparing them with age-matched controls. Methods We administered the six-item Activities of Balance Confidence (ABC-6) Scale and collected data on number of falls and near-falls, and use of walking aids in 422 participants (126 ET, 77 PD, 46 dystonia, 173 controls). Results Balance confidence was lowest in PD, intermediate in ET, and relatively preserved in dystonia compared with controls. This ordering reoccurred for each of the six ABC-6 items. The number of near-falls and falls followed a similar ordering. Use of canes, walkers, and wheelchairs was elevated in ET and even greater in PD. Several measures of balance confidence (ABC-6 items 1, 4, 5, and 6) were lower in torticollis cases than in those with blepharospasm, although the two groups did not differ with respect to falls or use of walking aids. Discussion Lower balance confidence, increased falls, and greater need for walking aids are variably features of a range of movement disorder patients compared to age-matched controls. While most marked among PD patients, these issues affected ET patients as well and, to a small degree, some patients with dystonia. PMID:26056611

  15. Semiquantitative proteomic analysis of human hippocampal tissues from Alzheimer’s disease and age-matched control brains

    PubMed Central

    2013-01-01

    Background Alzheimer’s disease (AD) is the most common type of dementia affecting people over 65 years of age. The hallmarks of AD are the extracellular deposits known as amyloid β plaques and the intracellular neurofibrillary tangles, both of which are the principal players involved in synaptic loss and neuronal cell death. Tau protein and Aβ fragment 1–42 have been investigated so far in cerebrospinal fluid as a potential AD biomarkers. However, an urgent need to identify novel biomarkers which will capture disease in the early stages and with better specificity remains. High-throughput proteomic and pathway analysis of hippocampal tissue provides a valuable source of disease-related proteins and biomarker candidates, since it represents one of the earliest affected brain regions in AD. Results In this study 2954 proteins were identified (with at least 2 peptides for 1203 proteins) from both control and AD brain tissues. Overall, 204 proteins were exclusively detected in AD and 600 proteins in control samples. Comparing AD and control exclusive proteins with cerebrospinal fluid (CSF) literature-based proteome, 40 out of 204 AD related proteins and 106 out of 600 control related proteins were also present in CSF. As most of these proteins were extracellular/secretory origin, we consider them as a potential source of candidate biomarkers that need to be further studied and verified in CSF samples. Conclusions Our semiquantitative proteomic analysis provides one of the largest human hippocampal proteome databases. The lists of AD and control related proteins represent a panel of proteins potentially involved in AD pathogenesis and could also serve as prospective AD diagnostic biomarkers. PMID:23635041

  16. Sicca symptoms in Thai patients with rheumatoid arthritis, systemic lupus erythematosus and scleroderma: a comparison with age-matched controls and correlation with disease variables.

    PubMed

    Wangkaew, Suparaporn; Kasitanon, Nuntana; Sivasomboon, Chate; Wichainun, Ramjai; Sukitawut, Waraporn; Louthrenoo, Worawit

    2006-12-01

    This study was performed to determine the prevalence of ocular and oral sicca symptoms in Thai patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and scleroderma (Scl). The ocular symptoms and sign (the Schirmer's 1 test) and the oral sicca symptoms and sign (the Saxon's test) in each of 50 RA, SLE and Scl patients were compared with their age-matched controls. The correlation between the presence of sicca symptoms and signs with their clinical activity was also determined. Ocular sicca symptoms were found more common in patients with RA (38% vs 18%, p < 0.05), SLE (36% vs 14%, p < 0.05) and Scl (54% vs 16%, p < 0.01), and oral sicca symptoms were found more common in SLE (22% vs 0%, p < 0.01), and Scl (16% vs 4%, p < 0.05) than their controls. However, only RA patients had a significantly higher proportion of positive Schimer-1 test compared with their controls (p < 0.01). There was no strong correlation between sicca symptoms or signs and other clinical or laboratory variables (age, disease duration, disease activity, disease severity, and antibody to Ro and La antigens) in these three groups. In conclusion, sicca symptoms were seen significantly more common in Thai patients with connective tissue diseases, but the symptoms did not show a good correlation with the clinical and laboratory variables.

  17. Immunity in young adult survivors of childhood leukemia is similar to the elderly rather than age-matched controls: Role of cytomegalovirus.

    PubMed

    Azanan, Mohamad Shafiq; Abdullah, Noor Kamila; Chua, Ling Ling; Lum, Su Han; Abdul Ghafar, Sayyidatul Syahirah; Kamarulzaman, Adeeba; Kamaruzzaman, Shahrul; Lewin, Sharon R; Woo, Yin Ling; Ariffin, Hany; Rajasuriar, Reena

    2016-07-01

    Many treatment complications that occur late in childhood cancer survivors resemble age-related comorbidities observed in the elderly. An immune phenotype characterized by increased immune activation, systemic inflammation, and accumulation of late-differentiated memory CD57(+) CD28(-) T cells has been associated with comorbidities in the elderly. Here, we explored if this phenotype was present in young adult leukemia survivors following an average of 19 years from chemotherapy and/or radiotherapy completion, and compared this with that in age-matched controls. We found that markers of systemic inflammation-IL-6 and human C-reactive protein and immune activation-CD38 and HLA-DR on T cells, soluble CD (sCD)163 from monocytes and macrophages-were increased in survivors compared to controls. T-cell responses specific to cytomegalovirus (CMV) were also increased in survivors compared to controls while CMV IgG levels in survivors were comparable to levels measured in the elderly (>50years) and correlated with IL-6, human C-reactive protein, sCD163, and CD57(+) CD28(-) memory T cells. Immune activation and inflammation markers correlated poorly with prior chemotherapy and radiotherapy exposure. These data suggest that CMV infection/reactivation is strongly correlated with the immunological phenotype seen in young childhood leukemia survivors and these changes may be associated with the early onset of age-related comorbidities in this group. PMID:27129782

  18. Comparison of younger and older breast cancer survivors and age-matched controls on specific and overall QoL domains

    PubMed Central

    Champion, Victoria L.; Wagner, Lynne I.; Monahan, Patrick O.; Daggy, Joanne; Smith, Lisa; Cohee, Andrea; Ziner, Kim W.; Haase, Joan E.; Miller, Kathy; Pradhan, Kamnesh; Unverzagt, Frederick W.; Cella, David; Ansari, Bilal; Sledge, George W.

    2014-01-01

    Background Younger survivors (YS) of breast cancer often report more survivorship symptoms such as fatigue, depression, sexual difficulty, and cognitive problems than older survivors (OS). We sought to determine the effect of breast cancer and age at diagnosis on Quality of Life (QoL) by comparing 3 groups: 1) YS diagnosed at age 45 or before, 2) OS diagnosed between 55 and 70, and, 3) for the YS, age-matched controls (AC) of women not diagnosed with breast cancer. Methods Using a large Eastern Cooperative Oncology Group (ECOG) data base, we recruited 505 YS who were ages 45 or younger when diagnosed and 622 OS diagnosed at 55 to 70. YS, OS, and AC were compared on physical, psychological, social, spiritual, and overall QoL variables. Results Compared to both AC and to OS, YS reported more depressive symptoms (p=.005) and fatigue (p<.001), poorer self-reported attention function (p<.001), and poorer sexual function (p<.001) than either comparison group. However, YS also reported a greater sense of personal growth (p<.001) and perceived less social constraint (p<.001) from their partner than AC. Conclusions YS reported worse functioning than AC relative to depression, fatigue, attention, sexual function, and spirituality. Perhaps even more important, YS fared worse than both AC and OS on body image, anxiety, sleep, marital satisfaction, and fear of recurrence, indicating that YS are at greater risk for long term QoL problems than survivors diagnosed at a later age. PMID:24891116

  19. No Consistent Difference in Gray Matter Volume between Individuals with Fibromyalgia and Age-Matched Healthy Subjects when Controlling for Affective Disorder

    PubMed Central

    Hsu, Michael C.; Harris, Richard E.; Sundgren, Pia C.; Welsh, Robert C.; Fernandes, Carlo R.; Clauw, Daniel J.; Williams, David A.

    2009-01-01

    Fibromyalgia (FM) is thought to involve abnormalities in central pain processing. Recent studies involving small samples have suggested alterations in gray matter volume (GMV) in brains of FM patients. Our objective was to verify these findings in a somewhat larger sample using voxel-based morphometry (VBM), while controlling for presence of affective disorders (AD). T1-weighted magnetic resonance image (MRI) brain scans were obtained on 29 FM patients with AD, 29 FM patients without AD, and 29 age-matched healthy controls (HC) using a 3T scanner. Segmentation, spatial normalization, and volumetric modulation were performed using an automated protocol within SPM5. Smoothed gray matter segments were entered into a voxel-wise one-way ANOVA, and a search for significant clusters was performed using thresholding methods published in previous studies (whole-brain threshold of p<.05 correcting for multiple comparisons; region-of-interest (ROI) threshold of p≤.001 uncorrected, or p<.05 small-volume corrected). The whole-brain analysis did not reveal any significant clusters. ROI-based analysis revealed a significant difference in left anterior insula GMV among the three groups (xyz={−28, 21, 9}; p=.026, corrected). However, on post-hoc testing, FM patients without AD did not differ significantly from HC with respect to mean GMV extracted from this cluster. A significant negative correlation was found between mean cluster GMV and scores of trait anxiety (State-Trait Personality Inventory, Trait Anxiety scale; rho=−.470, p<.001). No other significant clusters were found on ROI-based analysis. Our results emphasize the importance of correcting for AD when carrying out VBM studies in chronic pain. PMID:19375224

  20. Differential gene expression in liver and small intestine from lactating rats compared to age-matched virgin controls detects increased mRNA of cholesterol biosynthetic genes

    PubMed Central

    2011-01-01

    Background Lactation increases energy demands four- to five-fold, leading to a two- to three-fold increase in food consumption, requiring a proportional adjustment in the ability of the lactating dam to absorb nutrients and to synthesize critical biomolecules, such as cholesterol, to meet the dietary needs of both the offspring and the dam. The size and hydrophobicity of the bile acid pool increases during lactation, implying an increased absorption and disposition of lipids, sterols, nutrients, and xenobiotics. In order to investigate changes at the transcriptomics level, we utilized an exon array and calculated expression levels to investigate changes in gene expression in the liver, duodenum, jejunum, and ileum of lactating dams when compared against age-matched virgin controls. Results A two-way mixed models ANOVA was applied to detect differentially expressed genes. Significance calls were defined as a p < 0.05 for the overall physiologic state effect (lactation vs. control), and a within tissue pairwise comparison of p < 0.01. The proportion of false positives, an estimate of the ratio of false positives in the list of differentially expressed genes, was calculated for each tissue. The number of differentially expressed genes was 420 in the liver, 337 in the duodenum, 402 in the jejunum, and 523 in the ileum. The list of differentially expressed genes was in turn analyzed by Ingenuity Pathways Analysis (IPA) to detect biological pathways that were overrepresented. In all tissues, sterol regulatory element binding protein (Srebp)-regulated genes involved in cholesterol synthesis showed increased mRNA expression, with the fewest changes detected in the jejunum. We detected increased Scap mRNA in the liver only, suggesting an explanation for the difference in response to lactation between the liver and small intestine. Expression of Cyp7a1, which catalyzes the rate limiting step in the bile acid biosynthetic pathway, was also significantly increased in liver. In

  1. Training understanding of reversible sentences: a study comparing language-impaired children with age-matched and grammar-matched controls.

    PubMed

    Hsu, Hsinjen Julie; Bishop, Dorothy V M

    2014-01-01

    Introduction. Many children with specific language impairment (SLI) have problems with language comprehension, and little is known about how to remediate these. We focused here on errors in interpreting sentences such as "the ball is above the cup", where the spatial configuration depends on word order. We asked whether comprehension of such short reversible sentences could be improved by computerized training, and whether learning by children with SLI resembled that of younger, typically-developing children. Methods. We trained 28 children with SLI aged 6-11 years, 28 typically-developing children aged from 4 to 7 years who were matched to the SLI group for raw scores on a test of receptive grammar, and 20 typically-developing children who were matched to the SLI group on chronological age. A further 20 children with SLI were given pre- and post-test assessments, but did not undergo training. Those in the trained groups were given training on four days using a computer game adopting an errorless learning procedure, during which they had to select pictures to correspond to spoken sentences such as "the cup is above the drum" or "the bird is below the hat". Half the trained children heard sentences using above/below and the other half heard sentences using before/after (with a spatial interpretation). A total of 96 sentences was presented over four sessions. Half the sentences were unique, whereas the remainder consisted of 12 repetitions of each of four sentences that became increasingly familiar as training proceeded. Results. Age-matched control children performed near ceiling (≥ 90% correct) in the first session and were excluded from the analysis. Around half the trained SLI children also performed this well. Training effects were examined in 15 SLI and 16 grammar-matched children who scored less than 90% correct on the initial training session. Overall, children's scores improved with training. Memory span was a significant predictor of improvement, even

  2. A comparative autoradiography study in post mortem whole hemisphere human brain slices taken from Alzheimer patients and age-matched controls using two radiolabelled DAA1106 analogues with high affinity to the peripheral benzodiazepine receptor (PBR) system.

    PubMed

    Gulyás, Balázs; Makkai, Boglárka; Kása, Péter; Gulya, Károly; Bakota, Lidia; Várszegi, Szilvia; Beliczai, Zsuzsa; Andersson, Jan; Csiba, László; Thiele, Andrea; Dyrks, Thomas; Suhara, Tetsua; Suzuki, Kazutoshi; Higuchi, Makato; Halldin, Christer

    2009-01-01

    The binding of two radiolabelled analogues (N-(5-[125I]Iodo-2-phenoxyphenyl)-N-(2,5-dimethoxybenzyl)acetamide ([125I]desfluoro-DAA1106) and N-(5-[125I]Fluoro-2-phenoxyphenyl)-N-(2-[125I]Iodo-5-methoxybenzyl)acetamide ([125I]desmethoxy-DAA1106) of the peripheral benzodiazepine receptor (PBR) (or TSPO, 18kDa translocator protein) ligand DAA1106 was examined by in vitro autoradiography on human post mortem whole hemisphere brain slices obtained from Alzheimer's disease (AD) patients and age-matched controls. Both [(125)I]desfluoro-IDAA1106 and [(125)I]desmethoxy-IDAA1106 were effectively binding to various brain structures. The binding could be blocked by the unlabelled ligand as well as by other PBR specific ligands. With both radiolabelled compounds, the binding showed regional inhomogeneity and the specific binding values proved to be the highest in the hippocampus, temporal and parietal cortex, the basal ganglia and thalamus in the AD brains. Compared with age-matched control brains, specific binding in several brain structures (temporal and parietal lobes, thalamus and white matter) in Alzheimer brains was significantly higher, indicating that the radioligands can effectively label-activated microglia and the up-regulated PBR/TSPO system in AD. Complementary immunohistochemical studies demonstrated reactive microglia activation in the AD brain tissue and indicated that increased ligand binding coincides with increased regional microglia activation due to neuroinflammation. These investigations yield further support to the PBR/TSPO binding capacity of DAA1106 in human brain tissue, demonstrate the effective usefulness of its radio-iodinated analogues as imaging biomarkers in post mortem human studies, and indicate that its radiolabelled analogues, labelled with short half-time bioisotopes, can serve as prospective in vivo imaging biomarkers of activated microglia and the up-regulated PBR/TSPO system in the human brain.

  3. A comparative autoradiography study in post mortem whole hemisphere human brain slices taken from Alzheimer patients and age-matched controls using two radiolabelled DAA1106 analogues with high affinity to the peripheral benzodiazepine receptor (PBR) system.

    PubMed

    Gulyás, Balázs; Makkai, Boglárka; Kása, Péter; Gulya, Károly; Bakota, Lidia; Várszegi, Szilvia; Beliczai, Zsuzsa; Andersson, Jan; Csiba, László; Thiele, Andrea; Dyrks, Thomas; Suhara, Tetsua; Suzuki, Kazutoshi; Higuchi, Makato; Halldin, Christer

    2009-01-01

    The binding of two radiolabelled analogues (N-(5-[125I]Iodo-2-phenoxyphenyl)-N-(2,5-dimethoxybenzyl)acetamide ([125I]desfluoro-DAA1106) and N-(5-[125I]Fluoro-2-phenoxyphenyl)-N-(2-[125I]Iodo-5-methoxybenzyl)acetamide ([125I]desmethoxy-DAA1106) of the peripheral benzodiazepine receptor (PBR) (or TSPO, 18kDa translocator protein) ligand DAA1106 was examined by in vitro autoradiography on human post mortem whole hemisphere brain slices obtained from Alzheimer's disease (AD) patients and age-matched controls. Both [(125)I]desfluoro-IDAA1106 and [(125)I]desmethoxy-IDAA1106 were effectively binding to various brain structures. The binding could be blocked by the unlabelled ligand as well as by other PBR specific ligands. With both radiolabelled compounds, the binding showed regional inhomogeneity and the specific binding values proved to be the highest in the hippocampus, temporal and parietal cortex, the basal ganglia and thalamus in the AD brains. Compared with age-matched control brains, specific binding in several brain structures (temporal and parietal lobes, thalamus and white matter) in Alzheimer brains was significantly higher, indicating that the radioligands can effectively label-activated microglia and the up-regulated PBR/TSPO system in AD. Complementary immunohistochemical studies demonstrated reactive microglia activation in the AD brain tissue and indicated that increased ligand binding coincides with increased regional microglia activation due to neuroinflammation. These investigations yield further support to the PBR/TSPO binding capacity of DAA1106 in human brain tissue, demonstrate the effective usefulness of its radio-iodinated analogues as imaging biomarkers in post mortem human studies, and indicate that its radiolabelled analogues, labelled with short half-time bioisotopes, can serve as prospective in vivo imaging biomarkers of activated microglia and the up-regulated PBR/TSPO system in the human brain. PMID:18984021

  4. Cairo: repackaging population control.

    PubMed

    Simons, H

    1995-01-01

    Aid agencies, charities, and other nongovernmental organizations once denounced population control programs as racist interference in the third world. Yet, at the United Nations Conference on Population and Development in Cairo last September, these same organizations endorsed very similar ideas. The U.N. can now claim that even its fiercest critics not only have muted their criticism of population control programs but now positively endorse them. Over the last 30 years, population control has been consciously repackaged by the U.S. establishment. The image of population control has changed from being overtly anti-third world to being about giving the people of the third world--especially women--basic rights in family planning. Wrapped up in the language of women's empowerment and environmentalism, the establishment's old arguments about there being too many nonwhite babies in the world, have, unfortunately, won the day. PMID:7591381

  5. Cairo: repackaging population control.

    PubMed

    Simons, H

    1995-01-01

    Aid agencies, charities, and other nongovernmental organizations once denounced population control programs as racist interference in the third world. Yet, at the United Nations Conference on Population and Development in Cairo last September, these same organizations endorsed very similar ideas. The U.N. can now claim that even its fiercest critics not only have muted their criticism of population control programs but now positively endorse them. Over the last 30 years, population control has been consciously repackaged by the U.S. establishment. The image of population control has changed from being overtly anti-third world to being about giving the people of the third world--especially women--basic rights in family planning. Wrapped up in the language of women's empowerment and environmentalism, the establishment's old arguments about there being too many nonwhite babies in the world, have, unfortunately, won the day.

  6. Soluble BACE-1 Activity and sAβPPβ Concentrations in Alzheimer's Disease and Age-Matched Healthy Control Cerebrospinal Fluid from the Alzheimer's Disease Neuroimaging Initiative-1 Baseline Cohort.

    PubMed

    Savage, Mary J; Holder, Daniel J; Wu, Guoxin; Kaplow, June; Siuciak, Judith A; Potter, William Z

    2015-01-01

    β-site amyloid precursor protein-cleaving enzyme 1 (BACE1) plays an important role in the development of Alzheimer's disease (AD), freeing the amyloid-β (Aβ) N-terminus from the amyloid-β protein precursor (AβPP), the first step in Aβ formation. Increased BACE1 activity in AD brain or cerebrospinal fluid (CSF) has been reported. Other studies, however, found either no change or a decrease with AD diagnosis in either BACE1 activity or sAβPPβ, the N-terminal secreted product of BACE1 (sBACE1) activity on AβPP. Here, sBACE1 enzymatic activity and secreted AβPPβ (sAβPPβ) were measured in Alzheimer's Disease Neuroimaging Initiative-1 (ADNI-1) baseline CSF samples and no statistically significant changes were found in either measure comparing healthy control, mild cognitively impaired, or AD individual samples. While CSF sBACE1 activity and sAβPPβ demonstrated a moderate yet significant degree of correlation with each other, there was no correlation of either analyte to CSF Aβ peptide ending at residue 42. Surprisingly, a stronger correlation was demonstrated between CSF sBACE1 activity and tau, which was comparable to that between CSF Aβ₄₂ and tau. Unlike for these latter two analytes, receiver-operator characteristic curves demonstrate that neither CSF sBACE1 activity nor sAβPPβ concentrations can be used to differentiate between healthy elderly and AD individuals.

  7. Soluble BACE-1 Activity and sAβPPβ Concentrations in Alzheimer's Disease and Age-Matched Healthy Control Cerebrospinal Fluid from the Alzheimer's Disease Neuroimaging Initiative-1 Baseline Cohort.

    PubMed

    Savage, Mary J; Holder, Daniel J; Wu, Guoxin; Kaplow, June; Siuciak, Judith A; Potter, William Z

    2015-01-01

    β-site amyloid precursor protein-cleaving enzyme 1 (BACE1) plays an important role in the development of Alzheimer's disease (AD), freeing the amyloid-β (Aβ) N-terminus from the amyloid-β protein precursor (AβPP), the first step in Aβ formation. Increased BACE1 activity in AD brain or cerebrospinal fluid (CSF) has been reported. Other studies, however, found either no change or a decrease with AD diagnosis in either BACE1 activity or sAβPPβ, the N-terminal secreted product of BACE1 (sBACE1) activity on AβPP. Here, sBACE1 enzymatic activity and secreted AβPPβ (sAβPPβ) were measured in Alzheimer's Disease Neuroimaging Initiative-1 (ADNI-1) baseline CSF samples and no statistically significant changes were found in either measure comparing healthy control, mild cognitively impaired, or AD individual samples. While CSF sBACE1 activity and sAβPPβ demonstrated a moderate yet significant degree of correlation with each other, there was no correlation of either analyte to CSF Aβ peptide ending at residue 42. Surprisingly, a stronger correlation was demonstrated between CSF sBACE1 activity and tau, which was comparable to that between CSF Aβ₄₂ and tau. Unlike for these latter two analytes, receiver-operator characteristic curves demonstrate that neither CSF sBACE1 activity nor sAβPPβ concentrations can be used to differentiate between healthy elderly and AD individuals. PMID:25790831

  8. Repackaging population control.

    PubMed

    Simons, H

    1994-01-01

    "While the abortion controversy captured the world's headlines, the real significance of the UN's [1994 International Conference on Population and Development] went largely unnoticed.... After decades of failure, the UN has finally pushed the issue of population control center stage by repackaging it in a blurry concern for the rights of women." The author argues that the conference's strategy was to target women as both the cause of overpopulation and the locus of the problem's solution.

  9. Controlling Population with Pollution

    ERIC Educational Resources Information Center

    Browne, Joseph

    2010-01-01

    Population models are often discussed in algebra, calculus, and differential equations courses. In this article we will use the human population of the world as our application. After quick looks at two common models we'll investigate more deeply a model which incorporates the negative effect that accumulated pollution may have on population.

  10. Approach to population control.

    PubMed

    Bose, A

    1983-01-26

    Due to the fact that India was the 1st nation to adopt population control as a state policy and that targets for various family planning methods are set by the Department of Family Planning, it is assumed that family planning is basically the concern of the Department of Family Planning. Consequently, family planning is viewed as a public sector activity that requires little participation on the part of the people. This presents a great danger to the success of the family planning program. Family planning needs to be the primary concern of the people and not the government. The new 20 point program emphasizes that family planning should be promoted on a voluntary basis as a people's movement. This has been interpreted by many to mean that increasingly more funds should be given to voluntary agencies working in the field of family planning. Yet, there is deep distrust on the part of the government departments regarding doling out funds to voluntary agencies. It is suggested that the government should adopt a new approach to the problem of population control through the promotion and mobilization of voluntary effort in rural areas. In view of the clear demonstration of the impact of female education on fertility levels, the Family Planning Department should announce a new scheme to help all voluntary agencies which focus attention on the education of girls in neglected rural areas and should launch a special schooling program for girls in the area of nutrition. In addition, the informal education of women through the mobilization of local talent and resources to generate social awareness should be undertaken. In India, Kerala has the distinction of having the highest literacy rate, the highest life expectancy, the lowest mortality and infant mortality rates, and the lowest birthrate. The birthrate in rural Kerala is 27/1000 in contrast to 40/1000 in rural Uttar Pradesh. A high average marriage age has contributed substantially to lowering the birthrate. The key

  11. Population control in symbiotic corals

    SciTech Connect

    Falkowski, P.G. ); Dubinsky, Z. ); Muscatine, L. ); McCloskey, L. )

    1993-10-01

    Stability in symbiotic association requires control of population growth between symbionts. The population density of zooxanthellae per unit surface area of most symbiotic corals is remarkably consistant. How is the population density of zooxanthellae maintained and what happens to the symbiotic association if the balance between algae and host is perturbed. The answers to these question, examined in this paper, provide a framework for understanding how the size of the component populations is controlled in symbiotic associations. The topic areas covered include the following: carbon economy in a symbiotic coral; effects of nutrient enrichment; the chemostat model of population control; the effects of exposure to ammonium levels. Ammonium ions and organic materials are the factors which maintain the density of zooxanthellae. 32 refs., 5 figs.

  12. [Population control and environment protection].

    PubMed

    Qu, G

    1982-01-29

    Although many factors cause environmental pollution and damage, the most important and basic factor is a rapidly increasing population. Therefore, a balanced development of population and environment is essential. The pressure a rapidly increasing populaton exerts on the environment has many aspects. The pressure of population on land resources results in increased land use and increased insecticide use due to increased insect tolerance leading to decreased productivity of cultivated land, increased desert formation, and decreased food supply. Population pressure on forest resources leads to land erosion; one of the major causes of the 1981 flood in Sichuan was attributed to excessive logging activities. Demand for fuels (firewood, straws, animal manures) by an increasing population leads to decrease in natural fertilizers, decreased food production, and energy shortage in rural areas. Population pressure on cities leads to air, water, noise and other environmental pollution as well as decrease in housing facilities and in green vegetation. Problems resulting from population pressures on industrial development include industrial and environmental pollution and unemployment. Population increases and accompanying industrial activities affect the weather which in turn affects the quality of agriculture, forests, and lakes. Thus, if unchecked, atmospheric carbon dioxide level would double by the middle of the next century, which would lead to increase in atmospheric temperature with disastrous consequences. Therefore, a well planned program for population control is essential for achieving decent quality of life.

  13. Electrophysiological Neuroimaging using sLORETA Comparing 22 Age Matched Male and Female Schizophrenia Patients

    PubMed Central

    Eugene, Andy R.; Masiak, Jolanta; Kapica, Jacek; Masiak, Marek

    2015-01-01

    Introduction The purpose of this electrophysiological neuroimaging study was to provide a deeper mechanistic understanding of both olanzapine and risperidone pharmacodynamics relative to gender. In doing so, we age-matched 22 men and women and evaluated their resting-state EEG recordings and later used standard low resolution brain Electrotomography to visualize the differences in brain activity amongst the two patient groups. Methods In this investigation, electroencephalogram (EEG) data were analyzed from male and female schizophrenia patients treated with either olanzapine or risperidone, both atypical antipsychotics, during their in-patient stay at the Department of Psychiatry. Twenty-two males and females were age-matched and EEG recordings were analyzed from 19 Ag/AgCl electrodes. Thirty-seconds of resting EEG were spectrally transformed in standardized low resolution electromagnetic tomography (sLORETA). 3D statistical non-paramentric maps for the sLORETA Global Field Power within each band were finally computed. Results The results indicated that, relative to males patients, females schizophrenia patients had increased neuronal synchronization in delta frequency, slow-wave, EEG band located in the dorsolateral prefrontal cortex, within the middle frontal gyrus (t= -2.881, p < 0.03580). These findings suggest that females experience greater dopamine (D2) receptor and serotonin (5-HT2) receptor neuronal blockade relative to age-matched males. Further, our finding provided insight to the pharmacodynamics of second-generation antipsychotics olanzapine and risperidone. Conclusion When compared to male patients, female patients, suffering from schizophrenia, have D2 and 5-HT2 receptors that are blocked more readily than age-matched male schizophrenia patients. Clinically, this may translate into a quicker time to treatment-response in females as compared to male patients. PMID:26617679

  14. Electrical stimulation directs engineered cardiac tissue to an age-matched native phenotype

    PubMed Central

    Lasher, Richard A; Pahnke, Aric Q; Johnson, Jeffrey M; Sachse, Frank B

    2012-01-01

    Quantifying structural features of native myocardium in engineered tissue is essential for creating functional tissue that can serve as a surrogate for in vitro testing or the eventual replacement of diseased or injured myocardium. We applied three-dimensional confocal imaging and image analysis to quantitatively describe the features of native and engineered cardiac tissue. Quantitative analysis methods were developed and applied to test the hypothesis that environmental cues direct engineered tissue toward a phenotype resembling that of age-matched native myocardium. The analytical approach was applied to engineered cardiac tissue with and without the application of electrical stimulation as well as to age-matched and adult native tissue. Individual myocytes were segmented from confocal image stacks and assigned a coordinate system from which measures of cell geometry and connexin-43 spatial distribution were calculated. The data were collected from 9 nonstimulated and 12 electrically stimulated engineered tissue constructs and 5 postnatal day 12 and 7 adult hearts. The myocyte volume fraction was nearly double in stimulated engineered tissue compared to nonstimulated engineered tissue (0.34 ± 0.14 vs 0.18 ± 0.06) but less than half of the native postnatal day 12 (0.90 ± 0.06) and adult (0.91 ± 0.04) myocardium. The myocytes under electrical stimulation were more elongated compared to nonstimulated myocytes and exhibited similar lengths, widths, and heights as in age-matched myocardium. Furthermore, the percentage of connexin-43-positive membrane staining was similar in the electrically stimulated, postnatal day 12, and adult myocytes, whereas it was significantly lower in the nonstimulated myocytes. Connexin-43 was found to be primarily located at cell ends for adult myocytes and irregularly but densely clustered over the membranes of nonstimulated, stimulated, and postnatal day 12 myocytes. These findings support our hypothesis and reveal that the

  15. Comparison of serum sodium and potassium levels in patients with senile cataract and age-matched individuals without cataract

    PubMed Central

    Mathur, Gaurav; Pai, Vijaya

    2016-01-01

    Aim: The study was to analyze mean serum sodium and potassium levels in cataract patients and age-matched individuals without cataract. Methods and Materials: It was a prospective case-control study. Individuals more than 50 years of age who attended our ophthalmic center in the year 2007-2010 were grouped into those having cataract and those without cataract. Mean serum sodium and potassium levels in the cataract groups were calculated and compared with the control group. Statistical software SPSS14 was used for statistical analysis. Results: Mean serum sodium levels in cataract group was 135.1 meqv/l and 133 meqv/l in the control group. Mean potassium was 3.96 meqv/l in the case study group and 3.97 meqv/l in controls. Mean sodium levels among cases were significantly higher than control group. No difference was seen in the PSC group and control. The difference in mean potassium among the two groups was statistically insignificant. Conclusion: Diets with high sodium contents are a risk factor for senile cataract formation and dietary modifications can possibly reduce the rate of progression cataract. PMID:23552357

  16. Outlining a Population "at Risk" of Parkinson's Disease: Evidence from a Case-Control Study.

    PubMed

    Schirinzi, Tommaso; Martella, Giuseppina; D'Elia, Alessio; Di Lazzaro, Giulia; Imbriani, Paola; Madeo, Graziella; Monaco, Leonardo; Maltese, Marta; Pisani, Antonio

    2016-01-01

    The multifactorial pathogenesis of Parkinson's Disease (PD) requires a careful identification of populations "at risk" of developing the disease. In this case-control study we analyzed a large Italian population, in an attempt to outline general criteria to define a population "at risk" of PD. We enrolled 300 PD patients and 300 controls, gender and age matched, from the same urban geographical area. All subjects were interviewed on demographics, family history of PD, occupational and environmental toxicants exposure, smoking status, and alcohol consumption. A sample of 65 patients and 65 controls also underwent serum dosing of iron, copper, mercury, and manganese by means of Inductively Coupled-Plasma-Mass-Spectrometry (ICP-MS). Positive family history, toxicants exposure, non-current-smoker, and alcohol nonconsumer status occurred as significant risk factors in our population. The number of concurring risk factors overlapping in the same subject impressively increased the overall risk. No significant differences were measured in the metal serum levels. Our findings indicate that combination of three to four concurrent PD-risk factors defines a condition "at risk" of PD. A simple stratification, based on these questionnaires, might be of help in identifying subjects suitable for neuroprotective strategies. PMID:27651975

  17. Outlining a Population "at Risk" of Parkinson's Disease: Evidence from a Case-Control Study.

    PubMed

    Schirinzi, Tommaso; Martella, Giuseppina; D'Elia, Alessio; Di Lazzaro, Giulia; Imbriani, Paola; Madeo, Graziella; Monaco, Leonardo; Maltese, Marta; Pisani, Antonio

    2016-01-01

    The multifactorial pathogenesis of Parkinson's Disease (PD) requires a careful identification of populations "at risk" of developing the disease. In this case-control study we analyzed a large Italian population, in an attempt to outline general criteria to define a population "at risk" of PD. We enrolled 300 PD patients and 300 controls, gender and age matched, from the same urban geographical area. All subjects were interviewed on demographics, family history of PD, occupational and environmental toxicants exposure, smoking status, and alcohol consumption. A sample of 65 patients and 65 controls also underwent serum dosing of iron, copper, mercury, and manganese by means of Inductively Coupled-Plasma-Mass-Spectrometry (ICP-MS). Positive family history, toxicants exposure, non-current-smoker, and alcohol nonconsumer status occurred as significant risk factors in our population. The number of concurring risk factors overlapping in the same subject impressively increased the overall risk. No significant differences were measured in the metal serum levels. Our findings indicate that combination of three to four concurrent PD-risk factors defines a condition "at risk" of PD. A simple stratification, based on these questionnaires, might be of help in identifying subjects suitable for neuroprotective strategies.

  18. Neural mechanisms of verb argument structure processing in agrammatic aphasic and healthy age-matched listeners

    PubMed Central

    Thompson, C.K.; Bonakdarpour, B.; Fix, S.F.

    2010-01-01

    Processing of lexical verbs involves automatic access to argument structure entries entailed within the verb's representation. Recent neuroimaging studies with young normal listeners suggest that this involves bilateral posterior perisylvian tissue, with graded activation in these regions based on argument structure complexity. The aim of the present study was to examine the neural mechanisms of verb processing using functional magnetic resonance imaging (fMRI) in older normal volunteers and patients with stroke-induced agrammatic aphasia, a syndrome in which verb, as compared to noun, production often is selectively impaired, but verb comprehension in both on-line and off-line tasks is spared. Fourteen healthy listeners and five age-matched aphasic patients performed a lexical decision task, which examined verb processing by argument structure complexity, i.e., one-argument (i.e., intransitive (v1)); two-argument (i.e., transitive (v2)), and three-argument (v3) verbs. Results for the age-matched listeners largely replicated those for younger participants studied by Thompson et al. (2007): v3-v1 comparisons showed activation of the angular gyrus in both hemispheres and this same heteromodal region was activated in the left hemisphere in the (v2+v3)-v1 contrast. Similar results were derived for the agrammatic aphasic patients, however, activation was unilateral (in the right hemisphere for 3 participants) rather than bilateral likely because these patients' lesions extended to the left temporoparietal region. All performed the task with high accuracy and, despite differences in lesion site and extent, they recruited spared tissue in the same regions as healthy normals. Consistent with psycholinguistic models of sentence processing, these findings indicate that the posterior language network is engaged for processing verb argument structure and is crucial for semantic integration of argument structure information. PMID:19702460

  19. Refugees, immigrants aggravate population controls.

    PubMed

    Struck, D

    1994-09-01

    The UN Conference on Population and Development in Cairo in 1994 will discuss the pressure of population growth, the increase in the numbers of refugees, and labor migration between developing and developed countries. Population movement has been estimated as 1/50 in the world, regardless of reason. The impact of movement can be to augment a declining work force or to strain resources in poor countries, such as Zaire or Thailand. Rich countries may also respond with resentment and political turmoil, as is currently occurring in Germany. The tendency is to respond after the fact. Rwanda could be used as an example of a country with population pressure on land resources, which has exacerbated ethnic conflict. If the world in 1994 shows this pattern, the concern is that the future prospects are likely to reflect even greater turmoil and migration. The number of refugees has already increased from 2.5 million in 1970 to 20 million today. The head of the UN Commission on Refugees views the end of the Cold War as responsible for exposed and heightened ethnic and tribal rivalry. Migration movement is viewed as the desire for an improvement in quality of life. Significant shifts are to developed countries such as the US, Canada, Australia, and New Zealand. The 1994 UN Plan of Action offers concrete recommendations about mass movements. Recommendations are made to assure host country's assurances of protection in work and safety for migrants, removal of restrictive banking practices that impede monetary transfers between countries, and arrangements for temporary migration. Host countries are urged to provide assistance for return migration. Rights and equal treatment with nationals should be extended to longterm migrants. Each country has a right to enact migration restrictions. Smuggling of immigrants should be stopped through international cooperation. Countries of origin have a responsibility to readmit nationals rejected by other countries. There are few recommendations

  20. Optimal control of gypsy moth populations.

    PubMed

    Whittle, Andrew; Lenhart, Suzanne; White, K A J

    2008-02-01

    This study investigates an optimal strategy for the cost effective control of gypsy moth populations. Gypsy moth populations cycle between low sparse numbers to high outbreak levels and it is during the outbreak levels that the moths cause extensive damage to plant foliage which can lead to deforestation. Deforestation can result in significant economic damage to infested areas, and consequently, there have been many efforts to control moth populations. One effective method of control is the use of the biocontrol agent, Gypchek, but its production is costly. We develop a mathematical model which combines population dynamics and optimal control of the moth population to explore strategies by which the total cost of the gypsy moth problem (economic damage and cost of Gypchek) can be minimized.

  1. Optimal birth control of population dynamics.

    PubMed

    Chan, W L; Guo, B Z

    1989-11-01

    The authors studied optimal birth control policies for an age-structured population of McKendrick type which is a distributed parameter system involving 1st order partial differential equations with nonlocal bilinear boundary control. The functional analytic approach of Dubovitskii and Milyutin is adopted in the investigation. Maximum principles for problems with a free end condition and fixed final horizon are developed, and the time optimal control problems, the problem with target sets, and infinite planning horizon case are investigated.

  2. Reproductive rights and population control in Zimbabwe.

    PubMed

    Mcfadden, P

    1995-05-01

    The author argues that population control in Zimbabwe, in other developing countries, and even in developed countries is targeted at non-whites and at the poorer classes. She discusses fertility vaccines and male sterilization in this context, and makes the point that while the technology of population control flows from the North to the South, resources from the South are flowing North to maintain the economic status quo. "I think that the real population problem is the widening gap between a few greedy, irresponsible people, most of whom happen to be located in the North, and the rest of humankind, whose lives have been so denigrated that they are now merely statistics.... We can easily see that what should be feeding, clothing, housing, healing, pleasing Africans, goes North, all in the name of ¿development'."

  3. Outlining a Population “at Risk” of Parkinson's Disease: Evidence from a Case-Control Study

    PubMed Central

    Schirinzi, Tommaso; Martella, Giuseppina; D'Elia, Alessio; Di Lazzaro, Giulia; Imbriani, Paola; Madeo, Graziella; Monaco, Leonardo; Maltese, Marta

    2016-01-01

    The multifactorial pathogenesis of Parkinson's Disease (PD) requires a careful identification of populations “at risk” of developing the disease. In this case-control study we analyzed a large Italian population, in an attempt to outline general criteria to define a population “at risk” of PD. We enrolled 300 PD patients and 300 controls, gender and age matched, from the same urban geographical area. All subjects were interviewed on demographics, family history of PD, occupational and environmental toxicants exposure, smoking status, and alcohol consumption. A sample of 65 patients and 65 controls also underwent serum dosing of iron, copper, mercury, and manganese by means of Inductively Coupled-Plasma-Mass-Spectrometry (ICP-MS). Positive family history, toxicants exposure, non-current-smoker, and alcohol nonconsumer status occurred as significant risk factors in our population. The number of concurring risk factors overlapping in the same subject impressively increased the overall risk. No significant differences were measured in the metal serum levels. Our findings indicate that combination of three to four concurrent PD-risk factors defines a condition “at risk” of PD. A simple stratification, based on these questionnaires, might be of help in identifying subjects suitable for neuroprotective strategies.

  4. Outlining a Population “at Risk” of Parkinson's Disease: Evidence from a Case-Control Study

    PubMed Central

    Schirinzi, Tommaso; Martella, Giuseppina; D'Elia, Alessio; Di Lazzaro, Giulia; Imbriani, Paola; Madeo, Graziella; Monaco, Leonardo; Maltese, Marta

    2016-01-01

    The multifactorial pathogenesis of Parkinson's Disease (PD) requires a careful identification of populations “at risk” of developing the disease. In this case-control study we analyzed a large Italian population, in an attempt to outline general criteria to define a population “at risk” of PD. We enrolled 300 PD patients and 300 controls, gender and age matched, from the same urban geographical area. All subjects were interviewed on demographics, family history of PD, occupational and environmental toxicants exposure, smoking status, and alcohol consumption. A sample of 65 patients and 65 controls also underwent serum dosing of iron, copper, mercury, and manganese by means of Inductively Coupled-Plasma-Mass-Spectrometry (ICP-MS). Positive family history, toxicants exposure, non-current-smoker, and alcohol nonconsumer status occurred as significant risk factors in our population. The number of concurring risk factors overlapping in the same subject impressively increased the overall risk. No significant differences were measured in the metal serum levels. Our findings indicate that combination of three to four concurrent PD-risk factors defines a condition “at risk” of PD. A simple stratification, based on these questionnaires, might be of help in identifying subjects suitable for neuroprotective strategies. PMID:27651975

  5. Which oropharyngeal factors are significant risk factors for obstructive sleep apnea? An age-matched study and dentist perspectives

    PubMed Central

    Ruangsri, Supanigar; Jorns, Teekayu Plangkoon; Puasiri, Subin; Luecha, Thitisan; Chaithap, Chariya; Sawanyawisuth, Kittisak

    2016-01-01

    Objective Obstructive sleep apnea (OSA) is a common sleep breathing disorder. Untreated OSA may lead to a number of cardiovascular complications. Dentists may play an important role in OSA detection by conducting careful oral examinations. This study focused on the correlation of oral anatomical features in Thai patients who presented with OSA. Methods We conducted a prospective comparative study at a sleep/hypertension clinic and a dental clinic at Khon Kaen University in Thailand. Patients with OSA were enrolled in the study, along with age-matched patients with non-OSA (controls). Baseline characteristics, clinical data, and oropharyngeal data of all patients were compared between the two groups. Oropharyngeal measurements included tongue size, torus mandibularis, Mallampati classification, palatal space, and lateral pharyngeal wall area. Multivariate logistic regression analysis was used to identify the factors associated with OSA. Results During the study period, there were 156 patients who met the study criteria; 78 were patients with OSA and the other 78 were healthy control subjects. In the OSA group, there were 43 males with a mean age of 53 (standard deviation 12.29) years and a mean BMI of 30.86 kg/mm2. There were 37 males in the control group with a mean age of 50 (standard deviation 12.04) years and a mean BMI of 24.03 kg/mm2. According to multivariate logistic analysis, three factors were perfectly associated with OSA, including torus mandibularis class 6, narrow lateral pharyngeal wall, and Mallampati class 4. There were two other significant factors associated with having OSA, namely, BMI and Mallampati classification. The adjusted odds ratios (95% confidence interval) of these two factors were 1.445 (1.017, 2.052) and 5.040 (1.655, 15.358), respectively. Conclusion Dentists may play an important role in the detection of OSA in patients with high BMI through careful oropharyngeal examination in routine dental treatment. A large torus mandibularis

  6. Solvent exposure and malignant lymphoma: a population-based case-control study in Germany

    PubMed Central

    Seidler, Andreas; Möhner, Matthias; Berger, Jürgen; Mester, Birte; Deeg, Evelin; Elsner, Gine; Nieters, Alexandra; Becker, Nikolaus

    2007-01-01

    Aims To analyze the relationship between exposure to chlorinated and aromatic organic solvents and malignant lymphoma in a multi-centre, population-based case-control study. Methods Male and female patients with malignant lymphoma (n = 710) between 18 and 80 years of age were prospectively recruited in six study regions in Germany (Ludwigshafen/Upper Palatinate, Heidelberg/Rhine-Neckar-County, Würzburg/Lower Frankonia, Hamburg, Bielefeld/Gütersloh, and Munich). For each newly recruited lymphoma case, a gender, region and age-matched (± 1 year of birth) population control was drawn from the population registers. In a structured personal interview, we elicited a complete occupational history, including every occupational period that lasted at least one year. On the basis of job task-specific supplementary questionnaires, a trained occupational physician assessed the exposure to chlorinated hydrocarbons (trichloroethylene, tetrachloroethylene, dichloromethane, carbon tetrachloride) and aromatic hydrocarbons (benzene, toluene, xylene, styrene). Odds ratios (OR) and 95% confidence intervals (CI) were calculated using conditional logistic regression analysis, adjusted for smoking (in pack years) and alcohol consumption. To increase the statistical power, patients with specific lymphoma subentities were additionally compared with the entire control group using unconditional logistic regression analysis. Results We observed a statistically significant association between high exposure to chlorinated hydrocarbons and malignant lymphoma (Odds ratio = 2.1; 95% confidence interval 1.1–4.3). In the analysis of lymphoma subentities, a pronounced risk elevation was found for follicular lymphoma and marginal zone lymphoma. When specific substances were considered, the association between trichloroethylene and malignant lymphoma was of borderline statistical significance. Aromatic hydrocarbons were not significantly associated with the lymphoma diagnosis. Conclusion In

  7. Birth control, population control, and family planning: an overview.

    PubMed

    Critchlow, D T

    1995-01-01

    This overview of the US birth control movement reflects on the emergence of family planning policy due to the efforts of Margaret Sanger, feminists, and the civil rights movement, the eugenics motive to limit "deviant" populations, and the population control movement, which aims to solve social and economic problems through fertility control. Population control moved through three stages: from the cause of "voluntary motherhood" to advance suffrage and women's political and social status, to the concept of "birth control" promoted by socialist feminists to help empower women and the working class, to, from 1920 on, a liberal movement for civil rights and population control. Physicians such as Dr. Robert Latou Dickinson legitimized the movement in the formation of the Committee on Maternal Health in 1925, but the movement remained divided until 1939, when Sanger's group merged with the American Birth Control League, the predecessor of the present Planned Parenthood Federation of America. A key legal decision in 1939 in the United States v. One Package amended the Comstock Act and allowed for the distribution of birth control devices by mail to physicians. Sanger, after a brief retirement, formed the International Planned Parenthood Federation and supported research into the pill. Eugenicists through the Committee on Maternal Health supported Christopher Tietze and others developing the pill. Final constitutional access to contraception based on the right to privacy was granted in Griswold v. Connecticut. The ruling in Eisenstadt v. Baird in 1972 extended this right to unmarried persons. The right to privacy was further extended in the Roe v. Wade decision in 1973 on legal abortion. The argument for improving the quality of the population remained from the formation of the Population Reference Bureau in 1929 through the 1960s. Under the leadership of Rockefeller, population control was defined as justified on a scientific and humanitarian basis. US government support

  8. Birth control, population control, and family planning: an overview.

    PubMed

    Critchlow, D T

    1995-01-01

    This overview of the US birth control movement reflects on the emergence of family planning policy due to the efforts of Margaret Sanger, feminists, and the civil rights movement, the eugenics motive to limit "deviant" populations, and the population control movement, which aims to solve social and economic problems through fertility control. Population control moved through three stages: from the cause of "voluntary motherhood" to advance suffrage and women's political and social status, to the concept of "birth control" promoted by socialist feminists to help empower women and the working class, to, from 1920 on, a liberal movement for civil rights and population control. Physicians such as Dr. Robert Latou Dickinson legitimized the movement in the formation of the Committee on Maternal Health in 1925, but the movement remained divided until 1939, when Sanger's group merged with the American Birth Control League, the predecessor of the present Planned Parenthood Federation of America. A key legal decision in 1939 in the United States v. One Package amended the Comstock Act and allowed for the distribution of birth control devices by mail to physicians. Sanger, after a brief retirement, formed the International Planned Parenthood Federation and supported research into the pill. Eugenicists through the Committee on Maternal Health supported Christopher Tietze and others developing the pill. Final constitutional access to contraception based on the right to privacy was granted in Griswold v. Connecticut. The ruling in Eisenstadt v. Baird in 1972 extended this right to unmarried persons. The right to privacy was further extended in the Roe v. Wade decision in 1973 on legal abortion. The argument for improving the quality of the population remained from the formation of the Population Reference Bureau in 1929 through the 1960s. Under the leadership of Rockefeller, population control was defined as justified on a scientific and humanitarian basis. US government support

  9. Occupation and malignant lymphoma: a population based case control study in Germany

    PubMed Central

    Mester, B; Nieters, A; Deeg, E; Elsner, G; Becker, N; Seidler, A

    2006-01-01

    Aims To identify occupations suspected to be associated with malignant lymphoma and to generate new hypotheses about occupational risks in a multicentre, population based case control study. Methods Male and female patients with malignant lymphoma (n = 710) aged 18–80 years of age were prospectively recruited in six study regions in Germany. For each newly recruited lymphoma case, a sex, region, and age matched control was drawn from the population registers. Odds ratios and 95% confidence intervals for major occupations and industries were calculated using conditional logistic regression analysis, adjusted for smoking (in pack‐years) and alcohol consumption. Patients with specific lymphoma subentities were additionally compared with the entire control group using unconditional logistic regression analysis. Results The following economic/industrial sectors were positively associated with lymphoma: food products, beverages, tobacco; paper products, publishing and printing; and metals. Chemicals; real estate, renting, and business activities were negatively associated with lymphoma diagnosis. The authors observed an increased overall lymphoma risk among architects; maids; farmers; glass formers; and construction workers. Shoemaking and leather goods making was negatively associated with the lymphoma diagnosis (although based on small numbers). In the occupational group analysis of lymphoma subentities, Hodgkin's lymphoma was significantly associated only with rubber and plastic products making; diffuse large B cell lymphoma risk was considerably increased among metal processors; follicular lymphoma showed highly significant risk increases for several occupational groups (medical, dental, and veterinary workers; sales workers; machinery fitters; and electrical fitters); and multiple myeloma showed a particularly pronounced risk increase for farmers as well as for agriculture and animal husbandry workers. Conclusions The results partly confirm previously

  10. Evaluation of visual stress symptoms in age-matched dyslexic, Meares-Irlen syndrome and normal adults

    PubMed Central

    Alanazi, Mana A.; Alanazi, Saud A.; Osuagwu, Uchechukwu L.

    2016-01-01

    AIM To examine the prevalence of dyslexia and Meares-Irlen syndrome (MIS) among female students and determine their level of visual stress in comparison with normal subjects. METHODS A random sample of 450 female medical students of King Saud University Riyadh (age range, 18-30y) responded to a wide range of questions designed to accomplish the aims of this study. The detailed questionnaire consisted of 54 questions with 12 questions enquiring on ocular history and demography of participants while 42 questions were on visual symptoms. Items were categorized into critical and non-critical questions (CQ and NCQ) and were rated on four point Likert scale. Based on the responses obtained, the subjects were grouped into normal (control), dyslexic with or without MIS (Group 1) and subjects with MIS only (Group 2). Responses were analysed as averages and mean scores were calculated and compared between groups using one way analysis of variance to evaluate total visual stress score (TVSS=NCQ+CQ), critical and non-critical visual stress scores. The relationship between categorical variables such as age, handedness and condition were assessed with Chi-square test. RESULTS The completion rate was 97.6% and majority of the respondents (92%) were normal readers, 2% dyslexic and 6% had MIS. They were age-matched. More than half of the participants had visited an eye care practitioner in the last 2y. About 13% were recommended eye exercises and one participant experienced pattern glare. Hand preference was not associated with any condition but Group 1 subjects (3/9, 33%) were significantly more likely to be diagnosed of lazy eye than Group 2 (2/27, 7%) and control (27/414, 7%) subjects. The mean±SD of TVSS responses were 63±14 and it was 44±9 for CQ and 19±5 for NCQ. Responses from all three variables were normally distributed but the CQ responses were on the average more positive (82%) in Group 2 and less positive (46%) in Group 1 than control. With NCQ, the responses were

  11. Population ecology and the control of pests

    PubMed Central

    Birch, L. C.

    1963-01-01

    An understanding of the factors responsible for the numbers of animals observed is essential for effective integrated control of pests. An ecological study need not, however, be complete for it to be useful; many incomplete such studies have led to clues that have served as important guides in control programmes. However, it is important that the study of animal numbers be undertaken with a completely general model in mind. Some ecological models suggested are too restricted to be generally applicable. The generalized model proposed by the author is based on the proposition that the chance to survive and multiply depends on environment, which may be effectively studied as having five components: resources, climate, numbers of the same species, numbers of other species, and hazards. Any of these components may be important and different components may be important at different times in the history of an animal population. Populations are most often limited by inaccessibility of resources and by the shortage of time during which the environment is favourable to an increase in numbers. An understanding of these factors suggests ways in which numbers may be further restricted. The student of pest control must determine if such ways can be economically used in a programme of integrated control. PMID:20604164

  12. Population-level control of gene expression

    NASA Astrophysics Data System (ADS)

    Nevozhay, Dmitry; Adams, Rhys; van Itallie, Elizabeth; Bennett, Matthew; Balazsi, Gabor

    2011-03-01

    Gene expression is the process that translates genetic information into proteins, that determine the way cells live, function and even die. It was demonstrated that cells with identical genomes exposed to the same environment can differ in their protein composition and therefore phenotypes. Protein levels can vary between cells due to the stochastic nature of intracellular biochemical events, indicating that the genotype-phenotype connection is not deterministic at the cellular level. We asked whether genomes could encode isogenic cell populations more reliably than single cells. To address this question, we built two gene circuits to control three cell population-level characteristics: gene expression mean, coefficient of variation and non-genetic memory of previous expression states. Indeed, we found that these population-level characteristics were more predictable than the gene expression of single cells in a well-controlled environment. This research was supported by the NIH Director's New Innovator Award 1DP2 OD006481-01 and Welch Foundation Grant C-1729.

  13. Genetic control of mosquitoes: population suppression strategies.

    PubMed

    Wilke, André Barretto Bruno; Marrelli, Mauro Toledo

    2012-01-01

    Over the last two decades, morbidity and mortality from malaria and dengue fever among other pathogens are an increasing Public Health problem. The increase in the geographic distribution of vectors is accompanied by the emergence of viruses and diseases in new areas. There are insufficient specific therapeutic drugs available and there are no reliable vaccines for malaria or dengue, although some progress has been achieved, there is still a long way between its development and actual field use. Most mosquito control measures have failed to achieve their goals, mostly because of the mosquito's great reproductive capacity and genomic flexibility. Chemical control is increasingly restricted due to potential human toxicity, mortality in no target organisms, insecticide resistance, and other environmental impacts. Other strategies for mosquito control are desperately needed. The Sterile Insect Technique (SIT) is a species-specific and environmentally benign method for insect population suppression, it is based on mass rearing, radiation mediated sterilization, and release of a large number of male insects. Releasing of Insects carrying a dominant lethal gene (RIDL) offers a solution to many of the drawbacks of traditional SIT that have limited its application in mosquitoes while maintaining its environmentally friendly and species-specific utility. The self-limiting nature of sterile mosquitoes tends to make the issues related to field use of these somewhat less challenging than for self-spreading systems characteristic of population replacement strategies. They also are closer to field use, so might be appropriate to consider first. The prospect of genetic control methods against mosquito vectored human diseases is rapidly becoming a reality, many decisions will need to be made on a national, regional and international level regarding the biosafety, social, cultural and ethical aspects of the use and deployment of these vector control methods.

  14. Risk factors in facial hyperpigmentation in Maghrebian population - a case-control study.

    PubMed

    Benchikhi, H; Atide, N; Jroundi, I; Humbert, P; Lakhdar, H

    2012-10-01

    Triggering factors seem to be multiple in the pathogenesis of facial hyperpigmentation (FH), as dark skin types, pregnancy, sun exposure… The aim of this study was to investigate the risk factors for FH in Maghrebian population. Patients with FH were included in a case-controlled study. Following data were recorded: age, sex, parity, phototype, FH and hormonal-related history, endocrinological features, sunlight exposure, specific cultural behaviours, use of topic corticosteroids and sunscreens. One hundred women (mean age 29.5 ± 13.7 years) were included with 200 age-matched controls. Duration of FH was 32.9 ± 42.2 months. There was a statistically significant relation between FH and hirsutism (P = 0.009), troubles of menstruations (P = 0.008), but not with acne (P = 0.23) and contraceptive oral (P = 0.06) drugs or with history of thyroid disorders (P = 0.13). For cultural factors, there were a statistical significant relation with rubbing by flannel glove (P < 0.05), use of dark soap (P = 0.009) and traditional masks (P < 0.05) but both groups were used to go to hammam. A strong relation was observed between FH and use of topical corticosteroids: 40% in the FH group vs. 5% in the control group (P < 0.05). Both groups used to apply sunscreens: 70% in the FH group and 67% in the control group where as there were no differences in the two groups for sun exposure. No statistical differences were observed regarding to age, phototypes and grade of parity. Our study demonstrated a relation between FH and hyperestrogenemia, rubbing with a friction glove, use of moroccan traditional masks and application of topical steroids. The eviction of all these triggering factors could be an adjuvant recommendation in the assessment of FH.

  15. Combinatorial control of heterogeneous cell populations

    NASA Astrophysics Data System (ADS)

    Piermarocchi, C.; Duxbury, P.; Paternostro, G.; Feala, J.; Tiziani, S.; Axelrod, J.; Chaudhury, A.; Choi, J.; McCulloch, A.; Cortes, J.

    2010-03-01

    In medicine, a recent pharmacological approach involves systematic discovery of combinatorial therapies, in which different drugs are simultaneously used to control different pathways associated with a cellular function. This control must occur with minimal response in other non-target cells exposed to treatment, i.e. it has to be selective. We have investigated the statistics of selective control of the human apoptosis (cell death) signaling network. We have built a model for a heterogeneous population of cells, characterized by a signaling network with identical topology, but having different link strengths. The control of the life/death signal is realized by acting with external perturbations, modeling the effect of drugs, on the nodes and on the signaling flow. Concepts from statistical physics and information theory, including entropy, frustration, and non-linearity have been used to characterize the general properties of selective control. This knowledge was used as a guide in designing algorithms for identifying selective perturbations. Some of these algorithms have been implemented in vitro in high throughput experiments on real cell lines where a large number of combinations of different drugs can be tested.

  16. [Control of population by economic means].

    PubMed

    Ji, M S

    1980-07-01

    Education alone cannot effectively control population growth. Benefit to the individual must be coordinated with the benefit to the community and the country. It is absolutely necessary and possible to control population by economic means. The economic policy in Tienjing includes: 1) give preference to single child families in child care, health benefits, education, and employment, and financially punish families with more than two children; 2) establish a better rationing policy, one not based on a per capita ration, and give preference to single child families; 3) establish retirement benefits and guarantee higher living standards for retirees who have either no children or only 1 or 2 children, and give paid sick leave to people experiencing complications following sterilization operations; 4) establish equal inheritance rights for both male and female offspring; and 5) give bonuses to units with excellent family planning results and to medical personnel with fewer complications during sterilization operations, and financially punish groups with poor family planning results. In order to effectively implement the economic means, coordinate bonuses with punishment, and coordinate local policies with those of the entire society. The key is strong leadership, but the voluntary and active involvement of the public insures success.

  17. Population medicine and control of epidemics.

    PubMed

    Benchaoui, Hafid

    2010-01-01

    Population medicine is an important component of veterinary care in livestock (farm animals) and companion animals (pets). This chapter covers some of the chemotherapeutic approaches undertaken at population level to control infectious diseases in domestic animals. Optimisation of health, productivity and welfare in livestock commonly entails implementation of whole-herd or whole-flock strategies to effectively counter the negative impact of infectious diseases. Gastro-intestinal and liver parasites of grazing cattle and sheep are endemic in most parts of the world and can result in significant production losses. Strategically timed anthelmintic treatments are instituted with the double objective of reducing worm burdens in infected animals and ensuring reduction of pasture contamination with infective larvae. Mastitis is another major endemic problem, particularly in cattle, which causes significant economic losses to dairy farmers globally. As a painful inflammatory condition of the cow's udder, clinical mastitis also raises animal welfare concerns. Prevention of clinical mastitis requires rigorous post-milking hygiene, identification and culling of chronically infected cows, attention to the cow's environment and therapeutic management of udder health during the dry period. A third condition that can cause high levels of morbidity and mortality is bacterial respiratory disease. Pneumonia in young livestock is often exacerbated by stressful transportation and co-mingling of animals from different herds. The welfare consequences and production losses can be significant. Antimicrobial treatment of pneumonic animals and, when appropriate, of in-contact animals living in the same air-space is an integral part of whole-herd respiratory disease management. The role of the veterinary profession is to also ensure that principles of population medicine are understood and adhered to by pet owners. The increase in pet ownership and the importance of the human-animal bond in

  18. Diet and risk of endometriosis in a population-based case–control study

    PubMed Central

    Trabert, Britton; Peters, Ulrike; De Roos, Anneclaire J.; Scholes, Delia; Holt, Victoria L.

    2012-01-01

    Diet plausibly has a role in the aetiology of endometriosis through effects on steroid hormone levels; however, few published studies have examined the diet and endometriosis risk. We evaluated dietary risk factors for endometriosis in a population-based case–control study. Cases were 284 Group Health (GH) enrollees aged 18–49 years with newly diagnosed, surgically confirmed endometriosis between 1996 and 2001. Controls were 660 randomly selected age-matched female GH enrollees without a history of endometriosis. Nutrients and selected food groups were assessed using the Women’s Health Initiative FFQ. OR of endometriosis risk associated with dietary exposures were estimated using unconditional logistic regression and adjusted for identified covariates. Increased total fat consumption was associated with decreased endometriosis risk (fourth quartile v. lowest: OR 0·5, 95% CI 0·2, 1·0, P-trend=0·12). Increased β-carotene consumption and servings/d of fruit were associated with increased risk (β-carotene third quartile v. lowest: OR 1·7, 95% CI 1·1, 2·6; fourth quartile v. lowest: OR 1·6, 95% CI 1·0, 2·5, P-trend 0·16; fruit >2 servings/d v. <1: OR 1·5, 95% CI 1·0, 2·3, P -trend=0·04). We also found a suggestion of decreased endometriosis risk associated with the consumption of dairy products (2 servings/d v. ≤1: OR 0·6, >2 servings/d v. ≤1: OR 0·7), but this association was not statistically significant for the highest tertile. The present study suggests that specific dietary components may be associated with endometriosis risk. PMID:20875189

  19. Computed tomography-guided in vivo cardiac orientation and correlation with ECG in individuals without structural heart disease and in age-matched obese and older individuals.

    PubMed

    Sathananthan, Gnalini; Aggarwal, Gunjan; Zahid, Simmi; Byth, Karen; Chik, William; Friedman, Daniel; Thiagalingam, Aravinda

    2015-05-01

    The cardiac axis in a structurally normal heart is influenced by a number of factors. We investigated the anatomical and electrical cardiac axes in middle-aged individuals without structural heart disease and compared this with age-matched obese and older individuals without structural heart disease. A retrospective study of controls included those between 30 and 60 years old with a normal body mass index (BMI), who were then compared with obese individuals between 30 and 60 years old and with individuals more than 60 years old with a normal BMI. The anatomical cardiac axis was determined along the long axis by cardiac computed tomography (CT) and correlated with the electrical cardiac axis on a surface electrocardiogram (ECG) in the frontal plane. A total of 124 patients were included. In the controls (n = 59), the mean CT axis was 38.1° ± 7.8° whilst the mean ECG axis was 51.8° ± 26.6°, Pearson r value 0.12 (P = 0.365). In the obese (n = 36), the mean CT axis was 25.1° ± 6.2° whilst the mean ECG axis was 20.1° ± 23.9°, Pearson r value 0.05 (P = 0.808). In the older group (n = 29), the mean CT axis was 34.4° ± 9.1° whilst the mean ECG axis was 34.4° ± 30.3°, Pearson r value 0.26 (P = 0.209). Obese individuals have a more leftward rotation of both axes than age-matched normals (P <0.0001), which could be secondary to elevation of the diaphragm. Older individuals have a more leftward rotation only of their electrical cardiac axis (P = 0.01), which could be a normal variant or reflect underlying conduction disturbances in this age group.

  20. Optimal control of Atlantic population Canada geese

    USGS Publications Warehouse

    Hauser, C.E.; Runge, M.C.; Cooch, E.G.; Johnson, F.A.; Harvey, W.F.

    2007-01-01

    Management of Canada geese (Branta canadensis) can be a balance between providing sustained harvest opportunity while not allowing populations to become overabundant and cause damage. In this paper, we focus on the Atlantic population of Canada geese and use stochastic dynamic programming to determine the optimal harvest strategy over a range of plausible models for population dynamics. There is evidence to suggest that the population exhibits significant age structure, and it is possible to reconstruct age structure from surveys. Consequently the harvest strategy is a function of the age composition, as well as the abundance, of the population. The objective is to maximize harvest while maintaining the number of breeding adults in the population between specified upper and lower limits. In addition, the total harvest capacity is limited and there is uncertainty about the strength of density-dependence. We find that under a density-independent model, harvest is maximized by maintaining the breeding population at the highest acceptable abundance. However if harvest capacity is limited, then the optimal long-term breeding population size is lower than the highest acceptable level, to reduce the risk of the population growing to an unacceptably large size. Under the proposed density-dependent model, harvest is maximized by maintaining the breeding population at an intermediate level between the bounds on acceptable population size; limits to harvest capacity have little effect on the optimal long-term population size. It is clear that the strength of density-dependence and constraints on harvest significantly affect the optimal harvest strategy for this population. Model discrimination might be achieved in the long term, while continuing to meet management goals, by adopting an adaptive management strategy.

  1. Population Control, Family Planning and Planned Parenthood.

    ERIC Educational Resources Information Center

    Hilmar, Norman A.

    Remarks in this article were made as part of a panel discussion presented at the Planned Parenthood-World Population combined Southeast Council and National Board Meeting, Savannah, Georgia, in May 1970. The problems and consequences of an increasing birth rate are indicated along with the need for reducing present rates of population growth and…

  2. 49 CFR 372.243 - Controlling distances and population data.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 false Controlling distances and population data. 372.243... population data. In the application of § 372.241: (a) Air-line distances or mileages about corporate limits of municipalities shall be used. (b) The population of any municipality shall be deemed to be...

  3. 49 CFR 372.243 - Controlling distances and population data.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 5 2012-10-01 2012-10-01 false Controlling distances and population data. 372.243... population data. In the application of § 372.241: (a) Air-line distances or mileages about corporate limits of municipalities shall be used. (b) The population of any municipality shall be deemed to be...

  4. 49 CFR 372.243 - Controlling distances and population data.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 5 2011-10-01 2011-10-01 false Controlling distances and population data. 372.243... population data. In the application of § 372.241: (a) Air-line distances or mileages about corporate limits of municipalities shall be used. (b) The population of any municipality shall be deemed to be...

  5. 49 CFR 372.243 - Controlling distances and population data.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 5 2013-10-01 2013-10-01 false Controlling distances and population data. 372.243... population data. In the application of § 372.241: (a) Air-line distances or mileages about corporate limits of municipalities shall be used. (b) The population of any municipality shall be deemed to be...

  6. 49 CFR 372.243 - Controlling distances and population data.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Controlling distances and population data. 372.243... population data. In the application of § 372.241: (a) Air-line distances or mileages about corporate limits of municipalities shall be used. (b) The population of any municipality shall be deemed to be...

  7. Population control programme in West Bengal.

    PubMed

    Reddy, K V

    1996-01-01

    Population size doubled over the period 1947-81 and continues to grow. Such a rapid increase in population size has serious repercussions upon socioeconomic development. Population growth threatens to nullify efforts to improve the condition of the poor. Indeed, all gains in the field of agriculture, industry, and national income look marginal when measured in per capita terms. The family welfare program seeks to promote, on a voluntary basis, responsible and planned parenthood of a two-child norm devoid of any bias for or against the sex of a given child. Use of the mass media and interpersonal communication to explain various methods of contraception and remove sociocultural barriers has led to an increase in the number of family planning acceptors in recent years. However, despite the family welfare program being in operation for four decades, population continues to grow at an alarming rate. It is clear that program strategy and mode of implementation must be reviewed. The state government of West Bengal is determined to implement the family welfare program effectively through the motivation and education of married couples, while making various types of contraceptive services available to the people. PMID:12347749

  8. Population control programme in West Bengal.

    PubMed

    Reddy, K V

    1996-01-01

    Population size doubled over the period 1947-81 and continues to grow. Such a rapid increase in population size has serious repercussions upon socioeconomic development. Population growth threatens to nullify efforts to improve the condition of the poor. Indeed, all gains in the field of agriculture, industry, and national income look marginal when measured in per capita terms. The family welfare program seeks to promote, on a voluntary basis, responsible and planned parenthood of a two-child norm devoid of any bias for or against the sex of a given child. Use of the mass media and interpersonal communication to explain various methods of contraception and remove sociocultural barriers has led to an increase in the number of family planning acceptors in recent years. However, despite the family welfare program being in operation for four decades, population continues to grow at an alarming rate. It is clear that program strategy and mode of implementation must be reviewed. The state government of West Bengal is determined to implement the family welfare program effectively through the motivation and education of married couples, while making various types of contraceptive services available to the people.

  9. A Particle Population Control Method for Dynamic Monte Carlo

    NASA Astrophysics Data System (ADS)

    Sweezy, Jeremy; Nolen, Steve; Adams, Terry; Zukaitis, Anthony

    2014-06-01

    A general particle population control method has been derived from splitting and Russian Roulette for dynamic Monte Carlo particle transport. A well-known particle population control method, known as the particle population comb, has been shown to be a special case of this general method. This general method has been incorporated in Los Alamos National Laboratory's Monte Carlo Application Toolkit (MCATK) and examples of it's use are shown for both super-critical and sub-critical systems.

  10. [On some theoretic issues about planned control of population].

    PubMed

    Zhou, Q

    1981-01-01

    There are basic differences between Marxian and Malthusian population thought: 1) For Marx, population is a social phenomenon--human reproduction belongs to social production and population laws are social laws influenced by the means of production. Marx recognized that human reproduction had both a natural and a social relationship, but Malthus population theory only acknowledges the natural relationship of human reproduction. Malthus believed that if population grows without interference, it will double every 25 years, or geometrically. It is evident Malthus substituted biological possibilities for the objective inevitability of population evolution, and natural population laws for social population laws. 2) Marx believed that social production is the unification of material production and human reproduction. Material production is controlled and necessitates control of human reproduction. For Malthus, the growth of the means of subsistence never catches up with the growth of the population, but Marx said that even though land is limited, the development of production forces is limitless. Marxist theory postulates that man is basically a producer, but that population must be planned because not everyone is a producer (e.g., children and the unskilled). 3) Malthus believed that in capitalistic countries unemployment, famine, and poverty stem from too many births by the laboring class, i.e., population determines the economy. The only solution to population problems is to have fewer children. For Marx, economics determines population problems. PMID:12159326

  11. Spatial variation in mortality risk for haematological malignancies near a petrochemical refinery: a population-based case-control study

    PubMed Central

    Di Salvo, Francesca; Meneghini, Elisabetta; Vieira, Veronica; Baili, Paolo; Mariottini, Mauro; Baldini, Marco; Micheli, Andrea; Sant, Milena

    2015-01-01

    Introduction The study investigated the geographic variation of mortality risk for hematological malignancies (HMs) in order to identify potential high-risk areas near an Italian petrochemical refinery. Material and methods A population-based case-control study was conducted and residential histories for 171 cases and 338 sex- and age-matched controls were collected. Confounding factors were obtained from interviews with consenting relatives for 109 HM deaths and 267 controls. To produce risk mortality maps, two different approaches were applied. We mapped (1) adptive kernel density relative risk estimation (KDE) for case-control studies which estimates a spatial relative risk function using the ratio between cases and controls’ densities, and (2) estimated odds ratios for case-control study data using generalized additive models (GAMs) to smooth the effect of location, a proxy for exposure, while adjusting for confounding variables. Results No high-risk areas for HM mortality were identified among all subjects (men and women combined), by applying both approaches. Using the adaptive KDE approach, we found a significant increase in death risk only among women in a large area 2–6 km southeast of the refinery and the application of GAMs also identified a similarly-located significant high-risk area among women only (global p-value<0.025). Potential confounding risk factors we considered in the GAM did not alter the results. Conclusion Both approaches identified a high-risk area close to the refinery among women only. Those spatial methods are useful tools for public policy management to determine priority areas for intervention. Our findings suggest several directions for further research in order to identify other potential environmental exposures that may be assessed in forthcoming studies based on detailed exposure modeling. PMID:26073202

  12. India gets serious about population control.

    PubMed

    Singh, S V

    1987-01-01

    India, under prime minister Rajiv Ghandi, has revamped its population policy, installing new goals, incentives, and emphasis on child health and later marriage. At the current growth rate of 2.2 % per year, India will reach 1.5 billion by 2025, becoming the world's most populous nation. New targets of the "national family welfare program" include reducing growth to 1.9% raising use of contraception from 35 to 42%, and cutting the birth rate from 33 to 29.1/1000, all by 1990. There will be an attempt to raise the average age of marriage for women by fostering education and employment. Immunization of all children, and supplementing their diets with iron, iodine and vitamin A will be among the efforts to use village health services more effectively. Non-government agencies and schools will participate in educating and motivating people. Attractive incentives such as pensions, insurance and bonds will be offered to those with 1 child or no sons.

  13. Population control and the women of India.

    PubMed

    Batra, B K

    1973-01-01

    14% of the world's population, (547,000,000 people) live on 2.4% of its land in India. 18% of the population of India live in 2690 cities, the rest in rural villages, with roughly an average of 700 people per village. The woman's role in India was mainly to produce children, most importantly sons. In 1956 India began the program of planned parenthood at a governmental level, aiming at restricting births. This met with some negativism on the part of the older generation especially due to its depriving them of the privilege and benefits of large families, and the lesser guarantee of a male heir. But due to the effects of agricultural and industrial reforms, rapid urbanization has occurred bringing better communication and helping to spread the ideas and information about family planning to the village. Urbanization also brought about a crashing economic situation. Motivation for planned parenthood has its most persuasive impetus when social and economic pressures are at their peak. Thus the message that a "small family is a happy family" has from necessity become accepted. The poor housing conditions with a total lack of privacy has contributed to the inability of Indian women to use more sophisticated methods of contraception. The pill is too expensive for most Indian women. The IUD therefore was the most practical to start with in 1956 and thereafter has been freely available. India's national leadership is committed to the success of the planned parenthood program which aims at the adoption of the norm of a small family as a social and personal ideal. The 2 facets of the program have been to persuade people to accept the new norms and to provide contraceptive services within easy reach. If the birth rate declines from its present level of 39 to 30 per 1000 by 1986, the population will still reach 792,000,000 by 1991, and 941,000,000 by 2001. The reason for the past increase in growth has been due to the rapidly declining death rate. Legislation has been passed to

  14. Population-based case–control study of soyfood intake and breast cancer risk in Shanghai

    PubMed Central

    Dai, Q; Shu, X-O; Jin, F; Potter, J D; Kushi, L H; Teas, J; Gao, Y-T; Zheng, W

    2001-01-01

    We evaluated the association of soyfood intake and breast cancer risk in a population-based case–control study among Chinese women in Shanghai. Included in the study were 1459 cases and 1556 age-matched controls, with respective response rates of 91.1% and 90.3%. Usual soyfood intake was assessed using a food frequency questionnaire (FFQ). Separate analyses were performed for all subjects and for the subset who reported no recent change in soyfood intake. The intake levels of soyfoods among women in Shanghai are high, with 96.6% women reporting soyfood consumption at least once a week. A statistically non-significant reduced risk (odds ratio (OR) = 0.78 95% CI = 0.52–1.16) of breast cancer was observed among those who reported eating soyfood at least once a week. Compared to those in the lowest decile intake group, women in the highest decile intake group had a 30% reduced risk of breast cancer (OR = 0.66, 95% CI = 0.46–0.95), but no monotonic dose–response relation was observed (P for trend, 0.28). Stratified analyses showed that the inverse association was restricted primarily among women who had a high body mass index (BMI), with an adjusted OR of 0.30 (95% CI = 0.10–0.94) observed for the highest intake group. The reduction in risk was stronger for breast cancer positive for both oestrogen receptor (ER) and progesterone receptor (PR) (OR = 0.44, 95% CI = 0.25–0.78) than those with other ER/PR status. More pronounced inverse associations were observed in analyses among those who reported no recent change in soyfood intake than those conducted in all subjects. A dose–response relation between soyfood intake and breast cancer risk was observed in this subset of women (P for trend, 0.02), with an OR of 0.46 (95%CI = 0.28–0.75) for those in the highest decile intake group. No clear monotonic dose–response relation was found between soyfood intake and breast cancer risk among regular soy eaters, but nevertheless the results suggest that regular

  15. High Intake of Energy and Fat in Southwest Chinese Women with PCOS: A Population-Based Case-Control Study

    PubMed Central

    Zhang, Jing; Liu, Ying; Liu, Xiaofang; Xu, Liangzhi; Zhou, Lingling; Tang, Liulin; Zhuang, Jing; Guo, Wenqi; Hu, Rong

    2015-01-01

    Background Polycystic ovary syndrome (PCOS) is a common reproductive endocrinological disease with heterogeneous phenotype. Obesity contributes to the increased prevalence and severity of PCOS. Whether the intakes of major nutrients are higher in Chinese PCOS patients is still unknown. Objectives To study the intakes of total energy, protein, fat and carbohydrate in Southwest Chinese PCOS patients. Methods 1854 women were included in the cross-sectional study. A population-based case-control study was conducted. The dietary habits and nutrients intake status of 169 PCOS patients and 338 age-matched controls were investigated by the method of semi-quantitative food frequency questionnaire. Results The actual intake of total energy (P = 0.01) and fat (P = 0.01) were higher, but carbohydrate was lower (P = 0.01) in PCOS patients as compared with the controls. The energy percentage supplied by protein (12.33%±2.27% vs. 19.26%±5.91%, P<0.001) and carbohydrate (48.72%±6.41% vs. 68.31%±8.37%, P<0.001) were lower in Southwest Chinese PCOS patients than those of control, however, the energy percentage supplied by fat was higher (38.95%±5.71% vs. 12.42%±5.13%, P<0.001) in PCOS. Conclusions Limit the intake of total energy and fat shall be recommended to the Southwest Chinese PCOS patients. Women with PCOS in Southwest China shall consult with the nutritionist for improving the dietary structure. PMID:25993656

  16. Optimal control methods for controlling bacterial populations with persister dynamics

    NASA Astrophysics Data System (ADS)

    Cogan, N. G.

    2016-06-01

    Bacterial tolerance to antibiotics is a well-known phenomena; however, only recent studies of bacterial biofilms have shown how multifaceted tolerance really is. By joining into a structured community and offering shared protection and gene transfer, bacterial populations can protect themselves genotypically, phenotypically and physically. In this study, we collect a line of research that focuses on phenotypic (or plastic) tolerance. The dynamics of persister formation are becoming better understood, even though there are major questions that remain. The thrust of our results indicate that even without detailed description of the biological mechanisms, theoretical studies can offer strategies that can eradicate bacterial populations with existing drugs.

  17. The politics of population: birth control and the eugenics movement.

    PubMed

    Gordon, L

    1974-01-01

    The birth control movement and the population control movement became inseparable in people's minds during the early years of the birth control movement, led by Margaret Sanger in 1915. Emma Goldman and Margaret Sanger defied obscenity laws by disseminating information on contraception. The birth control movement was concerned with individual choice and reproductive self determination. Population control referred to a large-scale social policy of limiting births throughout a whole society or in certain groups for the purpose of changing economic, ecological and/or political conditions. Population control ideas were dominated by eugenics and marred by racism and nativism in the United States. Unfortunately, eugenic ideas and population control were often confused with birth control, especially by poor, lower class women. Real democracy in population control requires that women, not men, have the reproductive choice. It is the material basis for liberation. If a woman's desire for children interferes with a reasonable and democratic social plan to lower birth rates, the woman should be offered educational and economic opportunities as an alternative to childbearing. Eugenics and imperialism were closely related in American and English history, focussing first on one group of immigrants then another.

  18. Control of Population Flow in Coherently Driven Quantum Ladders

    SciTech Connect

    Garcia-Fernandez, Ruth; Bergmann, Klaas; Ekers, Aigars; Yatsenko, Leonid P.; Vitanov, Nikolay V.

    2005-07-22

    A technique for adiabatic control of the population flow through a preselected decaying excited level in a three-level quantum ladder is presented. The population flow through the intermediate or upper level is controlled efficiently and robustly by varying the pulse delay between a pair of partly overlapping coherent laser pulses. The technique is analyzed theoretically and demonstrated in an experiment with Na{sub 2} molecules.

  19. The value of monitoring to control evolving populations

    PubMed Central

    Fischer, Andrej; Mustonen, Ville

    2015-01-01

    Populations can evolve to adapt to external changes. The capacity to evolve and adapt makes successful treatment of infectious diseases and cancer difficult. Indeed, therapy resistance has become a key challenge for global health. Therefore, ideas of how to control evolving populations to overcome this threat are valuable. Here we use the mathematical concepts of stochastic optimal control to study what is needed to control evolving populations. Following established routes to calculate control strategies, we first study how a polymorphism can be maintained in a finite population by adaptively tuning selection. We then introduce a minimal model of drug resistance in a stochastically evolving cancer cell population and compute adaptive therapies. When decisions are in this manner based on monitoring the response of the tumor, this can outperform established therapy paradigms. For both case studies, we demonstrate the importance of high-resolution monitoring of the target population to achieve a given control objective, thus quantifying the intuition that to control, one must monitor. PMID:25587136

  20. Age-structured optimal control in population economics.

    PubMed

    Feichtinger, Gustav; Prskawetz, Alexia; Veliov, Vladimir M

    2004-06-01

    This paper brings both intertemporal and age-dependent features to a theory of population policy at the macro-level. A Lotka-type renewal model of population dynamics is combined with a Solow/Ramsey economy. We consider a social planner who maximizes an aggregate intertemporal utility function which depends on per capita consumption. As control policies we consider migration and saving rate (both age-dependent). By using a new maximum principle for age-structured control systems we derive meaningful results for the optimal migration and saving rate in an aging population. The model used in the numerical calculations is calibrated for Austria.

  1. Degenerated intervertebral disc prolapse and its association of collagen I alpha 1 Spl gene polymorphism: A preliminary case control study of Indian population

    PubMed Central

    Anjankar, Shailendra D; Poornima, Subhadra; Raju, Subodh; Jaleel, MA; Bhiladvala, Dilnavaz; Hasan, Qurratulain

    2015-01-01

    Background: Degenerated disc disease (DDD) is a common disorder responsible for increased morbidity in a productive age group. Its etiology is multifactorial and genetic factors have been predominantly implicated. Disc prolapse results due to tear in the annulus, which is a fibrous structure composed largely of type I collagen. Functional polymorphism at the Sp1 site of the collagen I alpha 1 (COL1A1) gene has shown a positive association with DDD in Dutch and Greek populations. The purpose of this study was to assess COL1A1 Sp1 gene polymorphism in the Indian population. Materials and Methods: Fifty clinically and radiologically proven patients with disc prolapse requiring surgery were included as cases and 50 healthy, age-matched volunteers served as controls. After isolating DNA from their blood sample, genotyping for COL1A1 polymorphism (rs1800012) was performed and identified as GG, GT, and TT. Results: The mean age and body mass index in cases and controls were similar. 76% of the patients were males. The most common site of disc degeneration was L4–L5 (36%), followed by L5–S1 (34%). Homozygous–GG, heterozygous GT, and homozygous TT genotypes were seen in 38 (76%), 10 (20%) and 2 (4%) cases respectively, controls had similar percentage of genotypes as well. The alleles in cases and the control group showed no significant difference (P = 0.6744) and followed the Hardy–Weinberg Equilibrium in the study population. Conclusion: The COL1A1 (rs1800012) is in Hardy–Weinberg equilibrium in the present subset of Indian population. But taken as a single factor, it was not found to be associated with DDD in this preliminary study. Disc degeneration is multifactorial and also anticipated to be a result of multiple genes involvement and gene-gene interaction. PMID:26806964

  2. Biological control agents elevate hantavirus by subsidizing deer mouse populations.

    PubMed

    Pearson, Dean E; Callaway, Ragan M

    2006-04-01

    Biological control of exotic invasive plants using exotic insects is practiced under the assumption that biological control agents are safe if they do not directly attack non-target species. We tested this assumption by evaluating the potential for two host-specific biological control agents (Urophora spp.), widely established in North America for spotted knapweed (Centaurea maculosa) control, to indirectly elevate Sin Nombre hantavirus by providing food subsidies to populations of deer mice (Peromyscus maniculatus), the primary reservoir for the virus. We show that seropositive deer mice (mice testing positive for hantavirus) were over three times more abundant in the presence of the biocontrol food subsidy. Elevating densities of seropositive mice may increase risk of hantavirus infection in humans and significantly alter hantavirus ecology. Host specificity alone does not ensure safe biological control. To minimize indirect risks to non-target species, biological control agents must suppress pest populations enough to reduce their own numbers. PMID:16623730

  3. Dog population management for the control of human echinococcosis.

    PubMed

    Kachani, Malika; Heath, David

    2014-11-01

    Cystic and alveolar hydatid disease of humans caused by infection with Echinococcus granulosus or Echinococcus multilocularis are significant zoonoses in developing countries. For human infections, the main definitive host is the dog, and reduction in the population of unwanted dogs, together with anthelmintic treatment of wanted dogs, are recommended control procedures for these zoonoses. Both owned and unowned dogs have been shown to be a major source of Echinococcus spp. infection in developing countries. Unowned dogs are the most challenging category in dog population management for the control of major zoonotic diseases. Unowned dogs are those dogs that do not have an owner, and those dogs whose owner cannot readily be identified. Control of numbers of unowned dogs can be done in various ways if funds are available. Fertility control and humane euthanasia are likely to be the most effective procedures in developing countries. Fertility control requires significant funding, and where resources are scarce humane euthanasia may be the most effective option. Both procedures are ongoing events, with no predictable end point. This paper examines the sociology and technology for the population management of owned and unowned dogs, specifically for the reduction of human hydatid disease. Examples are given for developing and developed countries. Although a "One Health" approach is desirable, the technology for hydatid control is different from that for rabies, and FAO Animal Welfare recommendations for dog population management should be adjusted accordingly.

  4. The population model of bone remodelling employed the optimal control.

    PubMed

    Moroz, Adam

    2012-11-01

    Several models have been developed in recent years which apply population dynamics methods to describe the mechanisms of bone remodelling. This study incorporates the population kinetics model of bone turnover (including the osteocyte loop regulation) with the optimal control technique. Model simulations have been performed with a wide range of rate parameters using the Monte Carlo method. The regression method has also been used to investigate the interdependence of the location of equilibrium and the characteristics of the equilibrium/relaxation time on the rate parameters employed. The dynamic optimal control outlook for the regulation of bone remodelling processes, in the context of the osteocyte-control population model, has been discussed. Optimisation criteria have been formulated from the perspective of the energetic and metabolic losses in the tissue, with respect to the performance of the bone multicellular unit.

  5. Is drinking water a risk factor for endemic cryptosporidiosis? A case-control study in the immunocompetent general population of the San Francisco Bay Area

    PubMed Central

    Khalakdina, Asheena; Vugia, Duc J; Nadle, Joelle; Rothrock, Gretchen A; Colford, John M

    2003-01-01

    Background Cryptosporidiosis, caused by Cryptosporidium, is an enteric illness that has received much attention as an infection of immunocompromised persons as well as in community outbreaks (frequently waterborne). There are, however, no studies of the risk factors for sporadic community-acquired cryptosporidiosis in the immunocompetent US population. We undertook a case-control study in the San Francisco Bay Area as part of a national study sponsored by the Centers for Disease Control and Prevention to ascertain the major routes of transmission for endemic cryptosporidiosis, with an emphasis on evaluating risk from drinking water. Methods Cases were recruited from a population-based, active surveillance system and age-matched controls were recruited using sequential random-digit dialing. Cases (n = 26) and controls (n = 62) were interviewed by telephone using a standardized questionnaire that included information about the following exposures: drinking water, recreational water, food items, travel, animal contact, and person-to-person fecal contact, and (for adults) sexual practices. Results In multivariate conditional logistic regression analyses no significant association with drinking water was detected. The major risk factor for cryptosporidiosis in the San Francisco Bay Area was travel to another country (matched odds ratio [95% confidence interval]: 24.1 [2.6, 220]). Conclusion The results of this study do not support the hypothesis that drinking water is an independent risk factor for cryptosporidiosis among the immunocompetent population. These findings should be used to design larger studies of endemic cryptosporidiosis to elucidate the precise mechanisms of transmission, whether waterborne or other. PMID:12689343

  6. Traps to control and estimate populations of Glossina species.

    PubMed

    Ryan, L; Molyneux, D H; Kuzoe, F A; Baldry, D A

    1981-09-01

    Biconical traps were used to capture continuously Glossina palpalis s.l. in Ivory Coast and G. morsitans centralis in Zambia for 19 and 20 days respectively. Both fly populations declined markedly during the continuous trapping period though populations subjected to intermittent trapping or where the traps were very widely spaced did not do so to the same extent. Fly density was estimated by applying the principles of removal trapping and were compared with other trapping studies. The results demonstrated that biconical traps removed 7% of the female component of the population each day and that this 7% removal value was itself a measure of absolute trapping efficiency; providing a novel means of population estimation. The potential of traps to control tsetse and thus break trypanosome transmission cycles or reduce 'challenge' on a self-help basis at the village level is discussed.

  7. Control of nuisance populations of crayfish with traps and toxicants

    USGS Publications Warehouse

    Bills, T.D.; Marking, L.L.

    1988-01-01

    Crayfish have long been a nuisance in fish-rearing ponds at fish hatcheries. The rusty crayfish (Orconectes rusticus ) has displaced endemic species and caused serious declines of aquatic plants in some ponds and lakes in the midwestern USA. The authors attempted to evaluate the effect of intensive trapping on a crayfish population and to identify a selective chemical control agent and evaluate its effectiveness under field conditions. A crayfish population in a small pond was suppressed but not eliminated by trapping: adults were effectively harvested but efficiency diminished sharply as the population declined. Of 19 chemicals tested as possible control agents for crayfish, a synthetic pyrethroid (Baythroid) was by far the most toxic; 25 mu g/L produced a complete kill of crayfish in the pond and was also the most selective for crayfish in laboratory tests.

  8. Population Control, Myth or Fact as a National Goal.

    ERIC Educational Resources Information Center

    Zarembinski, Clem

    Evidence presented in this paper substantiates the position that: (1) the United States is pursuing a national goal and foreign policy of population control; and (2) a conflict about this goal could arise within the minds of many people. To support these two facts, the author has outlined statements giving an overview about the profusion of…

  9. Early detection of cancer in the general population: a blinded case–control study of p53 autoantibodies in colorectal cancer

    PubMed Central

    Pedersen, J W; Gentry-Maharaj, A; Fourkala, E-O; Dawnay, A; Burnell, M; Zaikin, A; Pedersen, A E; Jacobs, I; Menon, U; Wandall, H H

    2013-01-01

    Background: Recent reports from cancer screening trials in high-risk populations suggest that autoantibodies can be detected before clinical diagnosis. However, there is minimal data on the role of autoantibody signatures in cancer screening in the general population. Methods: Informative p53 peptides were identified in sera from patients with colorectal cancer using an autoantibody microarray with 15-mer overlapping peptides covering the complete p53 sequence. The selected peptides were evaluated in a blinded case–control study using stored serum from the multimodal arm of the United Kingdom Collaborative Trial of Ovarian Cancer Screening where women gave annual blood samples. Cases were postmenopausal women who developed colorectal cancer following recruitment, with 2 or more serum samples preceding diagnosis. Controls were age-matched women with no history of cancer. Results: The 50 640 women randomised to the multimodal group were followed up for a median of 6.8 (inter-quartile range 5.9–8.4) years. Colorectal cancer notification was received in 101 women with serial samples of whom 97 (297 samples) had given consent for secondary studies. They were matched 1 : 1 with 97 controls (296 serial samples). The four most informative peptides identified 25.8% of colorectal cancer patients with a specificity of 95%. The median lead time was 1.4 (range 0.12–3.8) years before clinical diagnosis. Conclusion: Our findings suggest that in the general population, autoantibody signatures are detectable during preclinical disease and may be of value in cancer screening. In colorectal cancer screening in particular, where the current need is to improve compliance, it suggests that p53 autoantibodies may contribute towards risk stratification. PMID:23169294

  10. Serum uric acid is associated with increased risk of idiopathic venous thromboembolism in high HDL-C population: A case-control study

    PubMed Central

    YU, MIAO; LING, KEN; TENG, YUNFEI; LI, QIN; MEI, FEI; LI, YIQING; OUYANG, CHENXI

    2016-01-01

    Many studies have indicated that metabolic disorders are positively correlated with idiopathic venous thromboembolism (VTE), whereas the risk factor serum uric acid (SUA) for idiopathic VTE has yet to be investigated. In this retrospective case-control study, 276 idiopathic VTE patients and 536 gender- and age-matched control subjects were included. The subjects in the case and control groups exhibiting common known VTE risk factors and the patients with a first VTE onset in one month were excluded. For the control group, primary and secondary VTE patients were excluded. High-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol, total cholesterol, fasting blood glucose, and current smoking were significantly associated with idiopathic VTE in the univariate analysis. Hyperuricemia was detected in 56/276 (20.29%) idiopathic patients compared with 71/536 (13.25%) in the control group. HDL-C was considered the most prominent interactive factor for SUA in idiopathic VTE by the interaction analysis. After testing for the interaction terms, SUA was closely associated with idiopathic VTE in the high HDL-C population (P=0.0026 for interaction), while there was no such correlation in the low HDL-C group. The results indicated no obvious correlation between triglyceride and hypertension to idiopathic VTE. In conclusion, SUA is closely associated with an increased risk of idiopathic VTE in the high HDL-C population. The abnormality of SUA may act as an important linkage between atherosclerosis and idiopathic VTE through HDL-C. PMID:27284315

  11. From population control to "reproductive rights": ideological influences in population policy.

    PubMed

    Grimes, S

    1998-01-01

    The author examines some of the ideological influences which have shaped population control policy in recent decades and considers the growing critique of what is now regarded as a narrowly focused policy, one which is based upon a simplistic definition and analysis of population growth in the less developed world. Focus is given to the important role of professional demographers in the US, who tailored their theories to provide a respectable justification for questionable policy intervention. The emergence of a population establishment in the US, based upon interconnected networks of foundations, private population organizations, and university population centers is outlined. These institutions provide a willing conduit for US government funding through the US Agency for International Development. Relevant interdisciplinary literature has raised concerns over issues such as the outside intervention in national sovereignty, ethical aspects associated with the implementation of fertility control programs, the exclusion of Third World scholars from research programs conducted in their own countries, and the unwillingness of programs to consider complex social and cultural dimensions of high fertility.

  12. Population control, distribution, and manpower problems of Thailand.

    PubMed

    Debavalya, N

    1981-12-01

    Responsive population policies proposed or underway in Thailand are intended to meet the challenges inherent in rapid population growth, rural to urban movement, and an increasing labor force. Data from several national sample surveys conducted from 1969-1975 highlight changing reproductive patterns. The annual population growth rate of about 3% between 1960-70 shows evidence of decline. Between 1969 and 1975, marital fertility has decreased by close to 20%. Contraceptive utilization has risen from 15% to 37% among currently married women, and by 1975, almost all Thai women indicated familiarity with birth control methods. The preferred number of children is also declining and differences in effective population control between rural and urban populations is diminishing. Governmental support of family planning was formalized in 1970 with the establishment of the National Family Planning Program. The success attributed to the program is in part due to its integration into the Ministry of Public Health's network of general health facilities. Rapid urbanization of the Bangkok metropolis has created over 300 slum areas within the city that lack basic urban infrastructure and services, excessive traffic, and uncontrolled land use problems. The governmental response includes plans to slow migration by creating incentives to establish industries in provincial areas, by decentralizing some government agencies, by developing additional regional centers with emphasis on control of land use, provision of adequate urban infrastructure, creation of new jobs and integrated urban, rural, and regional planning. Thailand's period of rapid population growth contributes to its expanding labor force. Although the unemployment rate is relatively low, 2.2% in 1978, underemployment, due to seasonal variations in demand for agricultural labor, is a significant problem. Regular national labor force surveys are underway so that more useful information for determining government policies and

  13. Population control, distribution, and manpower problems of Thailand.

    PubMed

    Debavalya, N

    1981-12-01

    Responsive population policies proposed or underway in Thailand are intended to meet the challenges inherent in rapid population growth, rural to urban movement, and an increasing labor force. Data from several national sample surveys conducted from 1969-1975 highlight changing reproductive patterns. The annual population growth rate of about 3% between 1960-70 shows evidence of decline. Between 1969 and 1975, marital fertility has decreased by close to 20%. Contraceptive utilization has risen from 15% to 37% among currently married women, and by 1975, almost all Thai women indicated familiarity with birth control methods. The preferred number of children is also declining and differences in effective population control between rural and urban populations is diminishing. Governmental support of family planning was formalized in 1970 with the establishment of the National Family Planning Program. The success attributed to the program is in part due to its integration into the Ministry of Public Health's network of general health facilities. Rapid urbanization of the Bangkok metropolis has created over 300 slum areas within the city that lack basic urban infrastructure and services, excessive traffic, and uncontrolled land use problems. The governmental response includes plans to slow migration by creating incentives to establish industries in provincial areas, by decentralizing some government agencies, by developing additional regional centers with emphasis on control of land use, provision of adequate urban infrastructure, creation of new jobs and integrated urban, rural, and regional planning. Thailand's period of rapid population growth contributes to its expanding labor force. Although the unemployment rate is relatively low, 2.2% in 1978, underemployment, due to seasonal variations in demand for agricultural labor, is a significant problem. Regular national labor force surveys are underway so that more useful information for determining government policies and

  14. SOC in a population model with global control

    NASA Astrophysics Data System (ADS)

    Bröker, Hans-Martin; Grassberger, Peter

    We study a plant population model introduced recently by Wallinga (OIKOS 74 (1995) 377). It is similar to the contact process (‘simple epidemic’, ‘directed percolation’), but instead of using an infection or recovery rate as control parameter, the population size is controlled directly and globally by removing excess plants. We show that the model is very closely related to directed percolation (DP). Anomalous scaling laws appear in the limit of large populations, small densities, and long times. These laws, associated critical exponents, and even some non-universal parameters, can be related to those of DP. As in invasion percolation and in other models where the rôles of control and order parameters are interchanged, the critical value pc of the wetting probability p is obtained in the scaling limit as singular point in the distribution of removal rates. We show that a mean field type approximation leads to a model studied by Zhang et al. (J. Stat. Phys. 58 (1990) 849). Finally, we verify the claim of Wallinga that family extinction in a marginally surviving population is governed by DP scaling laws, and speculate on applications to human mitochondrial DNA.

  15. [A strategy for birth control based on population trends].

    PubMed

    Kong, S K; Jang, Y

    1982-12-01

    The objective of this study is to analyze behavioral changes in fertility in the Republic of Korea since the development of a national population policy and program in the 1960s. Recommendations for future birth control policies are suggested. In addition, changes in population structure are described, including the increase in the number of women in the reproductive ages, the increase in the number of women living in urban areas, and the high percentage of women who want many children and who do not wish to use contraception. (summary in ENG)

  16. Universality in exact quantum state population dynamics and control

    SciTech Connect

    Wu, Lian-Ao; Segal, Dvira; Brumer, Paul; Egusquiza, Inigo L.

    2010-09-15

    We consider an exact population transition, defined as the probability of finding a state at a final time that is exactly equal to the probability of another state at the initial time. We prove that, given a Hamiltonian, there always exists a complete set of orthogonal states that can be employed as time-zero states for which this exact population transition occurs. The result is general: It holds for arbitrary systems, arbitrary pairs of initial and final states, and for any time interval. The proposition is illustrated with several analytic models. In particular, we demonstrate that in some cases, by tuning the control parameters, a complete transition might occur, where a target state, vacant at t=0, is fully populated at time {tau}.

  17. Internal models for interpreting neural population activity during sensorimotor control.

    PubMed

    Golub, Matthew D; Yu, Byron M; Chase, Steven M

    2015-01-01

    To successfully guide limb movements, the brain takes in sensory information about the limb, internally tracks the state of the limb, and produces appropriate motor commands. It is widely believed that this process uses an internal model, which describes our prior beliefs about how the limb responds to motor commands. Here, we leveraged a brain-machine interface (BMI) paradigm in rhesus monkeys and novel statistical analyses of neural population activity to gain insight into moment-by-moment internal model computations. We discovered that a mismatch between subjects' internal models and the actual BMI explains roughly 65% of movement errors, as well as long-standing deficiencies in BMI speed control. We then used the internal models to characterize how the neural population activity changes during BMI learning. More broadly, this work provides an approach for interpreting neural population activity in the context of how prior beliefs guide the transformation of sensory input to motor output.

  18. Surveillance and control of meningococcal meningitis epidemics in refugee populations.

    PubMed

    Moore, P S; Toole, M J; Nieburg, P; Waldman, R J; Broome, C V

    1990-01-01

    Epidemics of communicable diseases pose a direct threat to refugee and internally displaced populations, and could lead to high mortality rates and a disruption of basic health care services. Several large refugee populations live in regions of high meningococcal disease endemicity and their camps are at risk for outbreaks of meningococcal meningitis. Surveillance in these camps allows early detection and control of impending outbreaks. Confirmation of meningococcal disease can be performed under field conditions using simple techniques, such as latex agglutination. Isolates should be obtained for serogroup confirmation and antibiotic sensitivity studies at reference laboratories. Serogroup information is used to determine the risk of widespread epidemic disease and the utility of available vaccines. During epidemics, treatment regimens should be standardized, preferably with an effective single-dose antibiotic. Mass vaccination campaigns should be initiated, the populations at high risk being targeted for vaccination as quickly as possible. When the risk of epidemic disease is deemed to be high, preemptive vaccination may be warranted. Daily surveillance using a simple case definition is essential during an epidemic to determine the effectiveness of control measures and to delineate high-risk groups for vaccination or chemoprophylaxis. Many of these recommendations can be applied also to other populations in developing countries.

  19. Dynamic control and quantification of bacterial population dynamics in droplets

    PubMed Central

    Huang, Shuqiang; Srimani, Jaydeep K.; Lee, Anna J.; Zhang, Ying; Lopatkin, Allison J.; Leong, Kam W.; You, Lingchong

    2015-01-01

    Culturing and measuring bacterial population dynamics are critical to develop insights into gene regulation or bacterial physiology. Traditional methods, based on bulk culture to obtain such quantification, have the limitations of higher cost/volume of reagents, non-amendable to small size of population and more laborious manipulation. To this end, droplet-based microfluidics represents a promising alternative that is cost-effective and high-throughput. However, difficulties in manipulating the droplet environment and monitoring encapsulated bacterial population for long-term experiments limit its utilization. To overcome these limitations, we used an electrode-free injection technology to modulate the chemical environment in droplets. This ability is critical for precise control of bacterial dynamics in droplets. Moreover, we developed a trapping device for long-term monitoring of population dynamics in individual droplets for at least 240 h. We demonstrated the utility of this new microfluidic system by quantifying population dynamics of natural and engineered bacteria. Our approach can further improve the analysis for systems and synthetic biology in terms of manipulability and high temporal resolution. PMID:26005763

  20. Health education campaign on population control: lessons from Iran.

    PubMed

    Montazeri, A

    1995-11-01

    A descriptive study was carried out in Tehran, the capital of Iran, to investigate a health education campaign on population control. A sample of 68 adults aged 20 to 40 years participated in the study. Each respondent was shown a picture of the campaign. They then filled in a short questionnaire. The main objectives of the study were to measure recall rates and to assess attitude of the subjects. The study results show that recall rates were high (78%), 68% of respondents claimed that the campaign is likely to change their attitudes towards population control, and 87% of participants perceived the main idea of the campaign correctly. The study findings show that there are some significant associations between demographic variables (marital status, having child or not) and perception of the campaign. These may lead health educators and health promoters to communicate more effectively and efficiently in the context of family planning. In countries with a large number of young people, health education campaigns on population control with respect to social values of each society and moral considerations are recommended.

  1. Health education campaign on population control: lessons from Iran.

    PubMed

    Montazeri, A

    1995-11-01

    A descriptive study was carried out in Tehran, the capital of Iran, to investigate a health education campaign on population control. A sample of 68 adults aged 20 to 40 years participated in the study. Each respondent was shown a picture of the campaign. They then filled in a short questionnaire. The main objectives of the study were to measure recall rates and to assess attitude of the subjects. The study results show that recall rates were high (78%), 68% of respondents claimed that the campaign is likely to change their attitudes towards population control, and 87% of participants perceived the main idea of the campaign correctly. The study findings show that there are some significant associations between demographic variables (marital status, having child or not) and perception of the campaign. These may lead health educators and health promoters to communicate more effectively and efficiently in the context of family planning. In countries with a large number of young people, health education campaigns on population control with respect to social values of each society and moral considerations are recommended. PMID:8570803

  2. Risk factors associated with a breast cancer in a population of Moroccan women whose age is less than 40 years: a case control study

    PubMed Central

    Laamiri, Fatima Zahra; Hasswane, Nadia; Kerbach, Aicha; Aguenaou, Hassan; Taboz, Youness; Benkirane, Hassna; Mrabet, Mustapha; Amina, Barkat

    2016-01-01

    Introduction Breast cancer is the most common cancer in morocco women were it occupies the first place in term of incidence and mortality. The aim of the present paper is to evaluate the risk factors associated with a breast cancer in a population of Moroccan women. Methods A case-control study was conducted with population women whose age is less than 40 years during 2008-2010 at the National Institute of Oncology of Rabat. These women were interviewed for Epidemiological information and risk factor for breast cancer. Results Included in this study were 124 cases and 148 age matched controls. No statistically significant case-control difference was found for the early age of menarche (OR = 2.474; CI 95%: 1.354- 4.521), and family antecedents of first degree of breast cancer (OR = 11.556; 95% CI: 2.548-52.411). However physical activity (OR = 0.507; 95% CI: 0.339 -0.757) early maternity age (OR = 0.212; 95% CI: 0.087 - 0.514), multiparity (OR = 0.742; 95% CI: 0.359 -1.539) and breastfeeding than 6 months (OR = 0.739; 95% CI: 0.357 -1.523) appear as significant protective factors. Conclusion This study show the criminalization of only part of the known risk factors of breast cancer in this age group and confirms the probable protective role of physical activity and factors related to life reproductive women in our study (early childbearing, multiparity and lactation). PMID:27583083

  3. Cytogenetic monitoring of industrial populations potentially exposed to genotoxic chemicals and of control populations.

    PubMed

    de Jong, G; van Sittert, N J; Natarajan, A T

    1988-03-01

    Currently the most applied technique for monitoring biological effects of exposure to genotoxic chemicals in industrial workers is the measurement of chromosome aberrations in peripheral blood lymphocytes. In the Shell petrochemical complex in The Netherlands cytogenetic monitoring studies have been carried out from 1976 till 1981 inclusive, in workers potentially exposed to a variety of genotoxic chemicals, i.e. vinyl chloride, ethylene oxide, benzene, epichlorohydrin, epoxy resins. Average exposure levels to these chemicals were well below the occupational exposure limits. Results of these studies indicate that no biologically significant increase in the frequencies of chromosome aberrations in the exposed populations occurred compared with control populations. Our experience with this methodology has shown that the results of chromosome analyses are difficult to interpret, due to the variable and high background levels of chromosome aberrations in control populations and in individuals. It is concluded that the method is not sufficiently sensitive for routine monitoring of cytogenetic effects in workers exposed to the low levels of genotoxic compounds.

  4. 50 CFR 21.61 - Population control of resident Canada geese.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Canada goose population in question. However, resumption of injuries caused by growth of the population... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Population control of resident Canada... Populations § 21.61 Population control of resident Canada geese. (a) Which Canada geese are covered by...

  5. Controllable coherent population transfers in superconducting qubits for quantum computing.

    PubMed

    Wei, L F; Johansson, J R; Cen, L X; Ashhab, S; Nori, Franco

    2008-03-21

    We propose an approach to coherently transfer populations between selected quantum states in one- and two-qubit systems by using controllable Stark-chirped rapid adiabatic passages. These evolution-time insensitive transfers, assisted by easily implementable single-qubit phase-shift operations, could serve as elementary logic gates for quantum computing. Specifically, this proposal could be conveniently demonstrated with existing Josephson phase qubits. Our proposal can find an immediate application in the readout of these qubits. Indeed, the broken parity symmetries of the bound states in these artificial atoms provide an efficient approach to design the required adiabatic pulses.

  6. Internal models for interpreting neural population activity during sensorimotor control

    PubMed Central

    Golub, Matthew D; Yu, Byron M; Chase, Steven M

    2015-01-01

    To successfully guide limb movements, the brain takes in sensory information about the limb, internally tracks the state of the limb, and produces appropriate motor commands. It is widely believed that this process uses an internal model, which describes our prior beliefs about how the limb responds to motor commands. Here, we leveraged a brain-machine interface (BMI) paradigm in rhesus monkeys and novel statistical analyses of neural population activity to gain insight into moment-by-moment internal model computations. We discovered that a mismatch between subjects’ internal models and the actual BMI explains roughly 65% of movement errors, as well as long-standing deficiencies in BMI speed control. We then used the internal models to characterize how the neural population activity changes during BMI learning. More broadly, this work provides an approach for interpreting neural population activity in the context of how prior beliefs guide the transformation of sensory input to motor output. DOI: http://dx.doi.org/10.7554/eLife.10015.001 PMID:26646183

  7. Signal Propagation between Neuronal Populations Controlled by Micropatterning

    PubMed Central

    Albers, Jonas; Offenhäusser, Andreas

    2016-01-01

    The central nervous system consists of an unfathomable number of functional networks enabling highly sophisticated information processing. Guided neuronal growth with a well-defined connectivity and accompanying polarity is essential for the formation of these networks. To investigate how two-dimensional protein patterns influence neuronal outgrowth with respect to connectivity and functional polarity between adjacent populations of neurons, a microstructured model system was established. Exclusive cell growth on patterned substrates was achieved by transferring a mixture of poly-l-lysine and laminin to a cell-repellent glass surface by microcontact printing. Triangular structures with different opening angle, height, and width were chosen as a pattern to achieve network formation with defined behavior at the junction of adjacent structures. These patterns were populated with dissociated primary cortical embryonic rat neurons and investigated with respect to their impact on neuronal outgrowth by immunofluorescence analysis, as well as their functional connectivity by calcium imaging. Here, we present a highly reproducible technique to devise neuronal networks in vitro with a predefined connectivity induced by the design of the gateway. Daisy-chained neuronal networks with predefined connectivity and functional polarity were produced using the presented micropatterning method. Controlling the direction of signal propagation among populations of neurons provides insights to network communication and offers the chance to investigate more about learning processes in networks by external manipulation of cells and signal cascades. PMID:27379230

  8. Signal Propagation between Neuronal Populations Controlled by Micropatterning.

    PubMed

    Albers, Jonas; Offenhäusser, Andreas

    2016-01-01

    The central nervous system consists of an unfathomable number of functional networks enabling highly sophisticated information processing. Guided neuronal growth with a well-defined connectivity and accompanying polarity is essential for the formation of these networks. To investigate how two-dimensional protein patterns influence neuronal outgrowth with respect to connectivity and functional polarity between adjacent populations of neurons, a microstructured model system was established. Exclusive cell growth on patterned substrates was achieved by transferring a mixture of poly-l-lysine and laminin to a cell-repellent glass surface by microcontact printing. Triangular structures with different opening angle, height, and width were chosen as a pattern to achieve network formation with defined behavior at the junction of adjacent structures. These patterns were populated with dissociated primary cortical embryonic rat neurons and investigated with respect to their impact on neuronal outgrowth by immunofluorescence analysis, as well as their functional connectivity by calcium imaging. Here, we present a highly reproducible technique to devise neuronal networks in vitro with a predefined connectivity induced by the design of the gateway. Daisy-chained neuronal networks with predefined connectivity and functional polarity were produced using the presented micropatterning method. Controlling the direction of signal propagation among populations of neurons provides insights to network communication and offers the chance to investigate more about learning processes in networks by external manipulation of cells and signal cascades. PMID:27379230

  9. Evaluation of Canada goose sterilization for population control.

    USGS Publications Warehouse

    Converse, Kathryn A.; Kennelly, James J.

    1994-01-01

    We evaluated the vasectomy of 72 male Canada geese as a method to control growing populations of nuisance geese in Westchester County, New York. Thirty-three of the vasectomized males paired with a female and were located during ≥1 breeding seasons; 7 treated males were not seen following surgery. The remaining 32 males were never observed paired with a female during the breeding season. Of 56 nesting attempts by the 33 pairs in ≥1 breeding seasons, 84% of the nests were unsuccessful. Fidelity to nest sites during the second and third breeding seasons occurred for 17 of the 18 vasectomized males and their females that were observed for ≥2 seasons. The results suggest that male sterilization may reduce productivity of nuisance Canada geese providing one carefully selects areas and flocks suitable for this type of control.

  10. Control of BRD in large dairy calf populations.

    PubMed

    Lehenbauer, Terry W

    2014-12-01

    Bovine respiratory disease (BRD) is a leading cause of morbidity and mortality in dairy calves. As the number of calves being raised on the dairy farm or at a calf-raising operation has become larger, both opportunity and risk have increased. Opportunities for applying economies of size and scale exist in these large dairy calf populations while meeting specific needs of the dairy calf. BRD control requires effective biosecurity and biocontainment efforts, adequate passive transfer of immunoglobulins, a strategic immunization program, and appropriate diagnostic strategies for ongoing disease surveillance. These components are necessary to achieve an evidence-based approach for preventing and reducing severity of BRD cases. Proper nutrition, housing, and environmental management are important for achieving optimal dairy calf health and performance. Good record keeping and analysis of outcomes are needed to document dairy calf health and performance and to efficiently identify new problems that require attention in these large dairy calf populations. Proper management of calves to prevent and control BRD requires careful planning and follow through to achieve those results but will likely pay big dividends in improved calf health and future productivity. PMID:25497502

  11. Z-type control of populations for Lotka-Volterra model with exponential convergence.

    PubMed

    Zhang, Yunong; Yan, Xiaogang; Liao, Bolin; Zhang, Yinyan; Ding, Yaqiong

    2016-02-01

    The population control of the Lotka-Volterra model is one of the most important and widely investigated issues in mathematical ecology. In this study, assuming that birth rate is controllable and using the Z-type dynamic method, we develop Z-type control laws to drive the prey population and/or predator population to a desired state to keep species away from extinction and to improve ecosystem stability. A direct controller group is initially designed to control the prey and predator populations simultaneously. Two indirect controllers are then proposed for prey population control and predator population control by exerting exogenous measure on another species. All three control laws possess exponential convergence performances. Finally, the corresponding numerical simulations are performed. Results substantiate the theoretical analysis and effectiveness of such Z-type control laws for the population control of the Lotka-Volterra model.

  12. Z-type control of populations for Lotka-Volterra model with exponential convergence.

    PubMed

    Zhang, Yunong; Yan, Xiaogang; Liao, Bolin; Zhang, Yinyan; Ding, Yaqiong

    2016-02-01

    The population control of the Lotka-Volterra model is one of the most important and widely investigated issues in mathematical ecology. In this study, assuming that birth rate is controllable and using the Z-type dynamic method, we develop Z-type control laws to drive the prey population and/or predator population to a desired state to keep species away from extinction and to improve ecosystem stability. A direct controller group is initially designed to control the prey and predator populations simultaneously. Two indirect controllers are then proposed for prey population control and predator population control by exerting exogenous measure on another species. All three control laws possess exponential convergence performances. Finally, the corresponding numerical simulations are performed. Results substantiate the theoretical analysis and effectiveness of such Z-type control laws for the population control of the Lotka-Volterra model. PMID:26644036

  13. Contraceptive vaccines for the humane control of community cat populations.

    PubMed

    Levy, Julie K

    2011-07-01

    Free-roaming unowned stray and feral cats exist throughout the world, creating concerns regarding their welfare as well as their impact on the environment and on public health. Millions of healthy cats are culled each year in an attempt to control their numbers. Surgical sterilization followed by return to the environment is an effective non-lethal population control method but is limited in scope because of expense and logistical impediments. Immunocontraception has the potential to be a more practical and cost-effective method of control. This is a review of current research in immunocontraception in domestic cats. Functional characteristics of an ideal immunocontraceptive for community cats would include a wide margin of safety for target animals and the environment, rapid onset and long duration of activity following a single treatment in males and females of all ages, and sex hormone inhibition. In addition, product characteristics should include stability and ease of use under field conditions, efficient manufacturing process, and low cost to the user. Two reproductive antigens, zona pellucida and GnRH, have been identified as possible targets for fertility control in cats. Zona pellucida, which is used successfully in multiple wildlife species, has achieved little success in cats. In contrast, immunization against GnRH has resulted in long-term contraception in both male and female cats following a single dose. GnRH is an ideal contraceptive target because it regulates pituitary and gonadal hormone responses in both males and females, thus suppressing nuisance behaviors associated with sex hormones in addition to preventing pregnancy. The responsiveness of cats to fertility control via GnRH suppression should encourage researchers and cat control stakeholders to continue efforts to optimize vaccines that induce multiyear contraception following a single dose in a high proportion of treated cats.

  14. Thyroid Function in Women after Multimodal Treatment for Breast Cancer Stage II/III: Comparison With Controls From a Population Sample

    SciTech Connect

    Reinertsen, Kristin Valborg; Cvancarova, Milada; Wist, Erik; Bjoro, Trine; Dahl, Alv A.; Danielsen, Turi; Fossa, Sophie D.

    2009-11-01

    Purpose: A possible association between thyroid diseases (TD) and breast cancer (BC) has been debated. We examined prevalence and development of TD in women after multimodal treatment for Stage II/III BC compared with women from a general population. Secondarily, we explored the impact of two different radiotherapy (RT) techniques (standardized field arrangements vs. computed tomography [CT]-based dose planning) on TD in BC patients examined 35-120 months after primary BC treatment. Methods and Materials: A total of 403 BC patients completed a questionnaire about TD and had blood samples taken for analyses of thyroid function. All had undergone postoperative RT with or without (2%) adjuvant systemic treatment. The results in the BC patients were compared with a cancer-free, age-matched control group from a general population (CGr). Results: There was higher prevalence of self-reported hypothyroidism in the BC patients as compared with the CGr (18% vs. 6%, p < 0.001). The raised prevalence was predominantly due to a substantial increase in the development of hypothyroidism after BC diagnosis, whereas the prevalence of hypothyroidism before BC diagnosis was similar to that observed in the CGr. Patients treated with CT-based RT showed a trend for increased post-BC development of hypothyroidism as compared with those treated with standardized field arrangements (p = 0.08). Conclusions: Hypothyroidism is significantly increased in women after multimodal treatment for Stage II/III BC. Radiation to the thyroid gland may be a contributing factor. BC patients should be routinely screened for hypothyroidism.

  15. [Population dynamics and control techniques of aphids on honeysuckle].

    PubMed

    Sun, Ying; Xue, Ming; Zhang, Xiao; Zhao, Hai-Peng; Li, Zhao-Xia

    2013-11-01

    The objective of this study is to define the population dynamics of Semiaphis heraclei in the main-producing district of Lonicera japonica in Shandong, and screen for highly efficient, safety control technique. Through fixed field investigation, we tested the toxicity of eight kinds of insecticides by using dipping methods, and carried out the field experiment. The results showed that the aphids' emergence peak appeared in May. The aphids on the Sijihua variety of L. japonica was more susceptible and the peak was also seven days earlier than Damao variety of L. japonica. The aphid populations on Sijihua were 1 fold than those on the Daomao in happened peak. Comparing the eight kinds of insecticides, the LC50 of lambda-cyhaothrin, abamectin, imidacloprid and pyrethrin to wingless aphids were 1.494, 1.690, 2.840, 2.861 mg x L(-1), respectively, whose toxicity were higher, the toxicity of matrine, pymetrozine and azadirachtin were also high. The field efficacy trials indicated that during the period of aphids occurred, 25% imidacloprid wettable powder, 1.8% abamectin missible oil, 2.5% lambda-cyhaothrin missible oil, 25% pymetrozine wettable powder, 5% pyrethrin missible oil, 1% matrine water aqua were sprayed at concentrations of 20,000, 2,000, 2,500, 5,000, 500 and 50 times, respectively,the control effect achieved 91.69%, 98.90%, 96.18%, 95.06%, 99.24%, 90.10%, respectively, after 5 days. During the growing period of L. japonica in spring, application of thiamethoxam, thiacloprid, pymetrozine and imidacloprid, all of the control effect against aphids achieved above 98.88% after 50 days. The result indicated that May was the S. heraclei Takahashi's emergence peak in Pingyi, Shandong. The efficient safety and environmentally friendly insecticides by spraying and systemic insecticide of pymetrozine and imidacloprid by root application were all efficient controlled aphids. These insecticides were long for controlling S. heraclei Takahashi and worthy of being widely

  16. [Population dynamics and control techniques of aphids on honeysuckle].

    PubMed

    Sun, Ying; Xue, Ming; Zhang, Xiao; Zhao, Hai-Peng; Li, Zhao-Xia

    2013-11-01

    The objective of this study is to define the population dynamics of Semiaphis heraclei in the main-producing district of Lonicera japonica in Shandong, and screen for highly efficient, safety control technique. Through fixed field investigation, we tested the toxicity of eight kinds of insecticides by using dipping methods, and carried out the field experiment. The results showed that the aphids' emergence peak appeared in May. The aphids on the Sijihua variety of L. japonica was more susceptible and the peak was also seven days earlier than Damao variety of L. japonica. The aphid populations on Sijihua were 1 fold than those on the Daomao in happened peak. Comparing the eight kinds of insecticides, the LC50 of lambda-cyhaothrin, abamectin, imidacloprid and pyrethrin to wingless aphids were 1.494, 1.690, 2.840, 2.861 mg x L(-1), respectively, whose toxicity were higher, the toxicity of matrine, pymetrozine and azadirachtin were also high. The field efficacy trials indicated that during the period of aphids occurred, 25% imidacloprid wettable powder, 1.8% abamectin missible oil, 2.5% lambda-cyhaothrin missible oil, 25% pymetrozine wettable powder, 5% pyrethrin missible oil, 1% matrine water aqua were sprayed at concentrations of 20,000, 2,000, 2,500, 5,000, 500 and 50 times, respectively,the control effect achieved 91.69%, 98.90%, 96.18%, 95.06%, 99.24%, 90.10%, respectively, after 5 days. During the growing period of L. japonica in spring, application of thiamethoxam, thiacloprid, pymetrozine and imidacloprid, all of the control effect against aphids achieved above 98.88% after 50 days. The result indicated that May was the S. heraclei Takahashi's emergence peak in Pingyi, Shandong. The efficient safety and environmentally friendly insecticides by spraying and systemic insecticide of pymetrozine and imidacloprid by root application were all efficient controlled aphids. These insecticides were long for controlling S. heraclei Takahashi and worthy of being widely

  17. 50 CFR 21.61 - Population control of resident Canada geese.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., resumption of injuries caused by growth of the population and not otherwise addressable by the methods... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Population control of resident Canada... Populations § 21.61 Population control of resident Canada geese. (a) Which Canada geese are covered by...

  18. 50 CFR 21.61 - Population control of resident Canada geese.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., resumption of injuries caused by growth of the population and not otherwise addressable by the methods... 50 Wildlife and Fisheries 8 2011-10-01 2011-10-01 false Population control of resident Canada... Populations § 21.61 Population control of resident Canada geese. (a) Which Canada geese are covered by...

  19. 50 CFR 21.61 - Population control of resident Canada geese.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., resumption of injuries caused by growth of the population and not otherwise addressable by the methods... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Population control of resident Canada... Populations § 21.61 Population control of resident Canada geese. (a) Which Canada geese are covered by...

  20. SUPPORT FOR POPULATION LEVEL TOBACCO CONTROL POLICIES IN HUNGARY

    PubMed Central

    Paulik, Edit; Maróti-Nagy, Ágnes; Nagymajtényi, László; Rogers, Todd; Easterling, Doug

    2013-01-01

    SUMMARY Background Smoking is the leading, preventable risk factor for premature death and disability in Hungary. The objective of this paper was to assess the social acceptability of and the predictors of holding favourable attitudes toward tobacco control policies among the Hungarian population. Methods A self-administered questionnaire-based study was carried out among individuals aged 16–70 years. Logistic regression analysis was used to assess whether support for the ten tobacco control policies varies as a function of age, sex, educational level, and smoking status. Results The majority of the respondents supported the studied tobacco control measures. Over 90 percent of the sample supported: fines for retailers selling tobacco products to minors (92.3%), stricter enforcement of restrictions on selling tobacco products to minors (90.5%), and a ban on smoking in health care institutions (91.4%). The lowest levels of support were for bans on sponsorship by the tobacco industry (52.8%) and price increases on tobacco products (54.9%). For each measure, support was significantly lower among smokers than non-smokers. Age and education were significantly related to support for some but not all measures. Conclusions Strong majorities of Hungarians support the enactment and enforcement of a wide range of tobacco control measures, a fact that was acknowledged by Parliament’s passage of the 2011 Anti-Smoking Law. Advocacy efforts to encourage the acceptance of tobacco control policies should focus not only on smokers, but also on younger and less educated non-smokers. PMID:22571024

  1. Rabies and dog population control in Thailand: success or failure?

    PubMed

    Hemachudha, Thiravat

    2005-01-01

    Despite a success in reducing rabies deaths from almost 200 to less than 20 annually, this may not be considered a success. More than 400,000 persons required rabies post-exposure prophylaxis (PEP) in 2003, more than 4 times as many as those in 1991 [93,641 cases in 1991; 183,815 in 1996 and 350,535 in 2001]. The number of samples submitted for testing in rabies diagnostic laboratories has been declining. However, the percent of samples that were confirmed infected with rabies during the 10 year period remained unchanged; within a range of 23 - 30% (MOPH report). Of the 6 million dogs roughly estimated to live in Thailand, there are no reliable data indicating their relative population densities or distribution patterns in various regions throughout the country. However, in a survey conducted by the Bureau of National Statistics and the Bangkok Metropolitan Administration in 1999, it was estimated that approximately 630,000 dogs dwell in Bangkok city (an area of 1 565 sq km). In this survey, approximately 110,000 of the dogs living in Bangkok were considered to be ownerless (stray or feral), whereas the remainder was believed to be owned or were community dogs. Nevertheless, it has not been known how many of the latter group can be accessible or are in compliance with local rabies control regulations. When the dog population statistics collected in 1999 are compared to an earlier survey conducted in 1992, the stray dog population appears to have almost tripled in size in Bangkok over the eight year

  2. Quantifying prion disease penetrance using large population control cohorts.

    PubMed

    Minikel, Eric Vallabh; Vallabh, Sonia M; Lek, Monkol; Estrada, Karol; Samocha, Kaitlin E; Sathirapongsasuti, J Fah; McLean, Cory Y; Tung, Joyce Y; Yu, Linda P C; Gambetti, Pierluigi; Blevins, Janis; Zhang, Shulin; Cohen, Yvonne; Chen, Wei; Yamada, Masahito; Hamaguchi, Tsuyoshi; Sanjo, Nobuo; Mizusawa, Hidehiro; Nakamura, Yosikazu; Kitamoto, Tetsuyuki; Collins, Steven J; Boyd, Alison; Will, Robert G; Knight, Richard; Ponto, Claudia; Zerr, Inga; Kraus, Theo F J; Eigenbrod, Sabina; Giese, Armin; Calero, Miguel; de Pedro-Cuesta, Jesús; Haïk, Stéphane; Laplanche, Jean-Louis; Bouaziz-Amar, Elodie; Brandel, Jean-Philippe; Capellari, Sabina; Parchi, Piero; Poleggi, Anna; Ladogana, Anna; O'Donnell-Luria, Anne H; Karczewski, Konrad J; Marshall, Jamie L; Boehnke, Michael; Laakso, Markku; Mohlke, Karen L; Kähler, Anna; Chambert, Kimberly; McCarroll, Steven; Sullivan, Patrick F; Hultman, Christina M; Purcell, Shaun M; Sklar, Pamela; van der Lee, Sven J; Rozemuller, Annemieke; Jansen, Casper; Hofman, Albert; Kraaij, Robert; van Rooij, Jeroen G J; Ikram, M Arfan; Uitterlinden, André G; van Duijn, Cornelia M; Daly, Mark J; MacArthur, Daniel G

    2016-01-20

    More than 100,000 genetic variants are reported to cause Mendelian disease in humans, but the penetrance-the probability that a carrier of the purported disease-causing genotype will indeed develop the disease-is generally unknown. We assess the impact of variants in the prion protein gene (PRNP) on the risk of prion disease by analyzing 16,025 prion disease cases, 60,706 population control exomes, and 531,575 individuals genotyped by 23andMe Inc. We show that missense variants in PRNP previously reported to be pathogenic are at least 30 times more common in the population than expected on the basis of genetic prion disease prevalence. Although some of this excess can be attributed to benign variants falsely assigned as pathogenic, other variants have genuine effects on disease susceptibility but confer lifetime risks ranging from <0.1 to ~100%. We also show that truncating variants in PRNP have position-dependent effects, with true loss-of-function alleles found in healthy older individuals, a finding that supports the safety of therapeutic suppression of prion protein expression. PMID:26791950

  3. Population-dynamics method with a multicanonical feedback control.

    PubMed

    Nemoto, Takahiro; Bouchet, Freddy; Jack, Robert L; Lecomte, Vivien

    2016-06-01

    We discuss the Giardinà-Kurchan-Peliti population dynamics method for evaluating large deviations of time-averaged quantities in Markov processes [Phys. Rev. Lett. 96, 120603 (2006)PRLTAO0031-900710.1103/PhysRevLett.96.120603]. This method exhibits systematic errors which can be large in some circumstances, particularly for systems with weak noise, with many degrees of freedom, or close to dynamical phase transitions. We show how these errors can be mitigated by introducing control forces within the algorithm. These forces are determined by an iteration-and-feedback scheme, inspired by multicanonical methods in equilibrium sampling. We demonstrate substantially improved results in a simple model, and we discuss potential applications to more complex systems. PMID:27415224

  4. The Left Hand Second to Fourth Digit Ratio (2D:4D) Does Not Discriminate World-Class Female Gymnasts from Age Matched Sedentary Girls

    PubMed Central

    Peeters, Maarten W.; Claessens, Albrecht L.

    2012-01-01

    Introduction The second to fourth-digit-ratio (2D:4D), a putative marker of prenatal androgen action and a sexually dimorphic trait, has been suggested to be related with sports performance, although results are not univocal. If this relation exists, it is most likely to be detected by comparing extreme groups on the continuum of sports performance. Methods In this study the 2D:4D ratio of world-class elite female artistic gymnasts (n = 129), competing at the 1987 Rotterdam World-Championships was compared to the 2D:4D ratio of sedentary age-matched sedentary girls (n = 129), alongside with other anthropometric characteristics including other sexually dimorphic traits such as an androgyny index (Bayer & Bayley) and Heath-Carter somatotype components (endomorphy, mesomorphy, ectomorphy) using AN(C)OVA. 2D:4D was measured on X-rays of the left hand. Results Left hand 2D:4D digit ratio in world class elite female gymnasts (0.921±0.020) did not differ significantly from 2D:4D in age-matched sedentary girls (0.924±0.018), either with or without inclusion of potentially confounding covariates such as skeletal age, height, weight, somatotype components or androgyny index. Height (161.9±6.4 cm vs 155.4±6.6 cm p<0.01), weight (53.9±7.6 kg vs 46.2 6.3 kg p<0.01), BMI (20.51±2.41 kg/m2 vs 19.05±1.56 kg/m2), skeletal age (15.2±1.1 y vs 14.5±1.2 y p>0.01), somatotype components (4.0/3.0/2.9 vs 1.7/3.7/3.2 for endomorphy (p<0.01), mesomorphy (p<0.01) and ectomorphy (p<0.05) respectively) all differed significantly between sedentary girls and elite gymnasts. As expressed by the androgyny index, gymnasts have, on average, broader shoulders relative to their hips, compared to the reference sample. Correlations between the 2D:4D ratio and chronological age, skeletal age, and the anthropometric characteristics are low and not significant. Conclusion Although other anthropometric characteristics of sexual dimorphism were significantly different between the two samples

  5. Costs of children--benefit theory and population control.

    PubMed

    Tian, X

    1989-01-01

    fertile women are also important. The State's population policy of rewards and penalties also affects the costs and benefits. Administrative intervention to implement the FP program have been effectively and adequately used in the past to control population growth, even though it is recognized that social and economic development is another way of affecting population growth. Parents still need to be guaranteed that 1 child will indeed be a benefit. Children's economic value has been accepted, and policy is moving in the direction of correcting the imbalances between children's costs and benefits, such as increasing fines along with improving education and income distribution.

  6. Control of mucosal polymicrobial populations by innate immunity.

    PubMed

    Mason, Katie L; Huffnagle, Gary B

    2009-09-01

    The gastrointestinal tract carries out the complex process of localizing the polymicrobial populations of the indigenous microbiota to the lumenal side of the GI mucosa while absorbing nutrients from the lumen and preventing damage to the mucosa. This process is accomplished through a combination of physical, innate and adaptive host defences and a 'strategic alliance' with members of the microbiota. To cope with the constant exposure to a diverse microbial community, the GI tract, through the actions of a number of specialized cells in the epithelium and lamina propria, has layers of humoral, physical and cellular defences that limit attachment, invasion and dissemination of the indigenous microbiota. However, the role of the microbiota in this dynamic balance is vital and serves as another level of 'innate' defence. We are just beginning to understand how bacterial metabolites aid in the control of potential pathogens within the microbiota and limit inflammatory responses to the microbiota, concepts that will impact our understanding of the biological effects of antibiotics, diet and probiotics on mucosal inflammatory responses. PMID:19558617

  7. Expression of Phenotypic Astrocyte Marker Is Increased in a Transgenic Mouse Model of Alzheimer's Disease versus Age-Matched Controls: A Presymptomatic Stage Study

    PubMed Central

    Doméné, Aurélie; Cavanagh, Chelsea; Page, Guylène; Bodard, Sylvie; Klein, Christophe; Delarasse, Cécile; Chalon, Sylvie

    2016-01-01

    Recent mouse studies of the presymptomatic stage of Alzheimer's disease (AD) have suggested that proinflammatory changes, such as glial activation and cytokine induction, may occur already at this early stage through unknown mechanisms. Because TNFα contributes to increased Aβ production from the Aβ precursor protein (APP), we assessed a putative correlation between APP/Aβ and TNFα during the presymptomatic stage as well as early astrocyte activation in the hippocampus of 3-month-old APPswe/PS1dE9 mice. While Western blots revealed significant APP expression, Aβ was not detectable by Western blot or ELISA attesting that 3-month-old, APPswe/PS1dE9 mice are at a presymptomatic stage of AD-like pathology. Western blots were also used to show increased GFAP expression in transgenic mice that positively correlated with both TNFα and APP, which were also mutually correlated. Subregional immunohistochemical quantification of phenotypic (GFAP) and functional (TSPO) markers of astrocyte activation indicated a selective and significant increase in GFAP-immunoreactive (IR) cells in the dentate gyrus of APPswe/PS1dE9 mice. Our data suggest that subtle morphological and phenotypic alterations, compatible with the engagement of astrocyte along the activation pathway, occur in the hippocampus already at the presymptomatic stage of AD. PMID:27672476

  8. Comparing the PPAT Drawings of Boys with AD/HD and Age-Matched Controls Using the Formal Elements Art Therapy Scale.

    ERIC Educational Resources Information Center

    Munley, Maripat

    2002-01-01

    Explores whether children with AD/HD respond differently to a specific art directive. Using the Formal Elements Art Therapy Scale to evaluate the drawings, results indicate three elements that would most accurately predict the artists into the AD/HD group: color prominence, details of objects and environments, and line quality. (Contains 29…

  9. Processing Words Varying in Personal Familiarity (Based on Reading and Spelling) by Poor Readers and Age-Matched and Reading-Matched Controls

    ERIC Educational Resources Information Center

    Corcos, Evelyne; Willows, Dale M.

    2009-01-01

    To evaluate whether performance differences between good and poor readers relate to reading-specific cognitive factors that result from engaging in reading activities and other experiential factors, the authors gave students in Grades 4 and 6 a perceptual identification test of words not only drawn from their personal lexicon but also varying in…

  10. Expression of Phenotypic Astrocyte Marker Is Increased in a Transgenic Mouse Model of Alzheimer's Disease versus Age-Matched Controls: A Presymptomatic Stage Study

    PubMed Central

    Doméné, Aurélie; Cavanagh, Chelsea; Page, Guylène; Bodard, Sylvie; Klein, Christophe; Delarasse, Cécile; Chalon, Sylvie

    2016-01-01

    Recent mouse studies of the presymptomatic stage of Alzheimer's disease (AD) have suggested that proinflammatory changes, such as glial activation and cytokine induction, may occur already at this early stage through unknown mechanisms. Because TNFα contributes to increased Aβ production from the Aβ precursor protein (APP), we assessed a putative correlation between APP/Aβ and TNFα during the presymptomatic stage as well as early astrocyte activation in the hippocampus of 3-month-old APPswe/PS1dE9 mice. While Western blots revealed significant APP expression, Aβ was not detectable by Western blot or ELISA attesting that 3-month-old, APPswe/PS1dE9 mice are at a presymptomatic stage of AD-like pathology. Western blots were also used to show increased GFAP expression in transgenic mice that positively correlated with both TNFα and APP, which were also mutually correlated. Subregional immunohistochemical quantification of phenotypic (GFAP) and functional (TSPO) markers of astrocyte activation indicated a selective and significant increase in GFAP-immunoreactive (IR) cells in the dentate gyrus of APPswe/PS1dE9 mice. Our data suggest that subtle morphological and phenotypic alterations, compatible with the engagement of astrocyte along the activation pathway, occur in the hippocampus already at the presymptomatic stage of AD.

  11. Expression of Phenotypic Astrocyte Marker Is Increased in a Transgenic Mouse Model of Alzheimer's Disease versus Age-Matched Controls: A Presymptomatic Stage Study.

    PubMed

    Doméné, Aurélie; Cavanagh, Chelsea; Page, Guylène; Bodard, Sylvie; Klein, Christophe; Delarasse, Cécile; Chalon, Sylvie; Krantic, Slavica

    2016-01-01

    Recent mouse studies of the presymptomatic stage of Alzheimer's disease (AD) have suggested that proinflammatory changes, such as glial activation and cytokine induction, may occur already at this early stage through unknown mechanisms. Because TNFα contributes to increased Aβ production from the Aβ precursor protein (APP), we assessed a putative correlation between APP/Aβ and TNFα during the presymptomatic stage as well as early astrocyte activation in the hippocampus of 3-month-old APPswe/PS1dE9 mice. While Western blots revealed significant APP expression, Aβ was not detectable by Western blot or ELISA attesting that 3-month-old, APPswe/PS1dE9 mice are at a presymptomatic stage of AD-like pathology. Western blots were also used to show increased GFAP expression in transgenic mice that positively correlated with both TNFα and APP, which were also mutually correlated. Subregional immunohistochemical quantification of phenotypic (GFAP) and functional (TSPO) markers of astrocyte activation indicated a selective and significant increase in GFAP-immunoreactive (IR) cells in the dentate gyrus of APPswe/PS1dE9 mice. Our data suggest that subtle morphological and phenotypic alterations, compatible with the engagement of astrocyte along the activation pathway, occur in the hippocampus already at the presymptomatic stage of AD. PMID:27672476

  12. Analyzing Population Genetics Using the Mitochondrial Control Region and Bioinformatics

    ERIC Educational Resources Information Center

    Sato, Takumi; Phillips, Bonnie; Latourelle, Sandra M.; Elwess, Nancy L.

    2010-01-01

    The 14-base pair hypervariable region in mitochondrial DNA (mtDNA) of Asian populations, specifically Japanese and Chinese students at Plattsburgh State University, was examined. Previous research on this 14-base pair region showed it to be susceptible to mutations and as a result indicated direct correlation with specific ethnic populations.…

  13. Ecological feedbacks can reduce population-level efficacy of wildlife fertility control

    PubMed Central

    Ransom, Jason I; Powers, Jenny G; Thompson Hobbs, N; Baker, Dan L

    2014-01-01

    Anthropogenic stress on natural systems, particularly the fragmentation of landscapes and the extirpation of predators from food webs, has intensified the need to regulate abundance of wildlife populations with management. Controlling population growth using fertility control has been considered for almost four decades, but nearly all research has focused on understanding effects of fertility control agents on individual animals. Questions about the efficacy of fertility control as a way to control populations remain largely unanswered. Collateral consequences of contraception can produce unexpected changes in birth rates, survival, immigration and emigration that may reduce the effectiveness of regulating animal abundance. The magnitude and frequency of such effects vary with species-specific social and reproductive systems, as well as connectivity of populations. Developing models that incorporate static demographic parameters from populations not controlled by contraception may bias predictions of fertility control efficacy. Many population-level studies demonstrate that changes in survival and immigration induced by fertility control can compensate for the reduction in births caused by contraception. The most successful cases of regulating populations using fertility control come from applications of contraceptives to small, closed populations of gregarious and easily accessed species. Fertility control can result in artificial selection pressures on the population and may lead to long-term unintentional genetic consequences. The magnitude of such selection is dependent on individual heritability and behavioural traits, as well as environmental variation. Synthesis and applications. Understanding species' life-history strategies, biology, behavioural ecology and ecological context is critical to developing realistic expectations of regulating populations using fertility control. Before time, effort and funding are invested in wildlife contraception, managers

  14. Ecological feedbacks can reduce population-level efficacy of wildlife fertility control

    USGS Publications Warehouse

    Ransom, Jason I.; Powers, Jenny G.; Hobbs, N. Thompson; Baker, Dan L.

    2014-01-01

    1. Anthropogenic stress on natural systems, particularly the fragmentation of landscapes and the extirpation of predators from food webs, has intensified the need to regulate abundance of wildlife populations with management. Controlling population growth using fertility control has been considered for almost four decades, but nearly all research has focused on understanding effects of fertility control agents on individual animals. Questions about the efficacy of fertility control as a way to control populations remain largely unanswered. 2. Collateral consequences of contraception can produce unexpected changes in birth rates, survival, immigration and emigration that may reduce the effectiveness of regulating animal abundance. The magnitude and frequency of such effects vary with species-specific social and reproductive systems, as well as connectivity of populations. Developing models that incorporate static demographic parameters from populations not controlled by contraception may bias predictions of fertility control efficacy. 3. Many population-level studies demonstrate that changes in survival and immigration induced by fertility control can compensate for the reduction in births caused by contraception. The most successful cases of regulating populations using fertility control come from applications of contraceptives to small, closed populations of gregarious and easily accessed species. 4. Fertility control can result in artificial selection pressures on the population and may lead to long-term unintentional genetic consequences. The magnitude of such selection is dependent on individual heritability and behavioural traits, as well as environmental variation. 5. Synthesis and applications. Understanding species' life-history strategies, biology, behavioural ecology and ecological context is critical to developing realistic expectations of regulating populations using fertility control. Before time, effort and funding are invested in wildlife

  15. Investigating Biological Control Agents for Controlling Invasive Populations of the Mealybug Pseudococcus comstocki in France.

    PubMed

    Malausa, Thibaut; Delaunay, Mathilde; Fleisch, Alexandre; Groussier-Bout, Géraldine; Warot, Sylvie; Crochard, Didier; Guerrieri, Emilio; Delvare, Gérard; Pellizzari, Giuseppina; Kaydan, M Bora; Al-Khateeb, Nadia; Germain, Jean-François; Brancaccio, Lisa; Le Goff, Isabelle; Bessac, Melissa; Ris, Nicolas; Kreiter, Philippe

    2016-01-01

    Pseudococcus comstocki (Hemiptera: Pseudococcidae) is a mealybug species native to Eastern Asia and present as an invasive pest in northern Italy and southern France since the start of the century. It infests apple and pear trees, grapevines and some ornamental trees. Biocontrol programmes against this pest proved successful in central Asia and North America in the second half of the 20th century. In this study, we investigated possible biocontrol agents against P. comstocki, with the aim of developing a biocontrol programme in France. We carried out systematic DNA-barcoding at each step in the search for a specialist parasitoid. First we characterised the French target populations of P. comstocki. We then identified the parasitoids attacking P. comstocki in France. Finally, we searched for foreign mealybug populations identified a priori as P. comstocki and surveyed their hymenopteran parasitoids. Three mealybug species (P. comstocki, P. viburni and P. cryptus) were identified during the survey, together with at least 16 different parasitoid taxa. We selected candidate biological control agent populations for use against P. comstocki in France, from the species Allotropa burrelli (Hymenoptera: Platygastridae) and Acerophagus malinus (Hymenoptera: Encyrtidae). The coupling of molecular and morphological characterisation for both pests and natural enemies facilitated the programme development and the rejection of unsuitable or generalist parasitoids. PMID:27362639

  16. Investigating Biological Control Agents for Controlling Invasive Populations of the Mealybug Pseudococcus comstocki in France

    PubMed Central

    Malausa, Thibaut; Delaunay, Mathilde; Fleisch, Alexandre; Groussier-Bout, Géraldine; Warot, Sylvie; Crochard, Didier; Guerrieri, Emilio; Delvare, Gérard; Pellizzari, Giuseppina; Kaydan, M. Bora; Al-Khateeb, Nadia; Germain, Jean-François; Brancaccio, Lisa; Le Goff, Isabelle; Bessac, Melissa; Ris, Nicolas; Kreiter, Philippe

    2016-01-01

    Pseudococcus comstocki (Hemiptera: Pseudococcidae) is a mealybug species native to Eastern Asia and present as an invasive pest in northern Italy and southern France since the start of the century. It infests apple and pear trees, grapevines and some ornamental trees. Biocontrol programmes against this pest proved successful in central Asia and North America in the second half of the 20th century. In this study, we investigated possible biocontrol agents against P. comstocki, with the aim of developing a biocontrol programme in France. We carried out systematic DNA-barcoding at each step in the search for a specialist parasitoid. First we characterised the French target populations of P. comstocki. We then identified the parasitoids attacking P. comstocki in France. Finally, we searched for foreign mealybug populations identified a priori as P. comstocki and surveyed their hymenopteran parasitoids. Three mealybug species (P. comstocki, P. viburni and P. cryptus) were identified during the survey, together with at least 16 different parasitoid taxa. We selected candidate biological control agent populations for use against P. comstocki in France, from the species Allotropa burrelli (Hymenoptera: Platygastridae) and Acerophagus malinus (Hymenoptera: Encyrtidae). The coupling of molecular and morphological characterisation for both pests and natural enemies facilitated the programme development and the rejection of unsuitable or generalist parasitoids. PMID:27362639

  17. The organization and control of an evolving interdependent population

    PubMed Central

    Vural, Dervis C.; Isakov, Alexander; Mahadevan, L.

    2015-01-01

    Starting with Darwin, biologists have asked how populations evolve from a low fitness state that is evolutionarily stable to a high fitness state that is not. Specifically of interest is the emergence of cooperation and multicellularity where the fitness of individuals often appears in conflict with that of the population. Theories of social evolution and evolutionary game theory have produced a number of fruitful results employing two-state two-body frameworks. In this study, we depart from this tradition and instead consider a multi-player, multi-state evolutionary game, in which the fitness of an agent is determined by its relationship to an arbitrary number of other agents. We show that populations organize themselves in one of four distinct phases of interdependence depending on one parameter, selection strength. Some of these phases involve the formation of specialized large-scale structures. We then describe how the evolution of independence can be manipulated through various external perturbations. PMID:26040593

  18. The organization and control of an evolving interdependent population.

    PubMed

    Vural, Dervis C; Isakov, Alexander; Mahadevan, L

    2015-07-01

    Starting with Darwin, biologists have asked how populations evolve from a low fitness state that is evolutionarily stable to a high fitness state that is not. Specifically of interest is the emergence of cooperation and multicellularity where the fitness of individuals often appears in conflict with that of the population. Theories of social evolution and evolutionary game theory have produced a number of fruitful results employing two-state two-body frameworks. In this study, we depart from this tradition and instead consider a multi-player, multi-state evolutionary game, in which the fitness of an agent is determined by its relationship to an arbitrary number of other agents. We show that populations organize themselves in one of four distinct phases of interdependence depending on one parameter, selection strength. Some of these phases involve the formation of specialized large-scale structures. We then describe how the evolution of independence can be manipulated through various external perturbations.

  19. Conference on Geospatial Approaches to Cancer Control and Population Sciences

    Cancer.gov

    The purpose of this conference is to bring together a community of researchers across the cancer control continuum using geospatial tools, models and approaches to address cancer prevention and control.

  20. The rapid reproducers paradox: population control and individual procreative rights.

    PubMed

    Wissenburg, M

    1998-01-01

    This article argues that population policies need to be evaluated from macro and micro perspectives and to consider individual rights. Ecological arguments that are stringent conditions of liberal democracy are assessed against a moral standard. The moral standard is applied to a series of reasons for limiting procreative rights in the cause of sustainability. The focus is directly on legally enforced antinatalist measures and not on indirect policies with incentives and disincentives. The explicit assumption is that population policy violates the fairness to individuals for societal gain and that population policies are incompatible with stringent conditions of liberal democracy. The author identifies the individual-societal tradeoff as the "rapid reproducers paradox." The perfect sustainable population level is either not possible or is a repugnant alternative. 12 ecological arguments are presented, and none are found compatible with notions of a liberal democracy. Three alternative antinatalist options are the acceptance of less rigid and still coercive policies, amendments to the conception of liberal democracy, or loss of hope and choice of noncoercive solutions to sustainability, none of which is found viable. If voluntary abstinence and distributive solutions fail, then frugal demand options and technological supply options both will be necessary.

  1. Environmental Pollution Control: Two Views from the General Population

    ERIC Educational Resources Information Center

    Althoff, Phillip; Greig, William H.

    1977-01-01

    Citizens exhibitied concern about pollution, a low level of trust in governmental and industrial efforts, and a low level of dedication to environmental protection. Demands to clean up the environment came from one segment of the population while demands to solve the energy crisis came from other segments. (AJ)

  2. [Population].

    PubMed

    1979-01-01

    Data on the population of Venezuela between 1975 and 1977 are presented in descriptive tables and graphs. Information is included on the employed population according to category, sex, and type of economic activity, and by sex, age, and area on the employment rate and the total, the economically active, and the unemployed population.

  3. 50 CFR 31.2 - Methods of surplus wildlife population control and disposal.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Methods of surplus wildlife population control and disposal. 31.2 Section 31.2 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE... Surplus Wildlife § 31.2 Methods of surplus wildlife population control and disposal. Upon a...

  4. 50 CFR 31.2 - Methods of surplus wildlife population control and disposal.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Methods of surplus wildlife population control and disposal. 31.2 Section 31.2 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE... Surplus Wildlife § 31.2 Methods of surplus wildlife population control and disposal. Upon a...

  5. 50 CFR 31.2 - Methods of surplus wildlife population control and disposal.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Methods of surplus wildlife population control and disposal. 31.2 Section 31.2 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE... Surplus Wildlife § 31.2 Methods of surplus wildlife population control and disposal. Upon a...

  6. 50 CFR 31.2 - Methods of surplus wildlife population control and disposal.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 8 2011-10-01 2011-10-01 false Methods of surplus wildlife population control and disposal. 31.2 Section 31.2 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE... Surplus Wildlife § 31.2 Methods of surplus wildlife population control and disposal. Upon a...

  7. 50 CFR 31.2 - Methods of surplus wildlife population control and disposal.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 9 2012-10-01 2012-10-01 false Methods of surplus wildlife population control and disposal. 31.2 Section 31.2 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE... Surplus Wildlife § 31.2 Methods of surplus wildlife population control and disposal. Upon a...

  8. Large-scale control site selection for population monitoring: an example assessing Sage-grouse trends

    USGS Publications Warehouse

    Fedy, Bradley C.; O'Donnell, Michael; Bowen, Zachary H.

    2015-01-01

    Human impacts on wildlife populations are widespread and prolific and understanding wildlife responses to human impacts is a fundamental component of wildlife management. The first step to understanding wildlife responses is the documentation of changes in wildlife population parameters, such as population size. Meaningful assessment of population changes in potentially impacted sites requires the establishment of monitoring at similar, nonimpacted, control sites. However, it is often difficult to identify appropriate control sites in wildlife populations. We demonstrated use of Geographic Information System (GIS) data across large spatial scales to select biologically relevant control sites for population monitoring. Greater sage-grouse (Centrocercus urophasianus; hearafter, sage-grouse) are negatively affected by energy development, and monitoring of sage-grouse population within energy development areas is necessary to detect population-level responses. Weused population data (1995–2012) from an energy development area in Wyoming, USA, the Atlantic Rim Project Area (ARPA), and GIS data to identify control sites that were not impacted by energy development for population monitoring. Control sites were surrounded by similar habitat and were within similar climate areas to the ARPA. We developed nonlinear trend models for both the ARPA and control sites and compared long-term trends from the 2 areas. We found little difference between the ARPA and control sites trends over time. This research demonstrated an approach for control site selection across large landscapes and can be used as a template for similar impact-monitoring studies. It is important to note that identification of changes in population parameters between control and treatment sites is only the first step in understanding the mechanisms that underlie those changes. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

  9. Population.

    ERIC Educational Resources Information Center

    International Planned Parenthood Federation, London (England).

    In an effort to help meet the growing interest and concern about the problems created by the rapid growth of population, The International Planned Parenthood Federation has prepared this booklet with the aim of assisting the study of the history and future trends of population growth and its impact on individual and family welfare, national,…

  10. A review of perioperative glucose control in the neurosurgical population.

    PubMed

    Atkins, Joshua H; Smith, David S

    2009-11-01

    Significant fluctuations in serum glucose levels accompany the stress response of surgery or acute injury and may be associated with vascular or neurologic morbidity. Maintenance of euglycemia with intensive insulin therapy (IIT) continues to be investigated as a therapeutic intervention to decrease morbidity associated with derangements in glucose metabolism. Hypoglycemia is a common side effect of IIT with potential for significant morbidity, especially in the neurologically injured patient. Differences in cerebral versus systemic glucose metabolism, the time course of cerebral response to injury, and heterogeneity of pathophysiology in neurosurgical patient populations are important to consider in evaluating the risks and benefits of IIT. While extremes of glucose levels are to be avoided, there are little data to support specific use of IIT for maintenance of euglycemia in the perioperative management of neurosurgical patients. Existing data are summarized and reviewed in this context. PMID:20144389

  11. Economic benefit of fertility control in wild horse populations

    USGS Publications Warehouse

    Bartholow, J.

    2007-01-01

    I projected costs for several contraceptive treatments that could be used by the Bureau of Land Management (BLM) to manage 4 wild horse (Equus caballus) populations. Potential management alternatives included existing roundup and selective removal methods combined with contraceptives of different duration and effectiveness. I projected costs for a 20-year economic life using the WinEquus?? wild horse population model and state-by-state cost estimates reflecting BLM's operational expenses. Findings revealed that 1) currently available 2-year contraceptives in most situations are capable of reducing variable operating costs by 15%, 2) experimental 3-year contraceptives may be capable of reducing costs by 18%, and 3) combining contraceptives with modest changes to herd sex ratio (e.g., 55-60% M) could trim costs by 30%. Predicted savings can increase when contraception is applied in conjunction with a removal policy that targets horses aged 0-4 years instead of 0-5 years. However, reductions in herd size result in greater variation in annual operating expenses. Because the horse program's variable operating costs make up about half of the total program costs (which include other fixed costs), contraceptive application and management can only reduce total costs by 14%, saving about $6.1 million per year. None of the contraceptive options I examined eliminated the need for long-term holding facilities over the 20-year period simulated, but the number of horses held may be reduced by about 17% with contraceptive treatment. Cost estimates were most sensitive to the oldest age adoptable and per-day holding costs. The BLM will experience significant cost savings as carefully designed contraceptive programs become widespread in the wild horse herds it manages.

  12. Hydrological Controls on Water Chemistry that Supports Freshwater Mussel Populations

    NASA Astrophysics Data System (ADS)

    Prestegaard, K. L.

    2012-12-01

    Native freshwater mussel species ranges and population sizes have been declining throughout N. America. Due to their sedentary nature, adult mussels are vulnerable to both local habitat changes (often associated with land-use changes, contaminants, and biological invaders) and to climate changes that can alter river flow regimes, bed stability, and water chemistry. The purpose of this study is to examine the relationship between water chemistry and hydrological events in rivers that support native mussel populations. USGS ion concentration and water quality (pH, temperature, conductivity) data were used to calculate saturation indices for aragonite. For some sites, electrical conductivity was highly correlated with calcium and bicarbonate concentrations and could be used to estimate concentrations when ion chemistry was not measured. Continuous water quality data from datasondes could thus be used to evaluate saturation indices for aragonite on a daily basis for 10-15 year periods. For the Delaware River, which has relatively few carbonate rocks in its watershed, tributary aragonite saturation tended to reflect local geological conditions. The lower main stem of the river integrates the water chemistry of the basin and also responds to climatic conditions. The lower Delaware supports aragonite precipitation approximately 50 days per year, with considerable inter-annual variability. During most years, aragonite precipitation could occur during both the spring and late summer periods, but years with heavy spring rains rather than snowmelt shifts aragonite precipitation to late summer periods. In 2011 when several major tropical storms hit the Delaware basin, streamflow was too dilute for aragonite precipitation for most of the summer period. These data suggest that hydrological changes associated with climatic changes may influence the water chemistry and affect the suitability of some rivers as mussel habitat.

  13. Control of pestivirus infections in the management of wildlife populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The lack of host-specificity allow pestiviruses to infect domestic livestock as well as captive and free-ranging wildlife, posing unique challenges to different stakeholders. While current control measures for bovine viral diarrhea virus (BVDV) are focused only on cattle, increased attention on the ...

  14. Role of pyrethroids in control of malaria amongst refugee population.

    PubMed

    Jamali, Seemin

    2011-05-01

    Malaria is a human disease caused by sporozoan parasite belonging to genus plasmodium. According to World Health Organization (WHO) estimates for year 2006, there were 247 million clinical infections and 0.88 million deaths due to malaria. Malaria control programmes aim to contain the disease and reduce its' burden on the refugees by adopting various methods to reduce the incidence of malaria by targeting the mosquitos. Most of the displaced people live in Asia and Africa, where host countries lack the resources to support them. Under these conditions, the methods adopted for control of malaria should be both effective and safe. Pyrethroids form the mainstay of preventive measures due to their efficacy and safety in mammals. They can be used as (a) indoor residual sprays, (b) impregnation of bednets, blankets/top sheets, curtains and personal clothing, (c) pyrethroid containing coils, mats and vaporizers and (d) livestock sponging. PMID:22204186

  15. Biomineralization control related to population density under ocean acidification

    NASA Astrophysics Data System (ADS)

    Goffredo, Stefano; Prada, Fiorella; Caroselli, Erik; Capaccioni, Bruno; Zaccanti, Francesco; Pasquini, Luca; Fantazzini, Paola; Fermani, Simona; Reggi, Michela; Levy, Oren; Fabricius, Katharina E.; Dubinsky, Zvy; Falini, Giuseppe

    2014-07-01

    Anthropogenic CO2 is a major driver of present environmental change in most ecosystems, and the related ocean acidification is threatening marine biota. With increasing pCO2, calcification rates of several species decrease, although cases of upregulation are observed. Here, we show that biological control over mineralization relates to species abundance along a natural pH gradient. As pCO2 increased, the mineralogy of a scleractinian coral (Balanophyllia europaea) and a mollusc (Vermetus triqueter) did not change. In contrast, two calcifying algae (Padina pavonica and Acetabularia acetabulum) reduced and changed mineralization with increasing pCO2, from aragonite to the less soluble calcium sulphates and whewellite, respectively. As pCO2 increased, the coral and mollusc abundance was severely reduced, with both species disappearing at pH < 7.8. Conversely, the two calcifying and a non-calcifying algae (Lobophora variegata) showed less severe or no reductions with increasing pCO2, and were all found at the lowest pH site. The mineralization response to decreasing pH suggests a link with the degree of control over the biomineralization process by the organism, as only species with lower control managed to thrive in the lowest pH.

  16. Biomineralization control related to population density under ocean acidification

    PubMed Central

    Goffredo, Stefano; Prada, Fiorella; Caroselli, Erik; Capaccioni, Bruno; Zaccanti, Francesco; Pasquini, Luca; Fantazzini, Paola; Fermani, Simona; Reggi, Michela; Levy, Oren; Fabricius, Katharina E.; Dubinsky, Zvy; Falini, Giuseppe

    2014-01-01

    Anthropogenic CO2 is a major driver of current environmental change in most ecosystems1, and the related ocean acidification (OA) is threatening marine biota2. With increasing pCO2, calcification rates of several species decrease3, although cases of up-regulation are observed4. Here, we show that biological control over mineralization relates to species abundance along a natural pH gradient. As pCO2 increased, the mineralogy of a scleractinian coral (Balanophyllia europaea) and a mollusc (Vermetus triqueter) did not change. In contrast, two calcifying algae (Padina pavonica and Acetabularia acetabulum) reduced and changed mineralization with increasing pCO2, from aragonite to the less soluble calcium sulphates and whewellite, respectively. As pCO2 increased, the coral and mollusc abundance was severely reduced, with both species disappearing at pH < 7.8. Conversely, the two calcifying and a non-calcifying algae (Lobophora variegata) showed less severe or no reductions with increasing pCO2, and were all found at the lowest pH site. The mineralization response to decreasing pH suggests a link with the degree of control over the biomineralization process by the organism, as only species with lower control managed to thrive in the lowest pH. PMID:25071869

  17. [Beijing to use education, incentives to control population growth].

    PubMed

    1979-11-01

    The Beijing Municipal Family Planning Office started in 1979 a "1 child-1 family" campaign aimed at city dwellers and suburban peasants through a system of incentives for parents. The aim is to reduce China's population growth to 5/1000 by 1985. Parents who undertake to have only 1 child will receive a certificate entitling the child to preferential entrance to nursery school, kindergarten, school, factory jobs, and preferential treatment in medical care. A 1 child family will receive an annual 60 yuan bonus to be returned if the parents decide to have another child. Better housing and less taxation will also be provided for 1 child families. Childless people will receive their full wage as a pension on retirement, or will receive subsidies from their production team. A series of measures to improve maternity and child care, and sterilization operations have also been taken. An education campaign to change ideas about male superiority is presently taking place in rural areas, and young couples are recommended to move in with the bride's family.

  18. Control and management of insect populations by chemosterilants.

    PubMed Central

    Borkovec, A B

    1976-01-01

    Chemosterilants, i.e., chemical compounds that interfere with the reproduction potential of sexually reproducing organisms, can be used in three new approaches to insect control. In the sterile-insect release technique, the principal problem is to develop compounds and methods for their application that would not result in introducing harmful residues into the environment. Because of the unusual and often unique circumstances connected with releasing large numbers of sterilized insects, the residue problem and its cost-benefit aspects must be examined individually for each intended control or eradication program. In the direct application technique, chemosterilants must meet the same efficiency and safety standards required from approved insecticides. Combined insecticidal and sterilizing activity is characteristic for some compounds now being investigated. In the genetic technique, chemosterilants may be used for inducing heritable changes in the insect's genome under laboratory conditions, and such procedures would not present any residue problems. Only the first two chemosterilant techniques are approaching practical application, and their safety aspects require detailed evaluation and assessment. PMID:789057

  19. [Is it necessary to control the population growth of national minorities].

    PubMed

    Tian, X Y

    1981-02-01

    In the process of Socialist construction and modernization, the development of the population of national minorities deserves our attention because it is directly related to the economic and cultural development in the areas inhabited by such national minorities, and it has a great impact on the welfare and future of those people. Moreover, the population growth of the minorities is a key factor in the national population control strategy. A rapid population growth among the minorities has caused serious problems in distribution of farm land and food supply, low personal income, a rise in the unemployment rate, and a rise in the illiteracy rate. This has prevented a rise in the living standard among the minority population. In order to prevent and solve population problems among the minorities, we must take appropriate measures according to local conditions to control population increases. Through popularization of education, population growth may be put under control. For those people who volunteer to practice family planning, the government should provide all kinds of assistance. At the same time, an effort is needed to introduce the necessity of improving birth quality, to popularize new methods of child birth, and to develop health and medical care for the general public, so that the quality of the minority population may be gradually improved.

  20. Medicine and health care along the Silk Road. China's population control program among the national minorities.

    PubMed

    Cheng, T O

    1985-01-01

    Travel along the Silk Road where many of China's national minorities live gives a new insight into the population growth problem. As a whole China's "one-child-for-one-family" campaign seems to have succeeded in controlling its national population, although the government takes a more liberal attitude toward the national minorities.

  1. Randomized-Control Screening Trials to Lower Gall Bladder Cancer Mortality in High Risk Populations.

    PubMed

    Krishnatreya, Manigreeva; Kataki, Amal Chandra

    2016-01-01

    Gall bladder cancer is generally fatal. The high morbidity and mortality due to gall bladder cancer exerts a significant impact on efforts towards cancer control in high risk populations of the World and a rationale program for control of gall bladder cancer mortality has remained as an unmet need in these populations. Currently there are no effective strategies for controlling gall bladder cancer mortality. This mini review is to highlight the need and feasibility for secondary prevention of gall bladder cancer by screening in high risk populations. A way forward is to assess the role of secondary prevention of gall bladder cancers by conducting randomized- controlled screening trials in high risk populations. PMID:27221939

  2. Migratory bird hunter opinions regarding potential management strategies for controlling light goose populations

    USGS Publications Warehouse

    Dinges, Andrew J.; Webb, Elisabeth B.; Vrtiska, Mark P.; Nilon, Charles H.; Wilhelm Stanis, Sonja A.

    2014-01-01

    We expanded the Nebraska Light Goose Conservation Order (LGCO) harvest survey (NE, USA) in spring 2012 to assess migratory bird hunter opinions regarding future management strategies for controlling light goose populations. Although hunters strongly agreed that population control of light geese was an important wildlife management issue, they were generally unsupportive of wildlife officials using forms of direct control methods to control light goose populations. Respondents who indicated participation in the 2012 LGCO were also less supportive of any form of direct control compared with migratory bird hunters who did not participate in the LGCO. When presented with alternative methods by wildlife officials for future light goose population control, respondents were most supportive of wildlife agencies selectively shooting light geese on migration and wintering areas and least supportive of wildlife officials using bait with approved chemicals to euthanize light geese. A clear understanding of public perception of various potential direct-control options will likely assist wildlife biologists in making informed decisions on how to proceed with population control of light geese.

  3. Evaluation of demographic parameters of native rodent populations and implications for control

    PubMed Central

    French, Norman R.

    1975-01-01

    The ecology of the multimammate mouse ,Mastomys natalensis, is reviewed and approximations are derived for the parameters governing population growth. By means of computer simulation, the relative importance of the timing of reproduction, the age class distribution or age structure of the population, the competition between Mastomys and Rattus, and the interaction with a predator are evaluated. Although each of these demographic or ecological factors modifies the fate of the Mastomys population, the greatest single impact results from a reproductive season that is divided into two parts rather than a single continuous reproductive season. Division into two parts, correlated with a similar distribution of rainfall, allows time for maturing of the young born early in the season and for production of young by them, thus adding to the momentum of population increase. The interaction of density-dependent factors controlling population growth, competition with another rodent, or predation by a Viverrid predator, may increase the growth rate of the Mastomys population or may depress population growth rate, even to the point of extinction. These simulation studies demonstrate the necessity for critical evaluation of the demographic parameters and ecological characteristics of a particular Mastomys population before an effective control programme can be designed. They also demonstrate, however, that if the programme is based upon sound ecological theory control can be effected. PMID:1085223

  4. Toxoplasmosis gondii and schizophrenia: a case control study in a low Toxoplasma gondii seroprevalence Mexican population

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There are conflicting reports concerning the association of T. gondii infection and schizophrenia. Therefore, we determined such association in a Mexican population of Mestizo ethnicity. Through a case-control study design, 50 schizophrenic patients and 150 control subjects matched by gender, age, r...

  5. Pontryagin's principle for control problems in age-dependent population dynamics.

    PubMed

    Brokate, M

    1985-01-01

    In this paper, Pontryagin's principle is proved for a fairly general problem of optimal control of populations with continuous time and age variable. As a consequence, maximum principles are developed for an optimal harvesting problem and a problem of optimal birth control.

  6. Unraveling the Limits of Mitochondrial Control Region to Estimate the Fine Scale Population Genetic Differentiation in Anadromous Fish Tenualosa ilisha.

    PubMed

    Verma, Rashmi; Singh, Mahender; Kumar, Sudhir

    2016-01-01

    The mitochondrial control region has been the first choice for examining the population structure but hypervariability and homoplasy have reduced its suitability. We analysed eight populations using control region for examining the population structure of Hilsa. Although the control region analysis revealed broad structuring between the Arabian Sea and Bay of Bengal (F ST  0.0441, p < 0.001) it was unable to detect structure among riverine populations. These results suggest that the markers used must be able to distinguish populations and control region has led to an underestimation of genetic differentiation among populations of Hilsa. PMID:27313951

  7. Unraveling the Limits of Mitochondrial Control Region to Estimate the Fine Scale Population Genetic Differentiation in Anadromous Fish Tenualosa ilisha

    PubMed Central

    Verma, Rashmi; Singh, Mahender; Kumar, Sudhir

    2016-01-01

    The mitochondrial control region has been the first choice for examining the population structure but hypervariability and homoplasy have reduced its suitability. We analysed eight populations using control region for examining the population structure of Hilsa. Although the control region analysis revealed broad structuring between the Arabian Sea and Bay of Bengal (FST  0.0441, p < 0.001) it was unable to detect structure among riverine populations. These results suggest that the markers used must be able to distinguish populations and control region has led to an underestimation of genetic differentiation among populations of Hilsa. PMID:27313951

  8. The biology of small, introduced populations, with special reference to biological control

    PubMed Central

    Fauvergue, Xavier; Vercken, Elodie; Malausa, Thibaut; Hufbauer, Ruth A

    2012-01-01

    Populations are introduced into novel environments in different contexts, one being the biological control of pests. Despite intense efforts, less than half introduced biological control agents establish. Among the possible approaches to improve biological control, one is to better understand the processes that underpin introductions and contribute to ecological and evolutionary success. In this perspective, we first review the demographic and genetic processes at play in small populations, be they stochastic or deterministic. We discuss the theoretical outcomes of these different processes with respect to individual fitness, population growth rate, and establishment probability. Predicted outcomes differ subtly in some cases, but enough so that the evaluating results of introductions have the potential to reveal which processes play important roles in introduced populations. Second, we attempt to link the theory we have discussed with empirical data from biological control introductions. A main result is that there are few available data, but we nonetheless report on an increasing number of well-designed, theory-driven, experimental approaches. Combining demography and genetics from both theoretical and empirical perspectives highlights novel and exciting avenues for research on the biology of small, introduced populations, and great potential for improving both our understanding and practice of biological control. PMID:22949919

  9. How to control chaotic behaviour and population size with proportional feedback

    NASA Astrophysics Data System (ADS)

    Liz, Eduardo

    2010-01-01

    We study the control of chaos in one-dimensional discrete maps as they often occur in modelling population dynamics. For managing the population, we seek to suppress any possible chaotic behavior, leading the system to a stable equilibrium. In this Letter, we make a rigorous analysis of the proportional feedback method under certain conditions fulfilled by a wide family of maps. We show that it is possible to stabilize the chaotic dynamics towards a globally stable positive equilibrium, that can be chosen among a broad range of possible values. In particular, the size of the population can be enhanced by control in form of population reduction. This paradoxical phenomenon is known as the hydra effect, and it has important implications in the design of strategies in such areas as fishing, pest management, and conservation biology.

  10. Population genetics of Chrysoperla externa (Neuroptera: Chrysopidae) and implications for biological control.

    PubMed

    Lavagnini, T C; Morales, A C; Freitas, S

    2015-11-01

    Green lacewings are insects with great potential to be use in the biological control of agricultural pests, but relatively few studies have attempted to understand the genetic structure of these agents, especially those of predatory insects. The purpose of this study was to characterize genetically populations of C. externa using sequences of subunit I of the cytochrome oxidase, a mitochondrial gene, and examine the population structure of this species in sampled areas in São Paulo state. The results indicate high genetic diversity but no genetic structure, detected by AMOVA analysis, and high levels of haplotype sharing in the network. These genetic patterns could be a consequence of environmental homogeneity provided by agroecosystem (citrus orchard), allowing gene flow among populations. Probably there is a unique population in the area sampled that could be used as a population (genetic) source for mass-reared and posterior release in these farms.

  11. Population ecology of feral horses in an era of fertility control management

    USGS Publications Warehouse

    Ransom, J.I.

    2012-01-01

    Management of wildlife often requires intervention to regulate growth of populations that would otherwise become overabundant. Controlling fecundity using contraceptives has become an increasingly popular tool for attempting to manage locally overabundant wildlife species, but the population-level effects of such applications are largely unknown. Contraceptive treatments can produce unexpected feedbacks that act on births, survival, immigration, and emigration. Such feedbacks may considerably influence our ability to regulate populations using fertility control. I followed feral horses (Equus caballus) in three intensively managed populations to assess longitudinal treatment effects on demography. The transient contraceptive porcine zona pellucida (PZP) produced longer duration of infertility than intended. Repeated PZP vaccinations of females extended the duration of infertility far beyond the targeted management period, with time to first post-treatment parturition increasing 411days for every annual inoculation received. When these animals did conceive and give birth, parturition was later in the year and temporally asynchronous with forage abundance. An average of 30% (range=11–77%) of females were contracepted annually during the treatment period in all three populations and apparent annual population growth rate was 4–9% lower in the post-treatment years as compared to pretreatment years. Population growth was positive, however, and increased steadily every year that a management removal did not occur. The observed number of births was 33% fewer than the expected number of births, based on number of treated females, individual efficacy of treatment, and number of untreated females and their age-specific fecundity rates. Only half of this difference was explained by the apparent residual effect of treatment. Birth rate in the youngest untreated females (age 2–5 years old) was reduced in years when their conspecifics were treated, enhancing the effects of

  12. Evidence-based control of canine rabies: a critical review of population density reduction.

    PubMed

    Morters, Michelle K; Restif, Olivier; Hampson, Katie; Cleaveland, Sarah; Wood, James L N; Conlan, Andrew J K

    2013-01-01

    Control measures for canine rabies include vaccination and reducing population density through culling or sterilization. Despite the evidence that culling fails to control canine rabies, efforts to reduce canine population density continue in many parts of the world. The rationale for reducing population density is that rabies transmission is density-dependent, with disease incidence increasing directly with host density. This may be based, in part, on an incomplete interpretation of historical field data for wildlife, with important implications for disease control in dog populations. Here, we examine historical and more recent field data, in the context of host ecology and epidemic theory, to understand better the role of density in rabies transmission and the reasons why culling fails to control rabies. We conclude that the relationship between host density, disease incidence and other factors is complex and may differ between species. This highlights the difficulties of interpreting field data and the constraints of extrapolations between species, particularly in terms of control policies. We also propose that the complex interactions between dogs and people may render culling of free-roaming dogs ineffective irrespective of the relationship between host density and disease incidence. We conclude that vaccination is the most effective means to control rabies in all species.

  13. Communicable disease control in a migrant seasonal workers population: a case study in Norway.

    PubMed

    Guerin, P J; Vold, L; Aavitsland, P

    2005-03-01

    Reliable data on the health status of migrant seasonal workers in Europe is scarce. Access to public health care for this population depends on national regulations, and their legal status in host countries. In this manuscript we describe a case study of a salmonellosis outbreak that occurred in Norway, and highlight the difficulties encountered in applying control measures in a population of seasonal migrant farm workers. Surveillance and control of infectious diseases need to be supported by legislation which makes implementation of control measures possible. Efforts have been made to improve the rights for migrants in Europe with regard to healthcare, but seasonal migrant workers still remain largely outsiders where these measures are concerned. Special attention should be given to this disadvantaged group in terms of social rights and healthcare. Preparedness plans should be improved to deal with contagious pathogens involving the seasonal migrant population. PMID:15827370

  14. Controlling populations of invasive pygmy mussel (Xenostrobus securis) through citizen science and environmental DNA.

    PubMed

    Miralles, Laura; Dopico, Eduardo; Devlo-Delva, Floriaan; Garcia-Vazquez, Eva

    2016-09-15

    Early detection of dangerous exotic species is crucial for stopping marine invasions. The New Zealand pygmy mussel Xenostrobus securis is a problematic species in coasts of temperate regions in the northern hemisphere. In this study we have controlled a population of this invader that recently expanded in a north Iberian estuary with both a participatory approach involving researchers and citizens, and employing a sensitive eDNA-based tool to monitor the population expansion in the estuary. Results demonstrate successful eradication of pygmy mussels in the outer part of the estuary with citizen science and the practical utility of eDNA for controlling biological invasions. PMID:27381987

  15. Population reduction as a factor in the control of skunk rabies in Alberta.

    PubMed

    Rosatte, R C; Pybus, M J; Gunson, J R

    1986-10-01

    Population reduction is being used currently to combat skunk rabies in Alberta. A total of 2,398 striped skunks (Mephitis mephitis) were removed from three counties of southern Alberta during 1980-1983 in an effort to combat rabies outbreaks in those areas. The methods employed included trapping, poisoning, and shooting. Skunks in Forty Mile County have been rabies-free for 4 yr and the outbreaks in Newell and Warner counties appear to be under control. The data suggest that population reduction has been effective in controlling rabies in those areas.

  16. Controlling populations of invasive pygmy mussel (Xenostrobus securis) through citizen science and environmental DNA.

    PubMed

    Miralles, Laura; Dopico, Eduardo; Devlo-Delva, Floriaan; Garcia-Vazquez, Eva

    2016-09-15

    Early detection of dangerous exotic species is crucial for stopping marine invasions. The New Zealand pygmy mussel Xenostrobus securis is a problematic species in coasts of temperate regions in the northern hemisphere. In this study we have controlled a population of this invader that recently expanded in a north Iberian estuary with both a participatory approach involving researchers and citizens, and employing a sensitive eDNA-based tool to monitor the population expansion in the estuary. Results demonstrate successful eradication of pygmy mussels in the outer part of the estuary with citizen science and the practical utility of eDNA for controlling biological invasions.

  17. Population and forensic genetic analyses of mitochondrial DNA control region variation from six major provinces in the Korean population.

    PubMed

    Hong, Seung Beom; Kim, Ki Cheol; Kim, Wook

    2015-07-01

    We generated complete mitochondrial DNA (mtDNA) control region sequences from 704 unrelated individuals residing in six major provinces in Korea. In addition to our earlier survey of the distribution of mtDNA haplogroup variation, a total of 560 different haplotypes characterized by 271 polymorphic sites were identified, of which 473 haplotypes were unique. The gene diversity and random match probability were 0.9989 and 0.0025, respectively. According to the pairwise comparison of the 704 control region sequences, the mean number of pairwise differences between individuals was 13.47±6.06. Based on the result of mtDNA control region sequences, pairwise FST genetic distances revealed genetic homogeneity of the Korean provinces on a peninsular level, except in samples from Jeju Island. This result indicates there may be a need to formulate a local mtDNA database for Jeju Island, to avoid bias in forensic parameter estimates caused by genetic heterogeneity of the population. Thus, the present data may help not only in personal identification but also in determining maternal lineages to provide an expanded and reliable Korean mtDNA database. These data will be available on the EMPOP database via accession number EMP00661.

  18. Strategic use of communication to market cancer prevention and control to vulnerable populations.

    PubMed

    Kreps, Gary L

    2008-01-01

    There are significant challenges to communicating relevant cancer prevention and control information to health care consumers due both to the complexities of the health information to be communicated and the complexities of health communication, especially with vulnerable populations. The need for effective communication about cancer risks, early detection, prevention, care, and survivorship is particularly acute, yet also tremendously complex, for reaching vulnerable populations, those groups of people who are most likely to suffer significantly higher levels of morbidity and mortality from cancers than other segments of the population. These vulnerable populations, typically the poorest, lowest educated, and most disenfranchised members of modern society, are heir to serious cancer-related health disparities. Vulnerable populations often have health literacy difficulties, cultural barriers, and economic challenges to accessing and making sense of relevant health information. This paper examines these challenges to communicating relevant information to vulnerable populations and suggests strategies for effectively using different communication media for marketing cancer prevention and control to reduce health disparities and promote public health.

  19. Constrained control landscape for population transfer in a two-level system.

    PubMed

    Moore Tibbetts, Katharine; Rabitz, Herschel

    2015-02-01

    The growing success of controlling the dynamics of quantum systems has been ascribed to the favorable topology of the quantum control landscape, which represents the physical observable as a function of the control field. The landscape contains no suboptimal trapping extrema when reasonable physical assumptions are satisfied, including that no significant constraints are placed on the control resources. A topic of prime interest is understanding the effects of control field constraints on the apparent landscape topology, as constraints on control resources are inevitable in the laboratory. This work particularly explores the effects of constraining the control field fluence on the topology and features of the control landscape for pure-state population transfer in a two-level system through numerical simulations, where unit probability population transfer in the system is only accessible in the strong coupling regime within the model explored here. With the fluence and three phase variables used for optimization, no local optima are found on the landscape, although saddle features are widespread at low fluence values. Global landscape optima are found to exist at two disconnected regions of the fluence that possess distinct topologies and structures. Broad scale connected optimal level sets are found when the fluence is sufficiently large, while the connectivity is reduced as the fluence becomes more constrained. These results suggest that seeking optimal fields with constrained fluence or other resources may encounter complex landscape features, calling for sophisticated algorithms that can efficiently find optimal controls. PMID:25515970

  20. The moral lens of population control: condoms and controversies in southern Malawi.

    PubMed

    Kaler, Amy

    2004-06-01

    The study presents an investigation of stories about condoms in southern Malawi. Malawians' concerns about coercive population control imposed by a national government or international cabal provide a moral lens through which condoms and other health promotions are viewed, with unknown but probably negative impact on the use of condoms. The focus of the study is on the long shadow cast by population control because it is underresearched and, in fact, virtually unmentioned in most studies of health promotion, yet appears to be common if not ubiquitous. Moreover, this long shadow poses a distinct challenge to HIV-prevention and intervention efforts. The data for the study were gathered by six Malawian research assistants in Balaka district, in southern Malawi, who kept journals over a period of three years in which they recorded conversations and everyday chats that they observed. These journals demonstrate that condoms do not arrive in communities as neutral, value-free objects; rather they enter a social setting permeated with ideas about health, self-protection, and danger. The lens of population control has proved to be both durable and flexible, providing a moral context in which both commodities and actors can be understood. Disentangling condoms from the symbolic nexus in which they are fused with disease, population control, and malevolence will be an ongoing challenge in the struggle to prevent the spread of HIV/AIDS in Malawi.

  1. Compensatory mechanisms in Great Lakes sea lamprey populations: implications for alternative control strategies

    USGS Publications Warehouse

    Jones, Michael L.; Bergstedt, R.A.; Twohey, Michael B.; Fodale, Michael F.; Cuddy, Douglas W.; Slade, Jeffrey W.

    2003-01-01

    Compensatory mechanisms are demographic processes that tend to increase population growth rates at lower population density. These processes will tend to reduce the effectiveness of actions that use controls on reproductive success to suppress sea lamprey (Petromyzon marinus), an economically important pest in the Great Lakes. Historical evidence for compensatory mechanisms in sea lamprey populations was reviewed, and revealed: (1) strong evidence for shifts in sex ratios as sea lamprey abundance was reduced in the early years of the control program; (2) weak and equivocal evidence for increased growth rates of sea lamprey cohorts re-colonizing streams following a lampricide treatment; and (3) suggestions of other compensatory processes, such as earlier ages at metamorphosis, but with little empirical evidence. Larval size distribution data for cohorts in the first and second years following a lampricide treatment (26 pairs of cohorts in 20 streams) was analyzed and did not indicate a consistent pattern of more rapid growth of the first colonizing cohort (only 11 of 33 cases). To test for compensation between spawning and age-1 in sea lamprey populations, data were analyzed for 49 stream-years for which spawning female abundance was known and age-1 abundance was estimated in the following year. A fit of these data to a Ricker stock-recruitment function showed evidence for compensation, measured as reduced survival to age 1 at higher abundance of spawning females. More obvious, however, was a large amount of density-independent variation in survival, which tends to mask evidence for compensatory survival. The results were applied to a simple model that simulates sea lamprey populations and their control in a hypothetical lake. Control strategies that targeted reproductive success performed far less well than comparable strategies that targeted larval populations, because density-independent recruitment variation leads to occasional strong year classes even when

  2. Current status and future directions of the population control policies in Korea.

    PubMed

    Cho, N H; Seo, M H

    1989-07-01

    Recent changes in demographic and socioeconomic conditions in Korea are reviewed, as are population control policies so that future policy directions can be established. Major data sources include the 1988 National Fertility and Family Health Survey and the 1985 Population and Housing Census of NBOS, EPB. The Korean population increased from 25.0 million in 1960 to 42.4 million in 1989. Population growth rate declined from 3.0% per annum to l.0% at the same time. The total fertility rate went down from 6.0/women to 1.6, from 1960 to 1987. This was due to a family planning program and socioeconomic development. In the Sixth Five-Year Plan (1987-1991), the government changed the demographic goals to further reduce the population growth rate to 0.96% by 1991. The estimated 1987 population of 41.6 million should reach 43.2 million by 1991. Korea will face 3 major population problems: an increase of the elderly population, rapid urbanization and shortage of resources. Emigration programs have been carried out to relieve the pressure of population. For the last 29 years, rural to urban migration has existed. A national family planning program exists. 16.4 million acceptors have received contraception under this program. There are, however, a number of problems. Reduction in population growth will help the world food supply problem and the housing shortage. Energy use has grown. Population and environmental planning should work together. Goals should change from reduction of fertility to eliminating problems with contraceptive acceptance and use effectiveness. There should be a greater choice of methods of contraception. The government functions of the family planning program should be given over to private organizations. The family planning program should be integrated with public health programs. Acceptors should pay for their contraceptives. The family planning program should enlarge its realm of activities. The information, education, communication part of the program

  3. Control of mushroom sciarid fly Lycoriella ingenua populations with insect growth regulators applied by soil drench.

    PubMed

    Erler, F; Polat, E; Demir, H; Catal, M; Tuna, G

    2011-06-01

    Mushroom sciarid fly Lycoriella ingenua (Dufour, 1839) comb. nov., is one of the most common fly pests affecting the cultivation of Agaricus bisporus (Lange) Imbach in Turkey. In this study, eight insect growth regulators (IGRs)--diflubenzuron, flufenoxuron, lufenuron, methoprene, novaluron, pyriproxyfen, teflubenzuron, and triflumuron-were tested for their potential to control L. ingenua populations in two successive growing periods. Treatments were targeted at larvae as soil drenches; treatment efficacy was evaluated by assessing adult emergence and larval damage. These products were compared with a control treated with water (negative control) and a conventional chemical insecticide (chlorpyrifos ethyl) (positive control). Treatments with the IGRs caused significant reductions in emerging adult numbers and sporophore damage rates compared with the water-treated control over the two growing periods. Of the IGRs tested, novaluron, diflubenzuron, and teflubenzuron had significantly lower numbers of emerging adults than the rest of the IGRs and chlorpyrifos ethyl-treated control in both periods. Treatments with teflubenzuron, pyriproxyfen, novaluron, and diflubenzuron resulted in significantly lower sporophore damage rates than all other treatments. Compared with negative control, there were no significant yield reductions due to applications of selected IGRs. The results suggest that all the IGRs tested can be used as alternatives to conventional pesticides in controlling L. ingenua populations on mushroom. PMID:21735902

  4. Organization of population-based cancer control programs: Europe and the world.

    PubMed

    Otter, Renée; Qiao, You-Lin; Burton, Robert; Samiei, Massoud; Parkin, Max; Trapido, Edward; Weller, David; Magrath, Ian; Sutcliffe, Simon

    2009-01-01

    As cancer is to a large extent avoidable and treatable, a cancer control program should be able to reduce mortality and morbidity and improve the quality of life of cancer patients and their families. However, the extent to which the goals of a cancer control program can be achieved will depend on the resource constraints a country faces. Such population-based cancer control plans should prioritize effective interventions and programs that are beneficial to the largest part of the population, and should include activities devoted to prevention, screening and early detection, treatment, palliation and end-of-life care, and rehabilitation. In order to develop a successful cancer control program, leadership and the relevant stakeholders, including patient organizations, need to be identified early on in the process so that all partners can take ownership and responsibility for the program. Various tools have been developed to aid them in the planning and implementation process. However, countries developing a national cancer control program would benefit from a discussion of different models for planning and delivery of population-based cancer control in settings with differing levels of resource commitment, in order to determine how best to proceed given their current level of commitment, political engagement and resources. As the priority assigned to different components of cancer control will differ depending on available resources and the burden and pattern of cancer, it is important to consider the relative roles of prevention, early detection, diagnosis, treatment, rehabilitation and palliative care in a cancer control program, as well as how to align available resources to meet prioritized needs. Experiences from countries with differing levels of resources are presented and serve to illustrate the difficulties in developing and implementing cancer control programs, as well as the innovative strategies that are being used to maximize available resources and

  5. Opioid system genes in alcoholism: a case-control study in Croatian population.

    PubMed

    Cupic, B; Stefulj, J; Zapletal, E; Matosic, A; Bordukalo-Niksic, T; Cicin-Sain, L; Gabrilovac, J

    2013-10-01

    Due to their involvement in dependence pathways, opioid system genes represent strong candidates for association studies investigating alcoholism. In this study, single nucleotide polymorphisms within the genes for mu (OPRM1) and kappa (OPRK1) opioid receptors and precursors of their ligands - proopiomelanocortin (POMC), coding for beta-endorphin and prodynorphin (PDYN) coding for dynorphins, were analyzed in a case-control study that included 354 male alcohol-dependent and 357 male control subjects from Croatian population. Analysis of allele and genotype frequencies of the selected polymorphisms of the genes OPRM1/POMC and OPRK1/PDYN revealed no differences between the tested groups. The same was true when alcohol-dependent persons were subdivided according to the Cloninger's criteria into type-1 and type-2 groups, known to differ in the extent of genetic control. Thus, the data obtained suggest no association of the selected polymorphisms of the genes OPRM1/POMC and OPRK1/PDYN with alcoholism in Croatian population.

  6. Dynamic balance of multiple myeloma clonogenic side population cell percentages controlled by environmental conditions

    PubMed Central

    Wen, Jianguo; Tao, Wenjing; Kuiatse, Isere; Lin, Pei; Feng, Yongdong; Jones, Richard J.; Orlowski, Robert Z.; Zu, Youli

    2014-01-01

    Cancer stem cells (CSCs) are key drivers of tumor progression and disease recurrence in multiple myeloma (MM). However, little is known about the regulation of MM stem cells. Here, we show that a population of MM cells, known as the side population (SP), exhibits stem-like properties. Cells that constitute the SP in primary MM isolates are negative or seldom expressed for CD138 and CD20 markers. Moreover, the SP population contains stem cells that belong to the same lineage as the mature neoplastic plasma cells (MPC). Importantly, our data indicate that the side (SP) and non-side (NSP) population percentages in heterogeneous MM cells are balanced, and that this balance can be achieved through a prolonged in vitro culture. Furthermore, we show that SP cells, with confirmed molecular characteristics of MM stem cells, can be regenerated from purified NSP cell populations. We also show that the percentage of SP cells can be enhanced by the hypoxic stress, which is frequently observed within MM tumors. Finally, hypoxic stress enhanced the expression of transforming growth factor β1 (TGF-β1) and blocking the TGF-β1 signaling pathway inhibited the NSP de-differentiation. Taken together, these findings indicate that the balance between MM SP and NSP is regulated by environmental factors and TGF-β1 pathway is involved in hypoxia-induced increase of SP population. Understanding the mechanisms that facilitate SP maintenance will accelerate the design of novel therapeutics aimed at controlling these cells in MM. PMID:25042852

  7. Interplay of population genetics and dynamics in the genetic control of mosquitoes

    PubMed Central

    Alphey, Nina; Bonsall, Michael B.

    2014-01-01

    Some proposed genetics-based vector control methods aim to suppress or eliminate a mosquito population in a similar manner to the sterile insect technique. One approach under development in Anopheles mosquitoes uses homing endonuclease genes (HEGs)—selfish genetic elements (inherited at greater than Mendelian rate) that can spread rapidly through a population even if they reduce fitness. HEGs have potential to drive introduced traits through a population without large-scale sustained releases. The population genetics of HEG-based systems has been established using discrete-time mathematical models. However, several ecologically important aspects remain unexplored. We formulate a new continuous-time (overlapping generations) combined population dynamic and genetic model and apply it to a HEG that targets and knocks out a gene that is important for survival. We explore the effects of density dependence ranging from undercompensating to overcompensating larval competition, occurring before or after HEG fitness effects, and consider differences in competitive effect between genotypes (wild-type, heterozygotes and HEG homozygotes). We show that population outcomes—elimination, suppression or loss of the HEG—depend crucially on the interaction between these ecological aspects and genetics, and explain how the HEG fitness properties, the homing rate (drive) and the insect's life-history parameters influence those outcomes. PMID:24522781

  8. Yanomamo ecology, population control, and their relationship to slash and burn agriculture.

    PubMed

    Owl, M Y

    1976-01-01

    Population control among the Yanomamo tribe of the Amazonian tropical rainforest is studied. 25% of male deaths are due to warfare. A male-female balance is achieved by the practice of infantcide, especially among female infants. The male:female ratio among the under-15 age group is 135:100, belying the tribe's contention that neither sex is more likely to be killed than the other. The major population controlffactor, however, is disease with about 54.2% of adult deaths due to malaria, and other communicable disease accounting for 11.7%. Other population controls are abortion and postnatal sex taboos, although the latter is for the most part overruled by the practice of infanticide for any child born while a previous child is still nursing. The intense intervillage warfare is increased by the shortage of women, resulting from female infanticide combined with polygamy and marriage alliances in which even unborn females are promised. Because there is war, male children are preferred and the cycle continues. Other observers, however, feel that the constant warfare is part of the need for new garden sites brought about by reliance on slash and burn agriculture. The author believes the shortage of women is just a side effect of population control occasioned by a protein shortage. PMID:12334855

  9. Suicide by people in a community justice pathway: population-based nested case-control study.

    PubMed

    King, Carlene; Senior, Jane; Webb, Roger T; Millar, Tim; Piper, Mary; Pearsall, Alison; Humber, Naomi; Appleby, Louis; Shaw, Jenny

    2015-08-01

    The elevated risk of suicide in prison and after release is a well-recognised and serious problem. Despite this, evidence concerning community-based offenders' suicide risk is sparse. We conducted a population-based nested case-control study of all people in a community justice pathway in England and Wales. Our data show 13% of general population suicides were in community justice pathways before death. Suicide risks were highest among individuals receiving police cautions, and those having recent, or impending prosecution for sexual offences. Findings have implications for the training and practice of clinicians identifying and assessing suicidality, and offering support to those at elevated risk.

  10. Controlling range expansion in habitat networks by adaptively targeting source populations.

    PubMed

    Hock, Karlo; Wolff, Nicholas H; Beeden, Roger; Hoey, Jessica; Condie, Scott A; Anthony, Kenneth R N; Possingham, Hugh P; Mumby, Peter J

    2016-08-01

    Controlling the spread of invasive species, pests, and pathogens is often logistically limited to interventions that target specific locations at specific periods. However, in complex, highly connected systems, such as marine environments connected by ocean currents, populations spread dynamically in both space and time via transient connectivity links. This results in nondeterministic future distributions of species in which local populations emerge dynamically and concurrently over a large area. The challenge, therefore, is to choose intervention locations that will maximize the effectiveness of the control efforts. We propose a novel method to manage dynamic species invasions and outbreaks that identifies the intervention locations most likely to curtail population expansion by selectively targeting local populations most likely to expand their future range. Critically, at any point during the development of the invasion or outbreak, the method identifies the local intervention that maximizes the long-term benefit across the ecosystem by restricting species' potential to spread. In so doing, the method adaptively selects the intervention targets under dynamically changing circumstances. To illustrate the effectiveness of the method we applied it to controlling the spread of crown-of-thorns starfish (Acanthaster sp.) outbreaks across Australia's Great Barrier Reef. Application of our method resulted in an 18-fold relative improvement in management outcomes compared with a random targeting of reefs in putative starfish control scenarios. Although we focused on applying the method to reducing the spread of an unwanted species, it can also be used to facilitate the spread of desirable species through connectivity networks. For example, the method could be used to select those fragments of habitat most likely to rebuild a population if they were sufficiently well protected. PMID:26633077

  11. Utilizing population controls in rare-variant case-parent association tests.

    PubMed

    Jiang, Yu; Satten, Glen A; Han, Yujun; Epstein, Michael P; Heinzen, Erin L; Goldstein, David B; Allen, Andrew S

    2014-06-01

    There is great interest in detecting associations between human traits and rare genetic variation. To address the low power implicit in single-locus tests of rare genetic variants, many rare-variant association approaches attempt to accumulate information across a gene, often by taking linear combinations of single-locus contributions to a statistic. Using the right linear combination is key-an optimal test will up-weight true causal variants, down-weight neutral variants, and correctly assign the direction of effect for causal variants. Here, we propose a procedure that exploits data from population controls to estimate the linear combination to be used in an case-parent trio rare-variant association test. Specifically, we estimate the linear combination by comparing population control allele frequencies with allele frequencies in the parents of affected offspring. These estimates are then used to construct a rare-variant transmission disequilibrium test (rvTDT) in the case-parent data. Because the rvTDT is conditional on the parents' data, using parental data in estimating the linear combination does not affect the validity or asymptotic distribution of the rvTDT. By using simulation, we show that our new population-control-based rvTDT can dramatically improve power over rvTDTs that do not use population control information across a wide variety of genetic architectures. It also remains valid under population stratification. We apply the approach to a cohort of epileptic encephalopathy (EE) trios and find that dominant (or additive) inherited rare variants are unlikely to play a substantial role within EE genes previously identified through de novo mutation studies.

  12. Controlling range expansion in habitat networks by adaptively targeting source populations.

    PubMed

    Hock, Karlo; Wolff, Nicholas H; Beeden, Roger; Hoey, Jessica; Condie, Scott A; Anthony, Kenneth R N; Possingham, Hugh P; Mumby, Peter J

    2016-08-01

    Controlling the spread of invasive species, pests, and pathogens is often logistically limited to interventions that target specific locations at specific periods. However, in complex, highly connected systems, such as marine environments connected by ocean currents, populations spread dynamically in both space and time via transient connectivity links. This results in nondeterministic future distributions of species in which local populations emerge dynamically and concurrently over a large area. The challenge, therefore, is to choose intervention locations that will maximize the effectiveness of the control efforts. We propose a novel method to manage dynamic species invasions and outbreaks that identifies the intervention locations most likely to curtail population expansion by selectively targeting local populations most likely to expand their future range. Critically, at any point during the development of the invasion or outbreak, the method identifies the local intervention that maximizes the long-term benefit across the ecosystem by restricting species' potential to spread. In so doing, the method adaptively selects the intervention targets under dynamically changing circumstances. To illustrate the effectiveness of the method we applied it to controlling the spread of crown-of-thorns starfish (Acanthaster sp.) outbreaks across Australia's Great Barrier Reef. Application of our method resulted in an 18-fold relative improvement in management outcomes compared with a random targeting of reefs in putative starfish control scenarios. Although we focused on applying the method to reducing the spread of an unwanted species, it can also be used to facilitate the spread of desirable species through connectivity networks. For example, the method could be used to select those fragments of habitat most likely to rebuild a population if they were sufficiently well protected.

  13. Controlling for non-independence in comparative analysis of patterns across populations within species

    PubMed Central

    Stone, Graham N.; Nee, Sean; Felsenstein, Joseph

    2011-01-01

    How do we quantify patterns (such as responses to local selection) sampled across multiple populations within a single species? Key to this question is the extent to which populations within species represent statistically independent data points in our analysis. Comparative analyses across species and higher taxa have long recognized the need to control for the non-independence of species data that arises through patterns of shared common ancestry among them (phylogenetic non-independence), as have quantitative genetic studies of individuals linked by a pedigree. Analyses across populations lacking pedigree information fall in the middle, and not only have to deal with shared common ancestry, but also the impact of exchange of migrants between populations (gene flow). As a result, phenotypes measured in one population are influenced by processes acting on others, and may not be a good guide to either the strength or direction of local selection. Although many studies examine patterns across populations within species, few consider such non-independence. Here, we discuss the sources of non-independence in comparative analysis, and show why the phylogeny-based approaches widely used in cross-species analyses are unlikely to be useful in analyses across populations within species. We outline the approaches (intraspecific contrasts, generalized least squares, generalized linear mixed models and autoregression) that have been used in this context, and explain their specific assumptions. We highlight the power of ‘mixed models’ in many contexts where problems of non-independence arise, and show that these allow incorporation of both shared common ancestry and gene flow. We suggest what can be done when ideal solutions are inaccessible, highlight the need for incorporation of a wider range of population models in intraspecific comparative methods and call for simulation studies of the error rates associated with alternative approaches. PMID:21444315

  14. Population control of the malaria vector Anopheles pseudopunctipennis by habitat manipulation.

    PubMed Central

    Bond, J. Guillermo; Rojas, Julio C.; Arredondo-Jiménez, Juan I.; Quiroz-Martínez, Humberto; Valle, Javier; Williams, Trevor

    2004-01-01

    Insect vector-borne diseases continue to present a major challenge to human health. Understanding the factors that regulate the size of mosquito populations is considered fundamental to the ability to predict disease transmission rates and for vector population control. The mosquito, Anopheles pseudopunctipennis, a vector of Plasmodium spp., breeds in riverside pools containing filamentous algae in Mesoamerica. Breeding pools along 3 km sections of the River Coatan, Chiapas, Mexico were subjected to algal extraction or left as controls in a cross-over trial extending over 2 years. Initial densities of An. pseudopunctipennis larvae were directly proportional to the prevalence of filamentous algae in each breeding site. The extraction of algae brought about a striking decline in the density of An. pseudopunctipennis larvae sustained for about six weeks, and a concurrent reduction in the adult population in both years of the study. Mark-release experiments indicated that dispersal from adjacent untreated areas was unlikely to exert an important influence on the magnitude of mosquito control that we observed. Habitat manipulation by extraction of filamentous algae offers a unique opportunity for sustainable control of this malaria vector. This technique may represent a valuable intervention, complimenting insecticide spraying of households, to minimize Plasmodium transmission rates in Mesoamerica. PMID:15475337

  15. A population-based case-control study of isolated anophthalmia and microphthalmia.

    PubMed

    Vogt, Gábor; Puhó, Erzsébet; Czeizel, Andrew E

    2005-01-01

    The purpose of the study was to reveal the etiological factors in the origin of isolated an/microphthalmia. The dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-2002 containing 56 cases with isolated an/microphthalmia and 22,744 malformed controls with other non-ocular defects from the Hungarian Congenital Abnormality Registry, in addition of 56 matched control pairs and 37,837 population controls without defects from the National Birth Registry, was evaluated. Exposure data and family history were collected (i) prospectively by prenatal logbook and other medical records, (ii) retrospectively through a structured questionnaire filled-in by mothers, and (iii) information obtained by regional nurses at home visit of non-respondent mothers. The autosomal recessive origin of isolated an/microphthalmia was indicated in about 10% of cases on the basis of sib recurrence. Cases with isolated an/microphthalmia had a much shorter mean gestational age and smaller mean birth weight, a much larger proportion of preterm birth and low birthweight. Their mothers were younger with a predominance of first birth order, frequently unmarried with low socioeconomic status. These findings are in agreement with a much higher prevalence at birth of cases with isolated an/microphthalmia in the gypsy population probably due to the interaction of inbreeding effect and low socioeconomic status. Further molecular genetic studies are needed to identify gene mutations of isolated an/microphthalmia in the Hungarian gypsy population.

  16. Discovering modes of an image population through mixture modeling.

    PubMed

    Sabuncu, Mert R; Balci, Serdar K; Golland, Polina

    2008-01-01

    We present iCluster, a fast and efficient algorithm that clusters a set of images while co-registering them using a parameterized, nonlinear transformation model. The output is a small number of template images that represent different modes in a population. This is in contrast with traditional approaches that assume a single template to construct atlases. We validate and explore the algorithm in two experiments. First, we employ iCluster to partition a data set of 416 whole brain MR volumes of subjects aged 18-96 years into three sub-groups, which mainly correspond to age groups. The templates reveal significant structural differences across these age groups that confirm previous findings in aging research. In the second experiment, we run iCluster on a group of 30 patients with dementia and 30 age-matched healthy controls. The algorithm produced three modes that mainly corresponded to a sub-population of healthy controls, a sub-population of patients with dementia and a mixture group that contained both types. These results suggest that the algorithm can be used to discover sub-populations that correspond to interesting structural or functional "modes".

  17. Risk Factors for and Barriers to Control Type-2 Diabetes among Saudi Population

    PubMed Central

    Alneami, Yahya Mari; Coleman, Christopher L.

    2016-01-01

    Background: The prevalence of Type-2 Diabetes is dramatically increasing in urban areas within Saudi Arabia. Hence, Type-2 Diabetes has now become the most common public health problem. Understanding the major risk factors for and barriers to control Type-2 Diabetes may lead to strategies to prevent, control, and reduce in the burden of disease cases. Objective: To describe risk factors for and barriers to control Type- 2 Diabetes in Saudi Arabia. Methods: The literature search was conducted on risk factors for and barriers to control Type- 2 Diabetes in Saudi Arabia using the databases PubMed, MEDLINE, and Google Scholar (2007-2015). The literature search yielded 80 articles, of which 70 articles were included in this review after excluding non-relevant articles. Results: The literature review revealed that obesity, physical inactivity, unhealthy diet, smoking, and aging are the major risk factors for Type-2 Diabetes in Saudi Arabia. Further, the review allocated a complex set of barriers including, lack of education, social support, and healthy environment. These barriers may hinder Saudis with Type-2 Diabetes from controlling their disease. Conclusion: The prevalence of Type-2 Diabetes is high among the Saudi population and represents a major public health problem. Effective research programs are needed to address the modifiable risk factors for and barriers to control Type-2 Diabetes among Saudi population. PMID:27157156

  18. The ethics of population control in rural China, 1979-92.

    PubMed

    Thomas, N

    1995-09-01

    This article identifies some issues of importance in understanding China's policy of population control. This article presents evidence of trends in fertility, population policy, family planning, and socioeconomic change; and then discusses the conflict between fertility preferences and policy that is evident from studies of ideal family size and sex ratios. Some issues that are identified as "uncertain" include the extent of spread of family planning service delivery and its associated insurance schemes, local family planning policies and cadre responsibility systems, the demand for children, the demand for female children, the economic and environmental consequences of population growth, the fairness of reproductive restrictions and their application, and the extent of coercion in the later-longer-fewer policy era. It is argued that an ethical framework for analyzing China's population policy should include answers to questions about the harm to welfare from population growth, the government's right to demand voluntary reproductive sacrifice or to impose demographic or reproductive restrictions and punishment, and the government's right to impose coercion. If it is accepted that population growth in China has adverse consequences and its control would be beneficial to all, then it must be determined what the nature of the relationship should be between the state and the individual. The author refers to Walzer's (1983) position that the legitimacy of Chinese state power depends in part on whether political leaders at all levels are competent and not corrupt. The rights and duties of the government and individuals must be understood not just in terms of political legitimacy but also in terms of social justice. Social justice is dependent upon the degree of horizontal and vertical consultation and accountability, utilitarian consequences, and protected spheres of individual judgement. Utilitarian theories justify the one-child policy, while deontological theories

  19. The control of population growth is the function of the central government.

    PubMed

    1994-04-01

    This speech of Mr. Jiang Zemin, General Secretary of the Central Committee of the Chinese Communist Party and Chairman of the People's Republic of China, before the National Forum on Family Planning Work refers to the need to strictly and effectively implement the family planning program in 1994. Socioeconomic reforms will be occurring simultaneously. Success of the family planning program is attributed to Party Committees, governments, cadres, and the masses. Even though there have been advances made in slowing population growth, the vast size of the Chinese population still poses problems. China's state policy is to modernize and to maintain strict control of overrapid population growth. The strategy is to move toward a market economy, while continuing to slow population growth but without market regulation of population growth. Family planning serves the state and the people through voluntary action. The public must receive "meticulous" education and help with day to day problems in production, daily life, and human reproduction. Government departments and nongovernmental organizations need to work together. Family planning use is the obligation of every citizen, who should be made aware of relevant national policy and of the need for devotion to country. Benefits will be received by the state and families, when family planning is used. Family planning will be cultivated as an honorable act, and boys and girls will be valued equally. The educational program will train leaders and cadres to take a leadership role in practicing family planning. Party organizations and governments at all levels should take personal responsibility for program implementation. Erratic efforts are not good enough; the task is long and arduous. Serious difficulties still exist in rural areas, and program focus should be directed to rural areas and the floating population. Reports were also made at the Forum on the population status and preparatory meetings of the forthcoming women

  20. Phylogeography and population structure of the red stingray, Dasyatis akajei inferred by mitochondrial control region.

    PubMed

    Li, Ning; Chen, Xiao; Sun, Dianrong; Song, Na; Lin, Qin; Gao, Tianxiang

    2015-08-01

    The red stingray Dasyatis akajei is distributed in both marine and freshwater, but little is known about its phylogeography and population structure. We sampled 107 individuals from one freshwater region and 6 coastal localities within the distribution range of D. akajei. Analyses of the first hypervariable region of mitochondrial DNA control region of 474 bp revealed only 17 polymorphism sites that defined 28 haplotypes, with no unique haplotype for the freshwater population. A high level of haplotype diversity and low nucleotide diversity were observed in both marine (h = 0.9393 ± 0.0104, π = 0.0069 ± 0.0040) and freshwater populations (h = 0.8333 ± 0.2224, π = 0.0084 ± 0.0063). Significant level of genetic structure was detected between four marine populations (TZ, WZ, ND and ZZ) via both hierarchical molecular variance analysis (AMOVA) and pairwise FST (with two exceptions), which is unusual for elasmobranchs detected previously over such short geographical distance. However, limited sampling suggested that the freshwater population was not particularly distinct (p > 0.05), but additional samples would be needed to confirm it. Demersal and slow-moving characters likely have contributed to the genetically heterogeneous population structure. The demographic history of D. akajei examined by mismatch distribution analyses, neutrality tests and Bayesian skyline analyses suggested a sudden population expansion dating to upper Pleistocene. The information on genetic diversity and genetic structure will have implications for the management of fisheries and conservation efforts. PMID:24409898

  1. Reconstructing the History of Mesoamerican Populations through the Study of the Mitochondrial DNA Control Region

    PubMed Central

    Gorostiza, Amaya; Acunha-Alonzo, Víctor; Regalado-Liu, Lucía; Tirado, Sergio; Granados, Julio; Sámano, David; Rangel-Villalobos, Héctor; González-Martín, Antonio

    2012-01-01

    The study of genetic information can reveal a reconstruction of human population’s history. We sequenced the entire mtDNA control region (positions 16.024 to 576 following Cambridge Reference Sequence, CRS) of 605 individuals from seven Mesoamerican indigenous groups and one Aridoamerican from the Greater Southwest previously defined, all of them in present Mexico. Samples were collected directly from the indigenous populations, the application of an individual survey made it possible to remove related or with other origins samples. Diversity indices and demographic estimates were calculated. Also AMOVAs were calculated according to different criteria. An MDS plot, based on FST distances, was also built. We carried out the construction of individual networks for the four Amerindian haplogroups detected. Finally, barrier software was applied to detect genetic boundaries among populations. The results suggest: a common origin of the indigenous groups; a small degree of European admixture; and inter-ethnic gene flow. The process of Mesoamerica’s human settlement took place quickly influenced by the region’s orography, which development of genetic and cultural differences facilitated. We find the existence of genetic structure is related to the region’s geography, rather than to cultural parameters, such as language. The human population gradually became fragmented, though they remained relatively isolated, and differentiated due to small population sizes and different survival strategies. Genetic differences were detected between Aridoamerica and Mesoamerica, which can be subdivided into “East”, “Center”, “West” and “Southeast”. The fragmentation process occurred mainly during the Mesoamerican Pre-Classic period, with the Otomí being one of the oldest groups. With an increased number of populations studied adding previously published data, there is no change in the conclusions, although significant genetic heterogeneity can be detected in Pima

  2. Mitochondrial DNA control region diversity in a population from Espirito Santo state, Brazil.

    PubMed

    Sanches, Naiara M; Paneto, Greiciane G; Figueiredo, Raquel F; de Mello, Aline O; Cicarelli, Regina M B

    2014-10-01

    Mitochondrial DNA (mtDNA) analysis has proved to be useful for forensic identification, especially in cases which nuclear DNA markers fail, as in degraded samples or in cases where the biological material has few traces or no nuclear DNA. Moreover, it can be applied in population genetics, inferring the origin of a population. In this work, the entire mtDNA control region of 97 individuals from the state of Espirito Santo, Brazil, was analyzed. We have found 94 different haplotypes yielding a high haplotype diversity of 0.9994 ± 0.0016. The probability of a random match calculated was 1.09. Haplogroup distribution analysis confirmed a highly admixed Latin American population: African lineages (43.3 %), European lineages (32.0 %), Native American lineages (23.7 %) and Asian lineages (1.0 %). We have concluded that this type of tool can be used both in forensic genetics to the study of different human populations, such as highly admixed populations, and in the study of migration's history and colonization of different states and countries of the world.

  3. Does polyandry control population sex ratio via regulation of a selfish gene?

    PubMed Central

    Price, Tom A. R.; Bretman, Amanda; Gradilla, Ana C.; Reger, Julia; Taylor, Michelle L.; Giraldo-Perez, Paulina; Campbell, Amy; Hurst, Gregory D. D.; Wedell, Nina

    2014-01-01

    The extent of female multiple mating (polyandry) can strongly impact on the intensity of sexual selection, sexual conflict, and the evolution of cooperation and sociality. More subtly, polyandry may protect populations against intragenomic conflicts that result from the invasion of deleterious selfish genetic elements (SGEs). SGEs commonly impair sperm production, and so are likely to be unsuccessful in sperm competition, potentially reducing their transmission in polyandrous populations. Here, we test this prediction in nature. We demonstrate a heritable latitudinal cline in the degree of polyandry in the fruitfly Drosophila pseudoobscura across the USA, with northern population females remating more frequently in both the field and the laboratory. High remating was associated with low frequency of a sex-ratio-distorting meiotic driver in natural populations. In the laboratory, polyandry directly controls the frequency of the driver by undermining its transmission. Hence we suggest that the cline in polyandry represents an important contributor to the cline in sex ratio in nature. Furthermore, as the meiotic driver causes sex ratio bias, variation in polyandry may ultimately determine population sex ratio across the USA, a dramatic impact of female mating decisions. As SGEs are ubiquitous it is likely that the reduction of intragenomic conflict by polyandry is widespread. PMID:24695427

  4. Improving blood pressure control in a large multiethnic California population through changes in health care delivery, 2004-2012.

    PubMed

    Shaw, Kate M; Handler, Joel; Wall, Hilary K; Kanter, Michael H

    2014-10-30

    The Kaiser Permanente Southern California (Kaiser) health care system succeeded in improving hypertension control in a multiethnic population by adopting a series of changes in health care delivery. Data from the Healthcare Effectiveness Data and Information Set (HEDIS) was used to assess blood pressure control from 2004 through 2012. Hypertension control increased overall from 54% to 86% during that period, and 80% or more in every subgroup, regardless of race/ethnicity, preferred language, or type of health insurance plan. Health care delivery changes improved hypertension control across a large multiethnic population, which indicates that health care systems can achieve a clinical target goal of 70% for hypertension control in their populations.

  5. [Principle for strategic decision based on population health risk in emergence environmental cadmium pollution control].

    PubMed

    Shang, Qi

    2012-05-01

    The principles for strategic decision in emergence environmental pollution control was summarized based on population health risk and features of emergence events of environmental cadmium pollution. Main task and strategies for the events control was suggested in emergency treatment and post-event for water and soil cadmium pollution respectively. The work, monitoring method, key problems for both environment cadmium pollution and human health risk, and main content of health education for cadmium exposure people was proposed in follow-up action, at meanwhile, achievements of study on human health effects caused by environmental cadmium pollution was introduced briefly over recent years.

  6. Persistence of bromadiolone anticoagulant rodenticide in Arvicola terrestris populations after field control.

    PubMed

    Giraudoux, Patrick; Tremollières, Catherine; Barbier, Brigitte; Defaut, Régis; Rieffel, Dominique; Bernard, Nadine; Lucot, Eric; Berny, Philippe

    2006-11-01

    This paper documents the exposure pattern of a population of small mammals to bromadiolone over time in a field-scale follow up. This is the first assessment of the field-scale effect of such control operation on the availability of bromadiolone-exposed A. terrestris prey to nontarget predator species. It indicates that an important risk of poisoning of nontarget species does exist during large-scale field control operations with bromadiolone, which is contradictory to results obtained from laboratory experiments in the early 1980s and consistent with the secondary poisoning hazards due to repeated exposure regularly reported during the past 20 years. PMID:16616915

  7. Strategies to control a common carp population by pulsed commercial harvest

    USGS Publications Warehouse

    Colvin, Michael E.; Pierce, Clay; Stewart, Timothy W.; Grummer, Scott E.

    2012-01-01

    Commercial fisheries are commonly used to manage nuisance fishes in freshwater systems, but such efforts are often unsuccessful. Strategies for successfully controlling a nuisance population of common carp Cyprinus carpio by pulsed commercial harvest were evaluated with a combination of (1) field sampling, (2) population estimation and CPUE indexing, and (3) simulation using an exponential semidiscrete biomass dynamics model (SDBDM). The range of annual fishing mortalities (F) that resulted in successful control (F = 0.244–0.265) was narrow. Common carp biomass dynamics were sensitive to unintentional underharvest due to high rates of surplus production and a biomass doubling time of 2.7 years. Simulations indicated that biomanipulation never achieved successful control unless supplemental fishing mortality was imposed. Harvest of a majority of annual production was required to achieve successful control, as indicated by the ecotrophic coefficient (EC). Readily available biomass data and tools such as SDBDMs and ECs can be used in an adaptive management framework to successfully control common carp and other nuisance fishes by pulsed commercial fishing.

  8. Perceptions of the causes of bladder cancer, nasal cancer, and mesothelioma among cases and population controls.

    PubMed

    Teschke, K; van Zwieten, L

    1999-12-01

    To understand the reasons for underreporting of occupational cancers, we investigated cases' perceptions of the causes of cancer. As part of a case-control study in the province of British Columbia, Canada, 105 bladder cancer cases, 48 nasal cancer cases, 51 mesothelioma cases, and 159 population-based controls (frequency matched to cases on age and sex) were interviewed using structured questions about their smoking, medical, residential, occupational, and carcinogen exposure histories. We asked cases what they thought caused their disease, and asked population controls about their understanding of the etiologies of the three cancers. Most cases and controls (69%) indicated that they had "no idea" about causes, with the exception that the majority of mesothelioma cases (70%) recognized asbestos as a cause. Smoking was perceived as a cause of bladder cancer by 21 percent of cases. Many cases knew about the asbestos and smoking etiologies from discussions with their physicians. Chemicals were commonly cited as causes of nasal and bladder cancer, but very few specific known or probable carcinogens for these sites were named. Cases (12%) more frequently than controls (2%) thought prior disease or trauma was a cause for all three types of cancer. Other etiologic factors less frequently listed by subjects included environmental pollution, hereditary factors, drugs, and radiation. Most cases recognized the major cause of mesothelioma, but few subjects knew about lifestyle or occupational causes of bladder cancer or nasal cancer, suggesting that education about the multiple cancer risks of smoking and about occupational carcinogens needs to be improved.

  9. Closed-loop control of epileptiform activities in a neural population model using a proportional-derivative controller

    NASA Astrophysics Data System (ADS)

    Wang, Jun-Song; Wang, Mei-Li; Li, Xiao-Li; Ernst, Niebur

    2015-03-01

    Epilepsy is believed to be caused by a lack of balance between excitation and inhibitation in the brain. A promising strategy for the control of the disease is closed-loop brain stimulation. How to determine the stimulation control parameters for effective and safe treatment protocols remains, however, an unsolved question. To constrain the complex dynamics of the biological brain, we use a neural population model (NPM). We propose that a proportional-derivative (PD) type closed-loop control can successfully suppress epileptiform activities. First, we determine the stability of root loci, which reveals that the dynamical mechanism underlying epilepsy in the NPM is the loss of homeostatic control caused by the lack of balance between excitation and inhibition. Then, we design a PD type closed-loop controller to stabilize the unstable NPM such that the homeostatic equilibriums are maintained; we show that epileptiform activities are successfully suppressed. A graphical approach is employed to determine the stabilizing region of the PD controller in the parameter space, providing a theoretical guideline for the selection of the PD control parameters. Furthermore, we establish the relationship between the control parameters and the model parameters in the form of stabilizing regions to help understand the mechanism of suppressing epileptiform activities in the NPM. Simulations show that the PD-type closed-loop control strategy can effectively suppress epileptiform activities in the NPM. Project supported by the National Natural Science Foundation of China (Grant Nos. 61473208, 61025019, and 91132722), ONR MURI N000141010278, and NIH grant R01EY016281.

  10. Population Dynamics of Owned, Free-Roaming Dogs: Implications for Rabies Control

    PubMed Central

    Conan, Anne; Akerele, Oluyemisi; Simpson, Greg; Reininghaus, Bjorn; van Rooyen, Jacques; Knobel, Darryn

    2015-01-01

    Background Rabies is a serious yet neglected public health threat in resource-limited communities in Africa, where the virus is maintained in populations of owned, free-roaming domestic dogs. Rabies elimination can be achieved through the mass vaccination of dogs, but maintaining the critical threshold of vaccination coverage for herd immunity in these populations is hampered by their rapid turnover. Knowledge of the population dynamics of free-roaming dog populations can inform effective planning and implementation of mass dog vaccination campaigns to control rabies. Methodology/Principal Findings We implemented a health and demographic surveillance system in dogs that monitored the entire owned dog population within a defined geographic area in a community in Mpumalanga Province, South Africa. We quantified demographic rates over a 24-month period, from 1st January 2012 through 1st January 2014, and assessed their implications for rabies control by simulating the decline in vaccination coverage over time. During this period, the population declined by 10%. Annual population growth rates were +18.6% in 2012 and -24.5% in 2013. Crude annual birth rates (per 1,000 dog-years of observation) were 451 in 2012 and 313 in 2013. Crude annual death rates were 406 in 2012 and 568 in 2013. Females suffered a significantly higher mortality rate in 2013 than males (mortality rate ratio [MRR] = 1.54, 95% CI = 1.28–1.85). In the age class 0–3 months, the mortality rate of dogs vaccinated against rabies was significantly lower than that of unvaccinated dogs (2012: MRR = 0.11, 95% CI = 0.05–0.21; 2013: MRR = 0.31, 95% CI = 0.11–0.69). The results of the simulation showed that achieving a 70% vaccination coverage during annual campaigns would maintain coverage above the critical threshold for at least 12 months. Conclusions and Significance Our findings provide an evidence base for the World Health Organization’s empirically-derived target of 70% vaccination coverage

  11. Using noise to control heterogeneity of isogenic populations in homogenous environments

    NASA Astrophysics Data System (ADS)

    Szymańska, Paulina; Gritti, Nicola; Keegstra, Johannes M.; Soltani, Mohammad; Munsky, Brian

    2015-07-01

    We explore the extent to which the phenotypes of individual, genetically identical cells can be controlled independently from each other using only a single homogeneous environmental input. We show that such control is theoretically impossible if restricted to a deterministic setting, but it can be achieved readily if one exploits heterogeneities introduced at the single-cell level due to stochastic fluctuations in gene regulation. Using stochastic analyses of a bistable genetic toggle switch, we develop a control strategy that maximizes the chances that a chosen cell will express one phenotype, while the rest express another. The control mechanism uses UV radiation to enhance identically protein degradation in all cells. Control of individual cells is made possible only by monitoring stochastic protein fluctuations and applying UV control at favorable times and levels. For two identical cells, our stochastic control law can drive protein expression of a chosen cell above its neighbor with a better than 99% success rate. In a population of 30 identical cells, we can drive a given cell to remain consistently within the top 20%. Although cellular noise typically impairs predictability for biological responses, our results show that it can also simultaneously improve controllability for those same responses.

  12. Using noise to control heterogeneity of isogenic populations in homogenous environments

    PubMed Central

    Szymańska, Paulina; Gritti, Nicola; Keegstra, Johannes M.; Soltani, Mohammad; Munsky, Brian

    2015-01-01

    We explore the extent to which the phenotypes of individual, genetically identical cells can be controlled independently from each other using only a single homogeneous environmental input. We show that such control is theoretically impossible if restricted to a deterministic setting, but it can be achieved readily if one exploits heterogeneities introduced at the single-cell level due to stochastic fluctuations in gene regulation. Using stochastic analyses of a bistable genetic toggle switch, we develop a control strategy that maximizes the chances that a chosen cell will express one phenotype, while the rest express another. The control mechanism uses UV radiation to enhance identically protein degradation in all cells. Control of individual cells is made possible only by monitoring stochastic protein fluctuations and applying UV control at favorable times and levels. For two identical cells, our stochastic control law can drive protein expression of a chosen cell above its neighbor with a better than 99% success rate. In a population of 30 identical cells, we can drive a given cell to remain consistently within the top 20%. Although cellular noise typically impairs predictability for biological responses, our results show that it can also simultaneously improve controllability for those same responses. PMID:26086389

  13. Using population genetic tools to develop a control strategy for feral cats (Felis catus) in Hawai'i

    USGS Publications Warehouse

    Hansen, H.; Hess, S.C.; Cole, D.; Banko, P.C.

    2007-01-01

    Population genetics can provide information about the demographics and dynamics of invasive species that is beneficial for developing effective control strategies. We studied the population genetics of feral cats on Hawai'i Island by microsatellite analysis to evaluate genetic diversity and population structure, assess gene flow and connectivity among three populations, identify potential source populations, characterise population dynamics, and evaluate sex-biased dispersal. High genetic diversity, low structure, and high number of migrants per generation supported high gene flow that was not limited spatially. Migration rates revealed that most migration occurred out of West Mauna Kea. Effective population size estimates indicated increasing cat populations despite control efforts. Despite high gene flow, relatedness estimates declined significantly with increased geographic distance and Bayesian assignment tests revealed the presence of three population clusters. Genetic structure and relatedness estimates indicated male-biased dispersal, primarily from Mauna Kea, suggesting that this population should be targeted for control. However, recolonisation seems likely, given the great dispersal ability that may not be inhibited by barriers such as lava flows. Genetic monitoring will be necessary to assess the effectiveness of future control efforts. Management of other invasive species may benefit by employing these population genetic tools. ?? CSIRO 2007.

  14. Utilitarian prioritization of radiation oncology patients based on maximization of population tumour control

    NASA Astrophysics Data System (ADS)

    Ebert, M. A.; Li, W.; Jennings, L.; Kearvell, R.; Bydder, S.

    2013-06-01

    An objective method for establishing patient prioritization in the context of a radiotherapy waiting list is investigated. This is based on a utilitarian objective, being the greatest probability of local tumour control in the population of patients. A numerical simulation is developed and a clinical patient case-mix is used to determine the influence of the characteristics of the patient population on resulting optimal patient scheduling. With the utilitarian objective, large gains in tumour control probability (TCP) can be achieved for individuals or cohorts by prioritizing patients for that fraction of the patient population with relatively small sacrifices in TCP for a smaller fraction of the population. For a waiting list in steady state with five patients per day commencing treatment and leaving the list (and so with five patients per day entering the list), and a mean wait time of 35 days and a maximum of 90 days, optimized wait times ranged from a mean of one day for patients with tumour types with short effective doubling times to a mean of 66.9 days for prostate cancer patients. It is found that, when seeking the optimal daily order of patients on the waiting list in a constrained simulation, the relative rather than absolute value of TCP is the determinant of the resulting optimal waiting times. An increase in the mean waiting time mostly influences (increases) the optimal waiting times of patients with fast-growing tumours. The proportional representation of groups (separated by tumour type) in the patient population has an influence on the resulting distribution of optimal waiting times for patients in those groups, though has only a minor influence on the optimal mean waiting time for each group.

  15. Utilitarian prioritization of radiation oncology patients based on maximization of population tumour control.

    PubMed

    Ebert, M A; Li, W; Jennings, L; Kearvell, R; Bydder, S

    2013-06-21

    An objective method for establishing patient prioritization in the context of a radiotherapy waiting list is investigated. This is based on a utilitarian objective, being the greatest probability of local tumour control in the population of patients. A numerical simulation is developed and a clinical patient case-mix is used to determine the influence of the characteristics of the patient population on resulting optimal patient scheduling. With the utilitarian objective, large gains in tumour control probability (TCP) can be achieved for individuals or cohorts by prioritizing patients for that fraction of the patient population with relatively small sacrifices in TCP for a smaller fraction of the population. For a waiting list in steady state with five patients per day commencing treatment and leaving the list (and so with five patients per day entering the list), and a mean wait time of 35 days and a maximum of 90 days, optimized wait times ranged from a mean of one day for patients with tumour types with short effective doubling times to a mean of 66.9 days for prostate cancer patients. It is found that, when seeking the optimal daily order of patients on the waiting list in a constrained simulation, the relative rather than absolute value of TCP is the determinant of the resulting optimal waiting times. An increase in the mean waiting time mostly influences (increases) the optimal waiting times of patients with fast-growing tumours. The proportional representation of groups (separated by tumour type) in the patient population has an influence on the resulting distribution of optimal waiting times for patients in those groups, though has only a minor influence on the optimal mean waiting time for each group.

  16. Tuberculosis awareness in Gezira, Sudan: knowledge, attitude and practice case-control survey.

    PubMed

    Suleiman, M M A; Sahal, N; Sodemann, M; Elsony, A; Aro, A R

    2014-03-13

    This case-control study aimed to assess tuberculosis (TB) awareness and its associated sociodemographic characteristics in Gezira, Sudan. New smear-positive TB patients registered in Gezira in 2010 (n = 425) and age-matched controls who attended the same health facilities for other reasons (n = 850) formed the study sample. Awareness was measured using a modified standard World Health Organization TB knowledge, attitude and practice instrument. There was no significant difference between TB cases and the controls in overall levels of TB awareness. About two-thirds of TB cases and controls had good TB awareness. Respondents' sex was associated with awareness among the controls. Age, level of education, type of residence and type of occupation were significantly associated with TB awareness, whereas marital status had no effect. The good level of TB awareness found among TB cases and controls is a baseline for further TB awareness-raising among the Gezira population.

  17. Mitigating amphibian disease: strategies to maintain wild populations and control chytridiomycosis

    PubMed Central

    2011-01-01

    Background Rescuing amphibian diversity is an achievable conservation challenge. Disease mitigation is one essential component of population management. Here we assess existing disease mitigation strategies, some in early experimental stages, which focus on the globally emerging chytrid fungus Batrachochytrium dendrobatidis. We discuss the precedent for each strategy in systems ranging from agriculture to human medicine, and the outlook for each strategy in terms of research needs and long-term potential. Results We find that the effects of exposure to Batrachochytrium dendrobatidis occur on a spectrum from transient commensal to lethal pathogen. Management priorities are divided between (1) halting pathogen spread and developing survival assurance colonies, and (2) prophylactic or remedial disease treatment. Epidemiological models of chytridiomycosis suggest that mitigation strategies can control disease without eliminating the pathogen. Ecological ethics guide wildlife disease research, but several ethical questions remain for managing disease in the field. Conclusions Because sustainable conservation of amphibians in nature is dependent on long-term population persistence and co-evolution with potentially lethal pathogens, we suggest that disease mitigation not focus exclusively on the elimination or containment of the pathogen, or on the captive breeding of amphibian hosts. Rather, successful disease mitigation must be context specific with epidemiologically informed strategies to manage already infected populations by decreasing pathogenicity and host susceptibility. We propose population level treatments based on three steps: first, identify mechanisms of disease suppression; second, parameterize epizootiological models of disease and population dynamics for testing under semi-natural conditions; and third, begin a process of adaptive management in field trials with natural populations. PMID:21496358

  18. Reduced Population Control of an Insect Pest in Managed Willow Monocultures

    PubMed Central

    Dalin, Peter; Kindvall, Oskar; Björkman, Christer

    2009-01-01

    Background There is a general belief that insect outbreak risk is higher in plant monocultures than in natural and more diverse habitats, although empirical studies investigating this relationship are lacking. In this study, using density data collected over seven years at 40 study sites, we compare the temporal population variability of the leaf beetle Phratora vulgatissima between willow plantations and natural willow habitats. Methodology/Principal Findings The study was conducted in 1999–2005. The density of adult P. vulgatissima was estimated in the spring every year by a knock-down sampling technique. We used two measures of population variability, CV and PV, to compare temporal variations in leaf beetle density between plantation and natural habitat. Relationships between density and variability were also analyzed to discern potential underlying processes behind stability in the two systems. The results showed that the leaf beetle P. vulgatissima had a greater temporal population variability and outbreak risk in willow plantations than in natural willow habitats. We hypothesize that the greater population stability observed in the natural habitat was due to two separate processes operating at different levels of beetle density. First, stable low population equilibrium can be achieved by the relatively high density of generalist predators observed in natural stands. Second, stable equilibrium can also be imposed at higher beetle density due to competition, which occurs through depletion of resources (plant foliage) in the natural habitat. In willow plantations, competition is reduced mainly because plants grow close enough for beetle larvae to move to another plant when foliage is consumed. Conclusion/Significance To our knowledge, this is the first empirical study confirming that insect pest outbreak risk is higher in monocultures. The study suggests that comparative studies of insect population dynamics in different habitats may improve our ability to

  19. Population control of an overabundant species achieved through consecutive anthropogenic perturbations.

    PubMed

    Payo-Payo, Ana; Oro, Daniel; Igual, José Manuel; Jover, Lluis; Sanpera, Carolina; Tavecchia, Giacomo

    2015-12-01

    The control of overabundant vertebrates is often problematic. Much work has focused on population-level responses and overabundance due to anthropogenic subsidies. However, far less work has been directed at investigating responses following the removal of subsidies. We investigate the consequences of two consecutive perturbations, the closure of a landfill and an inadvertent poisoning event, on the trophic ecology (δ13C, δ15N, and δ34S), survival, and population size of an overabundant generalist seabird species, the Yellow-legged Gull (Larus michahellis). We expected that the landfill closure would cause a strong dietary shift and the inadvertent poisoning a decrease in gull population size. As a long-lived species, we also anticipated adult survival to be buffered against the decrease in food availability but not against the inadvertent poisoning event. Stable isotope analysis confirmed the dietary shift towards marine resources after the disappearance of the landfill. Although the survival model was inconclusive, it did suggest that the perturbations had a negative effect on survival, which was followed by a recovery back to average values. Food limitation likely triggered dispersal to other populations, while poisoning may have increased mortality; these two processes were likely responsible for the large fall in population size that occurred after the two consecutive perturbations. Life-history theory suggests that perturbations may encourage species to halt existing breeding investment in order to ensure future survival. However, under strong perturbation pulses the resilience threshold might be surpassed and changes in population density can arise. Consecutive perturbations may effectively manage overabundant species. PMID:26910951

  20. Endoscopic Vasectomy of Male Feral Pigeons (Columba livia) as a Possible Method of Population Control.

    PubMed

    Heiderich, Elisabeth; Schildger, Bernd; Lierz, Michael

    2015-03-01

    To evaluate whether single-entry endoscopic vasectomy of male feral pigeons (Columba livia) significantly reduced fertility and would potentially be valuable for control of feral pigeon populations, 252 male feral pigeons were caught in the city of Berne and endoscopically vasectomized. In this procedure, approximately 1 cm of the deferent duct was removed bilaterally. Rapid, uneventful recoveries occurred in 94% (237/252) of the pigeons, whereas 6% (15/252) died because of complications associated with the procedure, consisting of perforation of the ureter (9/15), major hemorrhage (5/15), and respiratory arrest (1/15). Mean anesthesia time was 23±6 minutes. The vasectomized males were habituated to 2 pigeon houses together with fertile females. Another pigeon house with fertile pairs acted as control. All eggs laid were candled weekly to assess fertility. In the 2 pigeon houses with vasectomized males, the mean fertilization rate was 0.9% (5/563), while in the control pigeon house, the rate was 100% (39/39). The results indicate that endoscopic vasectomy of male feral pigeons may be a promising tool for field control of feral pigeon populations, especially in combination with other methods such as pigeon houses. PMID:25867661

  1. Aedes aegypti (Diptera: Culicidae): monitoring of populations to improve control strategies in Argentina.

    PubMed

    Masuh, Héctor; Seccacini, Emilia; Zerba, Eduardo; Licastro, Susana A

    2008-06-01

    To study the seasonal fluctuations of populations of Aedes aegypti (L.), to improve control strategies, or to monitor chemical control interventions, a lightweight, inexpensive ovitrap made of black plastic, pail-shaped, stackable, and provided with a wood tongue depressor was used. Field assays were performed in the northeast and northwest part of Argentina. In a 1-year trial performed in Tartagal (Salta), almost 100% of the ovitraps were highly positive, collecting a total of 1,000/2,000 eggs during March and the first part of April. A focal treatment in the corresponding neighborhood, performed at this time, immediately began to reduce positive ovitraps in spite of the high temperatures registered, rising again in November after winter season. Another field trial was performed in the whole urban area of Iguazú (Misiones). Mosquito populations were evaluated after three weekly ultra low volume (ULV) applications with an EC formulation of permethrin in water. The number of positive ovitraps diminished from 49% to 10% after the treatments. The last one performed in Wanda (Misiones) showed that positive ovitraps inside the dwellings aided in determining reinfestation rates after an intervention with a smoke-generating formulation containing beta-cypermethrin. The work performed in three different situations in urban areas at high risk of dengue can be considered a preliminary assay to establish the effective performance of simple ovitraps, allowing the Vector Control Service of the Argentinian Ministry of Health its use to improve surveillance and control strategies. PMID:18344071

  2. Tobacco control policies and smoking in a population of low education women, 1992–2002

    PubMed Central

    Levy, David T; Mumford, Elizabeth A; Compton, Christine

    2006-01-01

    Study objective To examine recent trends and the role of tobacco control policies associated with smoking among women of low socioeconomic status. Design Using four waves of the nationally representative tobacco use supplement to the current population survey (TUS‐CPS)—(1992–2002), the study examined trends and used multivariate logistic models of smoking prevalence among low education women to examine the role of cigarette prices, clean air regulations, and tobacco control media campaigns, while controlling for other personal characteristics. Setting USA. Participants Women ages 18 and older who report not having completed high school, compared with other women with greater educational attainment and men ages 18 and older with less than a high school degree. Main results Smoking among low education women declined at a greater rate over the study period than among more highly educated women, in contrast with trends of earlier periods. Low education women were found to be particularly responsive to media messages as well as price, especially in comparison with high education women. Conclusions The relation between health and socioeconomic status is not immutable; selected tobacco control policies, such as tax increases and media campaigns targeting low education women, may make inroads in reducing the smoking prevalence of this population. PMID:17708007

  3. The (Non)Effects of Lethal Population Control on the Diet of Australian Dingoes

    PubMed Central

    Allen, Benjamin L.; Leung, Luke K.-P.

    2014-01-01

    Top-predators contribute to ecosystem resilience, yet individuals or populations are often subject to lethal control to protect livestock, managed game or humans from predation. Such management actions sometimes attract concern that lethal control might affect top-predator function in ways ultimately detrimental to biodiversity conservation. The primary function of a predator is predation, which is often investigated by assessing their diet. We therefore use data on prey remains found in 4,298 Australian dingo scats systematically collected from three arid sites over a four year period to experimentally assess the effects of repeated broad-scale poison-baiting programs on dingo diet. Indices of dingo dietary diversity and similarity were either identical or near-identical in baited and adjacent unbaited treatment areas in each case, demonstrating no control-induced change to dingo diets. Associated studies on dingoes' movement behaviour and interactions with sympatric mesopredators were similarly unaffected by poison-baiting. These results indicate that mid-sized top-predators with flexible and generalist diets (such as dingoes) may be resilient to ongoing and moderate levels of population control without substantial alteration of their diets and other related aspects of their ecological function. PMID:25243466

  4. Insulation workers in Belfast. 1. Comparison of a random sample with a control population1

    PubMed Central

    Wallace, William F. M.; Langlands, Jean H. M.

    1971-01-01

    Wallace, W. F. M., and Langlands, J. H. M. (1971).Brit. J. industr. Med.,28, 211-216. Insulation workers in Belfast. 1. Comparison of a random sample with a control population. A sample of 50 men was chosen at random from the population of asbestos insulators in Belfast and matched with a control series of men of similar occupational group with respect to age, height, and smoking habit. Significantly more of the insulators complained of cough and sputum and had basal rales on examination. Clubbing was assessed by means of measurements of the hyponychial angle of both index fingers. These angles were significantly greater in the group of insulators. Twenty-one insulators had ϰ-rays which showed pleural calcification with or without pulmonary fibrosis; one control ϰ-ray showed pulmonary fibrosis. The insulators had no evidence of airways obstruction but static lung volume was reduced and their arterial oxygen tension was lower than that of the controls and their alveolar-arterial oxygen gradient was greater. PMID:5557841

  5. The (non)effects of lethal population control on the diet of Australian dingoes.

    PubMed

    Allen, Benjamin L; Leung, Luke K-P

    2014-01-01

    Top-predators contribute to ecosystem resilience, yet individuals or populations are often subject to lethal control to protect livestock, managed game or humans from predation. Such management actions sometimes attract concern that lethal control might affect top-predator function in ways ultimately detrimental to biodiversity conservation. The primary function of a predator is predation, which is often investigated by assessing their diet. We therefore use data on prey remains found in 4,298 Australian dingo scats systematically collected from three arid sites over a four year period to experimentally assess the effects of repeated broad-scale poison-baiting programs on dingo diet. Indices of dingo dietary diversity and similarity were either identical or near-identical in baited and adjacent unbaited treatment areas in each case, demonstrating no control-induced change to dingo diets. Associated studies on dingoes' movement behaviour and interactions with sympatric mesopredators were similarly unaffected by poison-baiting. These results indicate that mid-sized top-predators with flexible and generalist diets (such as dingoes) may be resilient to ongoing and moderate levels of population control without substantial alteration of their diets and other related aspects of their ecological function. PMID:25243466

  6. Endoscopic Vasectomy of Male Feral Pigeons (Columba livia) as a Possible Method of Population Control.

    PubMed

    Heiderich, Elisabeth; Schildger, Bernd; Lierz, Michael

    2015-03-01

    To evaluate whether single-entry endoscopic vasectomy of male feral pigeons (Columba livia) significantly reduced fertility and would potentially be valuable for control of feral pigeon populations, 252 male feral pigeons were caught in the city of Berne and endoscopically vasectomized. In this procedure, approximately 1 cm of the deferent duct was removed bilaterally. Rapid, uneventful recoveries occurred in 94% (237/252) of the pigeons, whereas 6% (15/252) died because of complications associated with the procedure, consisting of perforation of the ureter (9/15), major hemorrhage (5/15), and respiratory arrest (1/15). Mean anesthesia time was 23±6 minutes. The vasectomized males were habituated to 2 pigeon houses together with fertile females. Another pigeon house with fertile pairs acted as control. All eggs laid were candled weekly to assess fertility. In the 2 pigeon houses with vasectomized males, the mean fertilization rate was 0.9% (5/563), while in the control pigeon house, the rate was 100% (39/39). The results indicate that endoscopic vasectomy of male feral pigeons may be a promising tool for field control of feral pigeon populations, especially in combination with other methods such as pigeon houses.

  7. Economic-demographic interactions and the impact of investments in population control.

    PubMed

    Paqueo, V B

    1981-01-01

    The interaction between economic and demographic factors in the Philippines was examined, analyzing the effects of investment in fertility control on the birthrate, population size, and such economic variables as gross national product (GNP), wage rate, and family income. A family planning model that was constructed and is used to project population program cost and births prevented is grafted to and simulated with a larger economic/demographic model. The simulation results are anayzed. The economic demographic model to which the family planning subsystem was grafted is a modified version of the model constructed by Encarnacion et al. (1974). It is basically a neoclassical model, a closed economy in which the real wage rate is determined by the intersection of the demand and supply of labor. The demand for labor is derived from a Cobb-Douglas production function on the assumption that labor is paid the value of its margin product, and the labor supply is determined by age and sex specific labor force participation rates and population. Capital accumulation is influenced by population size through its effect on government and private consumption expe nditures. Fertility rate is determined by duration of marriage and the level and distribution of family incomes. The model was used to develop projections from 1970 through 2000. Results show that the effects on per capital income and real wage rate seem significant, yet family income appears largely unaffected and the effect on the traditional investment to output ratio (I/Y) seems minimal. One of the outcomes of the projection without family planning is that, if the economy were to depend solely on its own savings, the average annual rate of growth of gross national product (GNP) would be only about 4.32%, which is less than the historical growth rate of 6% and the present government longterm target of 8%. The result suggests that foreign investments and loans would have to play an increasingly important role in the

  8. Postural control and detection of slip/fall initiation in the elderly population.

    PubMed

    Kim, B J; Robinson, Charles J

    2005-07-15

    One of the common causes of morbidity and mortality in workplaces is related to slips or falls. Reaction to external disturbances, such as slips or falls, requires a process of perturbation detection and control of motion changes. Postural control is a common mechanism to compensate unexpected displacements of the body. The ability of postural control diminishes with ageing or neuropathy. In this study, two controlled groups, diabetics and non-diabetics in the elderly population, were investigated to compare how different postural control mechanisms would relate to the detection of perturbation and regain of balance. The ultra-low-vibration Sliding Linear Investigative Platform for Analyzing Lower Limb Stability SYSTEM was used to measure the biomechanical changes of posture and perturbation detection. In phase 1 of the analysis, static measures during quiet standing were considered to investigate the relationship between postural stability and perturbation detection capability. In phase 2 of the analysis, dynamic measures during an occurrence of perturbation were analysed. Statistical tests and linear logistic regression models were applied to find differences of postural control mechanisms and to build a predictive model for perturbation detection quantitatively. It is anticipated that the results of this study will contribute to more comprehensive understanding of postural control mechanisms and design of slip/fall prevention programmes.

  9. De Novo Malignancy Post Liver Transplantation: A Single Center, Population Controlled Study

    PubMed Central

    Chatrath, Hemant; Berman, Kenneth; Vuppalanchi, Raj; Slaven, James; Kwo, Paul; Tector, A Joseph; Chalasani, Naga; Ghabril, Marwan

    2013-01-01

    Background With the growing numbers of liver transplant recipients, it is increasingly important to understand the risks of de novo malignancy after liver transplantation. Aim To characterize the incidence of de novo malignancy after liver transplantation compared to a control non-transplant population. Methods We studied 534 Indiana state residents undergoing liver transplantation at our center between 1997 and 2004, followed through August 2010 The incidence and predictors of malignancy were determined. The standardized incidence ratio (SIR) of cancer in our cohort was compared to age, gender and period matched state population using the Indiana State Cancer Registry. Results After a mean follow up of 5.7 ± 3.2 years, 73 patients (13.7%) developed 80 cancers, with 5 and 10 year incidence rates of 11.7%, and 24.8%, respectively. These included 24 (30%) skin, 16 (20%) hematologic and 40 (50%) solid tumors. The most common solid cancers were aerodigestive. Compared to matched state population, liver transplant recipients had significantly higher incidence of all cancers (SIR:3.1, 95%CI:2.9–3.2), skin (melanoma) (SIR:5.8, 95%CI:4.7–7.0), hematologic (SIR:7.1, 95%CI:6.3–8.0), and solid (SIR:2.7, 95%CI:2.5–2.8) tumors. Conclusion There is a significantly increased risk of de novo malignancies after liver transplantation, highlighting the need for surveillance strategies in this population. PMID:23808800

  10. Population exposure to power-frequency fields: concepts, components, and control

    SciTech Connect

    Florig, H.K.

    1986-01-01

    There are many sources of population exposures to power-frequency (50/60 Hz) electric and magnetic fields including household appliances and wiring, neighborhood distribution circuits, and high-voltage transmission lines. Bioeffects studies were unable to demonstrate that exposures to power-frequency fields can affect public health. Researcher have likewise been unable to show that the health effects of such exposures are negligible. State and federal regulatory agencies are, therefore, grappling with questions of whether and how to regulate the sitting or design of new extra high-voltage transmission lines so as to control the ground-level fields to which people are exposed. The purpose of this dissertation is to illuminate some of the exposure-related aspects of these question. A taxonomy of the relationship between field encounter and effect is developed to clarify the meaning of terms such as exposure and dose in the power-frequency context. The major inputs to models of population dose from power-frequency electric fields are identified. The inputs that contribute most to uncertainty in population dose are shown to be the population distribution around overhead lines, the degree to which various objects shield people from overhead line electric fields, and the body currents that are induced by the non-uniform fields associated with appliances and other indoor sources.

  11. Management and control of microbial populations: development in LSS of missions of different durations

    NASA Astrophysics Data System (ADS)

    Somova, L. A.

    The problem of interaction between man and microorganisms in closed habitats is an inalienable part of the whole problem of co-existence between macro- and microorganisms. Concerning the support of human life in closed habitat, we can, conventionally, divide microorganisms, acting in LSS into three groups: useful, neutral and harmful. The tasks, for human beings for optimal coexistence with micro habitants seem to be trivial: 1) to increase the activity of useful forms, 2) decrease the activity harmful forms, 3) not allow the neutral forms to become the harmful ones and even to help them to gain useful activity. The task of efficient management and control of microbial population's development in LSS highly depends on mission duration. As for short-term missions without recycling, the proper hygienic procedures are developed. For longer missions, the probability of transformation of the neutral forms into the harmful ones is becoming more dangerous. The LSS for long-term missions are to use cycling-recycling systems, including biological recycling. In these systems, microbial populations should be the most useful and active agents. Some problems of microbial populations control and management are discussed in the paper.

  12. Management and control of microbial populations' development in LSS of missions of different durations.

    PubMed

    Somova, L A; Pechurkin, N S

    2005-01-01

    The problem of interaction between man and microorganisms in closed habitats is an inextricable part of the whole problem of co-existence between macro- and microorganisms. Concerning the support of human life in closed habitat, we can, conventionally, divide microorganisms, acting in life support system (LSS) into three groups: useful, neutral and harmful. The tasks, for human beings for optimal coexistence with microhabitants seem to be trivial: (1) to increase the activity of useful forms, (2) decrease the activity harmful forms, (3) not allow the neutral forms to become the harmful ones and even to help them to gain useful activity. The task of efficient management and control of microbial population's development in LSS highly depends on mission duration. As for short-term missions without recycling, the proper hygienic procedures are developed. For longer missions, the probability of transformation of the neutral forms into the harmful ones is becoming more dangerous. The LSS for long-term missions are to use cycling-recycling systems, including system with biological recycling. In these systems, microbial populations as regenerative link should be useful and active agents. Some problems of microbial populations control and management are discussed in the paper. PMID:16175696

  13. Costs Analysis of a Population Level Rabies Control Programme in Tamil Nadu, India

    PubMed Central

    Abbas, Syed Shahid; Kakkar, Manish; Rogawski, Elizabeth Tacket

    2014-01-01

    The study aimed to determine costs to the state government of implementing different interventions for controlling rabies among the entire human and animal populations of Tamil Nadu. This built upon an earlier assessment of Tamil Nadu's efforts to control rabies. Anti-rabies vaccines were made available at all health facilities. Costs were estimated for five different combinations of animal and human interventions using an activity-based costing approach from the provider perspective. Disease and population data were sourced from the state surveillance data, human census and livestock census. Program costs were extrapolated from official documents. All capital costs were depreciated to estimate annualized costs. All costs were inflated to 2012 Rupees. Sensitivity analysis was conducted across all major cost centres to assess their relative impact on program costs. It was found that the annual costs of providing Anti-rabies vaccine alone and in combination with Immunoglobulins was $0.7 million (Rs 36 million) and $2.2 million (Rs 119 million), respectively. For animal sector interventions, the annualised costs of rolling out surgical sterilisation-immunization, injectable immunization and oral immunizations were estimated to be $ 44 million (Rs 2,350 million), $23 million (Rs 1,230 million) and $ 11 million (Rs 590 million), respectively. Dog bite incidence, health systems coverage and cost of rabies biologicals were found to be important drivers of costs for human interventions. For the animal sector interventions, the size of dog catching team, dog population and vaccine costs were found to be driving the costs. Rabies control in Tamil Nadu seems a costly proposition the way it is currently structured. Policy makers in Tamil Nadu and other similar settings should consider the long-term financial sustainability before embarking upon a state or nation-wide rabies control programme. PMID:24587471

  14. Costs analysis of a population level rabies control programme in Tamil Nadu, India.

    PubMed

    Abbas, Syed Shahid; Kakkar, Manish; Rogawski, Elizabeth Tacket

    2014-02-01

    The study aimed to determine costs to the state government of implementing different interventions for controlling rabies among the entire human and animal populations of Tamil Nadu. This built upon an earlier assessment of Tamil Nadu's efforts to control rabies. Anti-rabies vaccines were made available at all health facilities. Costs were estimated for five different combinations of animal and human interventions using an activity-based costing approach from the provider perspective. Disease and population data were sourced from the state surveillance data, human census and livestock census. Program costs were extrapolated from official documents. All capital costs were depreciated to estimate annualized costs. All costs were inflated to 2012 Rupees. Sensitivity analysis was conducted across all major cost centres to assess their relative impact on program costs. It was found that the annual costs of providing Anti-rabies vaccine alone and in combination with Immunoglobulins was $0.7 million (Rs 36 million) and $2.2 million (Rs 119 million), respectively. For animal sector interventions, the annualised costs of rolling out surgical sterilisation-immunization, injectable immunization and oral immunizations were estimated to be $ 44 million (Rs 2,350 million), $23 million (Rs 1,230 million) and $ 11 million (Rs 590 million), respectively. Dog bite incidence, health systems coverage and cost of rabies biologicals were found to be important drivers of costs for human interventions. For the animal sector interventions, the size of dog catching team, dog population and vaccine costs were found to be driving the costs. Rabies control in Tamil Nadu seems a costly proposition the way it is currently structured. Policy makers in Tamil Nadu and other similar settings should consider the long-term financial sustainability before embarking upon a state or nation-wide rabies control programme. PMID:24587471

  15. Costs analysis of a population level rabies control programme in Tamil Nadu, India.

    PubMed

    Abbas, Syed Shahid; Kakkar, Manish; Rogawski, Elizabeth Tacket

    2014-02-01

    The study aimed to determine costs to the state government of implementing different interventions for controlling rabies among the entire human and animal populations of Tamil Nadu. This built upon an earlier assessment of Tamil Nadu's efforts to control rabies. Anti-rabies vaccines were made available at all health facilities. Costs were estimated for five different combinations of animal and human interventions using an activity-based costing approach from the provider perspective. Disease and population data were sourced from the state surveillance data, human census and livestock census. Program costs were extrapolated from official documents. All capital costs were depreciated to estimate annualized costs. All costs were inflated to 2012 Rupees. Sensitivity analysis was conducted across all major cost centres to assess their relative impact on program costs. It was found that the annual costs of providing Anti-rabies vaccine alone and in combination with Immunoglobulins was $0.7 million (Rs 36 million) and $2.2 million (Rs 119 million), respectively. For animal sector interventions, the annualised costs of rolling out surgical sterilisation-immunization, injectable immunization and oral immunizations were estimated to be $ 44 million (Rs 2,350 million), $23 million (Rs 1,230 million) and $ 11 million (Rs 590 million), respectively. Dog bite incidence, health systems coverage and cost of rabies biologicals were found to be important drivers of costs for human interventions. For the animal sector interventions, the size of dog catching team, dog population and vaccine costs were found to be driving the costs. Rabies control in Tamil Nadu seems a costly proposition the way it is currently structured. Policy makers in Tamil Nadu and other similar settings should consider the long-term financial sustainability before embarking upon a state or nation-wide rabies control programme.

  16. PAN-811 inhibits oxidative stress-induced cell death of human Alzheimer's disease-derived and age-matched olfactory neuroepithelial cells via suppression of intracellular reactive oxygen species.

    PubMed

    Nelson, Valery M; Dancik, Chantée M; Pan, Weiying; Jiang, Zhi-Gang; Lebowitz, Michael S; Ghanbari, Hossein A

    2009-01-01

    Oxidative stress plays a significant role in neurotoxicity associated with a variety of neurodegenerative diseases including Alzheimer's disease (AD). Increased oxidative stress has been shown to be a prominent and early feature of vulnerable neurons in AD. Olfactory neuroepithelial cells are affected at an early stage. Exposure to oxidative stress induces the accumulation of intracellular reactive oxygen species (ROS), which in turn causes cell damage in the form of protein, lipid, and DNA oxidations. Elevated ROS levels are also associated with increased deposition of amyloid-beta and formation of senile plaques, a hallmark of the AD brain. If enhanced ROS exceeds the basal level of cellular protective mechanisms, oxidative damage and cell death will result. Therefore, substances that can reduce oxidative stress are sought as potential drug candidates for treatment or preventative therapy of neurodegenerative diseases such as AD. PAN-811, also known as 3-aminopyridine-2-carboxaldehyde thiosemicarbazone or Triapine, is a small lipophilic compound that is currently being investigated in several Phase II clinical trials for cancer therapy due to its inhibition of ribonucleotide reductase activity. Here we show PAN-811 to be effective in preventing or reducing ROS accumulation and the resulting oxidative damages in both AD-derived and age-matched olfactory neuroepithelial cells.

  17. Sociodemographic characteristics of domestic violence in China: a population case-control study.

    PubMed

    Cao, YuPing; Yang, ShiChang; Wang, GuoQiang; Zhang, YaLin

    2014-03-01

    A population case-control study of domestic violence in China was conducted to examine the relationship between individual- and household-level characteristics and violence perpetration and victimization. Demographic comparisons were conducted between perpetrators and victims (n = 624), perpetrators and matched controls (n = 628), and perpetrator households and control households (n = 620). A multivariate model of demographic risk was tested, integrating individual- and household-level correlates of violence perpetration. Compared with victims, perpetrators were more likely to be older, male, and have lower levels of education. In the final model, violence perpetration was more likely among individuals who earned more income, contributed a lower proportion of the household income, had a family member who was unemployed or lived in households with an authoritarian or independent power structure. PMID:24176988

  18. Reported Hearing Impairment in Essential Tremor: A Population-Based Case-Control Study

    PubMed Central

    Benito-León, Julián; Louis, Elan D.; Bermejo-Pareja, Félix

    2008-01-01

    In a population-based sample, we determined whether a larger proportion of essential tremor (ET) cases reported hearing impairment compared with controls. Ninety-six (38.7%) of 248 ET cases versus 1,371 (29.4%) of 4,669 controls (p = 0.002) reported hearing impairment. In a logistic regression analysis adjusted for age, gender, educational level, depressive symptoms, and dementia, participants who reported hearing impairment were 30% more likely to suffer from ET than were controls (odds ratio 1.3; 95% confidence interval 1.01–1.7; p = 0.04). ET seemed to be associated with reported hearing impairment. The basis for this finding, which has been noted in several studies, deserves further exploration. PMID:18073494

  19. Autonomous development of vergence control driven by disparity energy neuron populations.

    PubMed

    Wang, Yiwen; Shi, Bertram E

    2010-03-01

    We present a simple optimization criterion that leads to autonomous development of a sensorimotor feedback loop driven by the neural representation of the depth in the mammalian visual cortex. Our test bed is an active stereo vision system where the vergence angle between the two eyes is controlled by the output of a population of disparity-selective neurons. By finding a policy that maximizes the total response across the neuron population, the system eventually tracks a target as it moves in depth. We characterized the tracking performance of the resulting policy using objects moving both sinusoidally and randomly in depth. Surprisingly, the system can even learn how to track based on stimuli it cannot track: even though the closed loop 3 dB tracking bandwidth of the system is 0.3 Hz, correct tracking policies are learned for input stimuli moving as fast as 0.75 Hz. PMID:19925282

  20. Autonomous development of vergence control driven by disparity energy neuron populations.

    PubMed

    Wang, Yiwen; Shi, Bertram E

    2010-03-01

    We present a simple optimization criterion that leads to autonomous development of a sensorimotor feedback loop driven by the neural representation of the depth in the mammalian visual cortex. Our test bed is an active stereo vision system where the vergence angle between the two eyes is controlled by the output of a population of disparity-selective neurons. By finding a policy that maximizes the total response across the neuron population, the system eventually tracks a target as it moves in depth. We characterized the tracking performance of the resulting policy using objects moving both sinusoidally and randomly in depth. Surprisingly, the system can even learn how to track based on stimuli it cannot track: even though the closed loop 3 dB tracking bandwidth of the system is 0.3 Hz, correct tracking policies are learned for input stimuli moving as fast as 0.75 Hz.

  1. Environmental impact propagated by cross-system subsidy: chronic stream pollution controls riparian spider populations.

    PubMed

    Paetzold, Achim; Smith, Marian; Warren, Philip H; Maltby, Lorraine

    2011-09-01

    Resource subsidies between habitats are common and create the potential for the propagation of environmental impacts across system boundaries. However, recent understanding of the potential for subsidy-mediated cross-system impact propagations is limited and primarily based on passive flows of nutrients and detritus or short-term effects. Here, we assess the effects of sustained alterations in aquatic insect emergence (active subsidy pathway), due to chronic stream pollution, for riparian spiders. The sustained reduction in aquatic insect densities at the polluted reaches resulted in a marked decline in web spider population density and a shift in spider community composition. Our results provide the first evidence that stream pollution can control populations and community structure of terrestrial predators via sustained alterations in aquatic subsidies, emphasizing the role of subtle trophic linkages in the transmission of environmental impacts across ecosystem boundaries.

  2. The Trojan female technique: a novel, effective and humane approach for pest population control.

    PubMed

    Gemmell, Neil J; Jalilzadeh, Aidin; Didham, Raphael K; Soboleva, Tanya; Tompkins, Daniel M

    2013-12-22

    Humankind's ongoing battle with pest species spans millennia. Pests cause or carry disease, damage or consume food crops and other resources, and drive global environmental change. Conventional approaches to pest management usually involve lethal control, but such approaches are costly, of varying efficiency and often have ethical issues. Thus, pest management via control of reproductive output is increasingly considered an optimal solution. One of the most successful such 'fertility control' strategies developed to date is the sterile male technique (SMT), in which large numbers of sterile males are released into a population each generation. However, this approach is time-consuming, labour-intensive and costly. We use mathematical models to test a new twist on the SMT, using maternally inherited mitochondrial (mtDNA) mutations that affect male, but not female reproductive fitness. 'Trojan females' carrying such mutations, and their female descendants, produce 'sterile-male'-equivalents under natural conditions over multiple generations. We find that the Trojan female technique (TFT) has the potential to be a novel humane approach for pest control. Single large releases and relatively few small repeat releases of Trojan females both provided effective and persistent control within relatively few generations. Although greatest efficacy was predicted for high-turnover species, the additive nature of multiple releases made the TFT applicable to the full range of life histories modelled. The extensive conservation of mtDNA among eukaryotes suggests this approach could have broad utility for pest control.

  3. Can tobacco control be transformative? Reducing gender inequity and tobacco use among vulnerable populations.

    PubMed

    Greaves, Lorraine

    2014-01-07

    Tobacco use and exposure is unequally distributed across populations and countries and among women and men. These trends and patterns reflect and cause gender and economic inequities along with negative health impacts. Despite a commitment to gender analysis in the preamble to Framework Convention on Tobacco Control there is much yet to be done to fully understand how gender operates in tobacco control. Policies, program and research in tobacco control need to not only integrate gender, but rather operationalize gender with the goal of transforming gender and social inequities in the course of tobacco control initiatives. Gender transformative tobacco control goes beyond gender sensitive efforts and challenges policy and program developers to apply gender theory in designing their initiatives, with the goal of changing negative gender and social norms and improving social, economic, health and social indicators along with tobacco reduction. This paper outlines what is needed to progress tobacco control in enhancing the status of gendered and vulnerable groups, with a view to reducing gender and social inequities due to tobacco use and exposure.

  4. The Trojan female technique: a novel, effective and humane approach for pest population control.

    PubMed

    Gemmell, Neil J; Jalilzadeh, Aidin; Didham, Raphael K; Soboleva, Tanya; Tompkins, Daniel M

    2013-12-22

    Humankind's ongoing battle with pest species spans millennia. Pests cause or carry disease, damage or consume food crops and other resources, and drive global environmental change. Conventional approaches to pest management usually involve lethal control, but such approaches are costly, of varying efficiency and often have ethical issues. Thus, pest management via control of reproductive output is increasingly considered an optimal solution. One of the most successful such 'fertility control' strategies developed to date is the sterile male technique (SMT), in which large numbers of sterile males are released into a population each generation. However, this approach is time-consuming, labour-intensive and costly. We use mathematical models to test a new twist on the SMT, using maternally inherited mitochondrial (mtDNA) mutations that affect male, but not female reproductive fitness. 'Trojan females' carrying such mutations, and their female descendants, produce 'sterile-male'-equivalents under natural conditions over multiple generations. We find that the Trojan female technique (TFT) has the potential to be a novel humane approach for pest control. Single large releases and relatively few small repeat releases of Trojan females both provided effective and persistent control within relatively few generations. Although greatest efficacy was predicted for high-turnover species, the additive nature of multiple releases made the TFT applicable to the full range of life histories modelled. The extensive conservation of mtDNA among eukaryotes suggests this approach could have broad utility for pest control. PMID:24174117

  5. Can Tobacco Control Be Transformative? Reducing Gender Inequity and Tobacco Use among Vulnerable Populations

    PubMed Central

    Greaves, Lorraine

    2014-01-01

    Tobacco use and exposure is unequally distributed across populations and countries and among women and men. These trends and patterns reflect and cause gender and economic inequities along with negative health impacts. Despite a commitment to gender analysis in the preamble to Framework Convention on Tobacco Control there is much yet to be done to fully understand how gender operates in tobacco control. Policies, program and research in tobacco control need to not only integrate gender, but rather operationalize gender with the goal of transforming gender and social inequities in the course of tobacco control initiatives. Gender transformative tobacco control goes beyond gender sensitive efforts and challenges policy and program developers to apply gender theory in designing their initiatives, with the goal of changing negative gender and social norms and improving social, economic, health and social indicators along with tobacco reduction. This paper outlines what is needed to progress tobacco control in enhancing the status of gendered and vulnerable groups, with a view to reducing gender and social inequities due to tobacco use and exposure. PMID:24402065

  6. Population control of exotic rainbow trout in streams of a natural area park

    NASA Astrophysics Data System (ADS)

    Moore, Stephen E.; Larson, Gary L.; Ridley, Bromfield

    1986-03-01

    Expansion of the distribution of exotic rainbow trout is thought to be a leading cause for the decline of native brook trout since the 1930s in Great Smoky Mountains National Park, USA. An experimental rehabilitation project was conducted from 1976 to 1981 using backpack electrofish shockers on four remnant brook trout populations sympatric with rainbow trout. The objectives were to evaluate the effectiveness of the technique to remove the exotic rainbow trout, to determine the population responses by native brook trout, and to evaluate the usefulness of the technique for trout management in the park. Rainbow trout populations were greatly reduced in density after up to six years of electrofishing, but were not eradicated. Rainbow trout recruitment, however, was essentially eliminated. Brook trout populations responded by increasing in density (including young-of-the-year), but rates of recovery differed among streams. The maximum observed densities ir each stream occurred at the end of the project. The findings suggest that electrofishing had a major negative impact on the exotic species, which was followed by positive responses from the native species in the second and third order study streams. The technique would probably be less effective in larger (fourth-order) park streams, but as an eradication tool the technique may have its highest potential in small first order streams. Nonetheless, the technique appears useful for population control without causing undue impacts on native aquatic species, although it is labor intensive, and capture efficiency is greatly influenced by fish size and stream morphology. To completely remove the exotic fish from selected streams, different technologies will have to be explored and developed.

  7. Model-based control of plasma glycemia: Tests on populations of virtual patients.

    PubMed

    Palumbo, P; Pizzichelli, G; Panunzi, S; Pepe, P; De Gaetano, A

    2014-11-01

    Closed-loop devices delivering medical treatments in an automatic fashion clearly require a thorough preliminary phase according to which the proposed control law is tested and validated as realistically as possible, before arranging in vivo experiments in a clinical setting. The present note develops a virtual environment aiming to validate a recently proposed model-based glucose control law on a solid simulation framework. From a theoretical viewpoint, the artificial pancreas has been designed by suitably exploiting a minimal set of delay differential equations modeling the glucose-insulin regulatory system; on the other hand, the validation platform makes use of a different, multi-compartmental model to build up a population of virtual patients. Simulations are carried out by properly addressing the available technological limits and the unavoidable uncertainties in real-time continuous glucose sensors as well as possible malfunctioning on the insulin delivery devices. The results show the robustness of the proposed control law that turns out to be efficient and extremely safe on a heterogenous population of virtual patients.

  8. Rapid increase in contraceptive rate: since 1981 new population control policy.

    PubMed

    1984-03-01

    In December 1981 the government of the Republic of Korea announced new population control policy measures calling for an improvement of the current family planning program management system; institution of a new social and institutional support system to inculcate the small size family norm and to eradicate the parental son preference attitude; strengthening information, education, and communication (IEC) activities; and establishment of close coordination among the government organizations relating to the population programs. As a result of the policy measures, since 1982 there has been a rapid increase in the contraceptive acceptance rate. The number of contraceptive acceptors through the government program increased from 614,100 in 1981 to 1,094,600 in 1983, a 78.3% increase. There has been a marked increase in sterilization and menstrual regulation services. The program achievement for 1983 is equivalent to about 19% of the total eligible women aged 15-44. According to the contraceptive acceptors' coupon analysis, the age of women at the time of contraceptive acceptance through the government program dropped steadily from 31.4 in 1981 to 30.2 in 1983 and their number of children declined from 2.8 to 2.5 during the same period. In line with the new population control policy, several social support measures for the small size family have been strengthened. These include: income tax exemption up to 2 children; corporation tax exemption on expenditure for family planning services to employees; inclusion of population education in the formal school curriculum; and reduction of child delivery charges for sterilization acceptors after 2nd delivery in public hospitals. The 1982 National Family Health Survey revealed that the total fertility rate declined to 2.7 and the contraceptive practice rate of women aged 15-44 increased to 58% in 1982. Yet, in recent years virtually no substantial change in the fertility level and in the contraceptive practice rate has been

  9. The importance of functional form in optimal control solutions of problems in population dynamics

    USGS Publications Warehouse

    Runge, M.C.; Johnson, F.A.

    2002-01-01

    Optimal control theory is finding increased application in both theoretical and applied ecology, and it is a central element of adaptive resource management. One of the steps in an adaptive management process is to develop alternative models of system dynamics, models that are all reasonable in light of available data, but that differ substantially in their implications for optimal control of the resource. We explored how the form of the recruitment and survival functions in a general population model for ducks affected the patterns in the optimal harvest strategy, using a combination of analytical, numerical, and simulation techniques. We compared three relationships between recruitment and population density (linear, exponential, and hyperbolic) and three relationships between survival during the nonharvest season and population density (constant, logistic, and one related to the compensatory harvest mortality hypothesis). We found that the form of the component functions had a dramatic influence on the optimal harvest strategy and the ultimate equilibrium state of the system. For instance, while it is commonly assumed that a compensatory hypothesis leads to higher optimal harvest rates than an additive hypothesis, we found this to depend on the form of the recruitment function, in part because of differences in the optimal steady-state population density. This work has strong direct consequences for those developing alternative models to describe harvested systems, but it is relevant to a larger class of problems applying optimal control at the population level. Often, different functional forms will not be statistically distinguishable in the range of the data. Nevertheless, differences between the functions outside the range of the data can have an important impact on the optimal harvest strategy. Thus, development of alternative models by identifying a single functional form, then choosing different parameter combinations from extremes on the likelihood

  10. Achieving glycemic control in special populations in hospital: perspectives in practice.

    PubMed

    Cheng, Alice Y Y

    2014-04-01

    Achieving and maintaining glycemic control in patients with diabetes admitted to hospital is challenging because of the many competing factors of nutrition, pharmacotherapy and other patient-related and systemic factors. For patients receiving enteral or parenteral feeding, eating irregularly or receiving glucocorticoid therapy, the challenges are even greater. The basic principles to follow when managing glycemia in these populations are as follows: 1) Recognition of those at risk for hyperglycemia; 2) frequent bedside glucose monitoring; 3) a proactive approach with routine insulin administration based on the predicted glucose patterns; 4) constant reassessment of the glycemic status and titration of the routine insulin accordingly.

  11. Accessibility of dog populations for rabies control in Kathmandu valley, Nepal.

    PubMed Central

    Bögel, K.; Joshi, D. D.

    1990-01-01

    The accessibility of dogs in urban areas of Kathmandu valley was measured using the following approaches: determination of the proportion of dogs that bore signs of having been the objects of religious worship and other signs of household association, supplemented by information obtained by interviewing people in the neighbourhood; and the vaccination coverage attained in a rabies control campaign that was preceded by intensive activities to encourage the community to participate. An accessibility rate of 90-95% was determined using the first of these approaches, whereas 75-80% of the total dog population was reached in the vaccination campaign. PMID:2289296

  12. The Trojan female technique: a novel, effective and humane approach for pest population control

    PubMed Central

    Gemmell, Neil J.; Jalilzadeh, Aidin; Didham, Raphael K.; Soboleva, Tanya; Tompkins, Daniel M.

    2013-01-01

    Humankind's ongoing battle with pest species spans millennia. Pests cause or carry disease, damage or consume food crops and other resources, and drive global environmental change. Conventional approaches to pest management usually involve lethal control, but such approaches are costly, of varying efficiency and often have ethical issues. Thus, pest management via control of reproductive output is increasingly considered an optimal solution. One of the most successful such ‘fertility control’ strategies developed to date is the sterile male technique (SMT), in which large numbers of sterile males are released into a population each generation. However, this approach is time-consuming, labour-intensive and costly. We use mathematical models to test a new twist on the SMT, using maternally inherited mitochondrial (mtDNA) mutations that affect male, but not female reproductive fitness. ‘Trojan females’ carrying such mutations, and their female descendants, produce ‘sterile-male’-equivalents under natural conditions over multiple generations. We find that the Trojan female technique (TFT) has the potential to be a novel humane approach for pest control. Single large releases and relatively few small repeat releases of Trojan females both provided effective and persistent control within relatively few generations. Although greatest efficacy was predicted for high-turnover species, the additive nature of multiple releases made the TFT applicable to the full range of life histories modelled. The extensive conservation of mtDNA among eukaryotes suggests this approach could have broad utility for pest control. PMID:24174117

  13. Level of neurotoxic metals in amyotrophic lateral sclerosis: A population-based case-control study.

    PubMed

    Bocca, Beatrice; Forte, Giovanni; Oggiano, Riccardo; Clemente, Simonetta; Asara, Yolande; Peruzzu, Angela; Farace, Cristiano; Pala, Salvatore; Fois, Alessandro Giuseppe; Pirina, Pietro; Madeddu, Roberto

    2015-12-15

    The association between exposure to toxic metals and amyotrophic lateral sclerosis (ALS) was explored in a population-based case-control study in the Sardinia island (Italy), a region characterized by elevated rates of ALS cases. In 34 patients with ALS (mean age, 62 ± 10 years) and 30 controls (mean age, 65 ± 11 years), Al, Cd, Hg, Mn and Pb were determined in blood, hair and urine by sector field inductively coupled mass spectrometry. Results indicated that, in blood, concentrations of Al (p=0.045) and Pb were higher (p=0.026) in ALS patients than in control subjects. In hair, a depletion of Al (p=0.006) and Mn (p=0.032) concentrations in ALS subjects respect to controls was found. In urine, no significant differences between cases and controls were observed. Thus, some metals seemed to be associated with ALS degeneration, but a definitive conclusion is still far considering the multiple risk factors (genetic mutations, environmental toxicants and stressors) involved in the disease. Finally, the interpretation that deregulated metal concentrations can be a consequence of the degenerative process, rather than a cause, is also valid. PMID:26671079

  14. Level of neurotoxic metals in amyotrophic lateral sclerosis: A population-based case-control study.

    PubMed

    Bocca, Beatrice; Forte, Giovanni; Oggiano, Riccardo; Clemente, Simonetta; Asara, Yolande; Peruzzu, Angela; Farace, Cristiano; Pala, Salvatore; Fois, Alessandro Giuseppe; Pirina, Pietro; Madeddu, Roberto

    2015-12-15

    The association between exposure to toxic metals and amyotrophic lateral sclerosis (ALS) was explored in a population-based case-control study in the Sardinia island (Italy), a region characterized by elevated rates of ALS cases. In 34 patients with ALS (mean age, 62 ± 10 years) and 30 controls (mean age, 65 ± 11 years), Al, Cd, Hg, Mn and Pb were determined in blood, hair and urine by sector field inductively coupled mass spectrometry. Results indicated that, in blood, concentrations of Al (p=0.045) and Pb were higher (p=0.026) in ALS patients than in control subjects. In hair, a depletion of Al (p=0.006) and Mn (p=0.032) concentrations in ALS subjects respect to controls was found. In urine, no significant differences between cases and controls were observed. Thus, some metals seemed to be associated with ALS degeneration, but a definitive conclusion is still far considering the multiple risk factors (genetic mutations, environmental toxicants and stressors) involved in the disease. Finally, the interpretation that deregulated metal concentrations can be a consequence of the degenerative process, rather than a cause, is also valid.

  15. [Coordination of governmental and public control in providing sanitary epidemiologic well-being of population and consumers' rights protection].

    PubMed

    Rakitin, I A; Zel'din, A L

    2015-01-01

    The article covers features of govenmental and public control in providing sanitary epidemiologic well-being of population and consumers' rights protection. Based on analysis of contemporary legislation, the authors evaluated terms "control" and "supervision", having different legal nature. The authors determined specific traits and define subjects and objects for public control in relationships aimed to provide sanitary epidemiologic well-being of population, evaluated legislative basis of citizens' claims to Rospotrebnadzor, pointed at difficulties in implementation of public control in connection with necessity to create new organizational and legal mechanisms widening control possibilities.

  16. Control of Xiphinema index populations by fallow plants under greenhouse and field conditions.

    PubMed

    Villate, Laure; Morin, Elisa; Demangeat, Gérard; Van Helden, Maarten; Esmenjaud, Daniel

    2012-06-01

    The dagger nematode Xiphinema index has a high economic impact in vineyards by direct pathogenicity and above all by transmitting the Grapevine fanleaf virus (GFLV). Agrochemicals have been largely employed to restrict the spread of GFLV by reducing X. index populations but are now banned. As an alternative to nematicides, the use of fallow plants between two successive vine crops was assessed. We selected plant species adapted to vineyard soils and exhibiting negative impact on nematodes and we evaluated their antagonistic effect on X. index in greenhouse using artificially infested soil, and in naturally infested vineyard conditions. The screening was conducted with plants belonging to the families Asteraceae (sunflower, marigold, zinnia, and nyjer), Poaceae (sorghum and rye), Fabaceae (white lupin, white melilot, hairy vetch, and alfalfa), Brassicaceae (rapeseed and camelina), and Boraginaceae (phacelia). In the greenhouse controlled assay, white lupin, nyjer, and marigold significantly reduced X. index populations compared with that of bare soil. The vineyard assay, designed to take into account the aggregative pattern of X. index distribution, revealed that marigold and hairy vetch are good candidates as cover crops to reduce X. index populations in vineyard. Moreover, this original experimental design could be applied to manage other soilborne pathogens.

  17. Ecology and control of an introduced population of Southern Watersnakes (Nerodia fasciata) in southern California

    USGS Publications Warehouse

    Reed, Robert; Todd, Brian D; Miano, Oliver J.; Canfield, Mark; Fisher, Robert N.; McMartin, Louanne

    2016-01-01

    Native to the southeastern United States, Southern Watersnakes (Nerodia fasciata) are known from two sites in California, but their ecological impacts are poorly understood. We investigated the ecology of Southern Watersnakes in Machado Lake, Harbor City, Los Angeles County, California, including an assessment of control opportunities. We captured 306 watersnakes as a result of aquatic trapping and hand captures. We captured snakes of all sizes (162–1063 mm snout–vent length [SVL], 3.5–873.3 g), demonstrating the existence of a well-established population. The smallest reproductive female was 490 mm SVL and females contained 12–46 postovulatory embryos (mean  =  21). Small watersnakes largely consumed introduced Western Mosquitofish (Gambusia affinis), while larger snakes specialized on larval and metamorph American Bullfrogs (Lithobates catesbeianus) and Green Sunfish (Lepomis cyanellus). Overall capture per unit effort (CPUE) in traps declined with time during an intensive 76-d trapping bout, but CPUE trends varied considerably among traplines and it is unlikely that the overall decline in CPUE represented a major decrease in the snake population size. Although we found no direct evidence that Southern Watersnakes are affecting native species in Machado Lake, this population may serve as a source for intentional or unintentional transportation of watersnakes to bodies of water containing imperiled native prey species or potential competitors.

  18. Artificial parthenogenesis and control of voltinism to manage transgenic populations in Bombyx mori.

    PubMed

    Grenier, Anne-Marie; Da Rocha, Martine; Jalabert, Audrey; Royer, Corinne; Mauchamp, Bernard; Chavancy, Gérard

    2004-08-01

    In order to improve the management of transformed populations in a routine application of transgenesis technology in Bombyx mori, we modified its mode of reproduction and its voltinism. On one hand, after a stable integration of the gene of interest by transgenesis, it is preferable to maintain this gene in an identical genomic context through successive generations. This can be obtained by artificial parthenogenetic reproduction (ameiotic parthenogenesis) giving isogenic females identical to their transformed mother. On the other hand, it is essential to obtain continuous generations (polyvoltinism) after microinjection, in order to screen positive transgenic insects and study genetics and insertion of the transgene. Thereafter, it is more convenient to store these populations, as diapause eggs before their use in biotechnology application. We obtained such polyvoltine parthenoclones, first by selection for a parthenogenetic character in polyvoltine races, and second, by selection for a polyvoltine character in a parthenogenetic, but diapausing clone of B. mori. As diapause was directly under the control of diapause hormone (DH), we also tested direct injection of DH in female pupae of polyvoltine strains, as well as anti-DH antibody treatment to eliminate diapause in univoltine strains. We discussed the advantages and limitations of these methods and proved the feasibility in obtaining polyvoltine parthenoclones and determining the voltinism in B. mori. These methods would permit us to improve the management of populations used in transgenesis technology.

  19. Behavioral and technological interventions targeting glycemic control in a racially/ethnically diverse population: a randomized controlled trial

    PubMed Central

    2014-01-01

    Background Diabetes self-care by patients has been shown to assist in the reduction of disease severity and associated medical costs. We compared the effectiveness of two different diabetes self-care interventions on glycemic control in a racially/ethnically diverse population. We also explored whether reductions in glycated hemoglobin (HbA1c) will be more marked in minority persons. Methods We conducted an open-label randomized controlled trial of 376 patients with type 2 diabetes aged ≥18 years and whose last measured HbA1c was ≥7.5% (≥58 mmol/mol). Participants were randomized to: 1) a Chronic Disease Self-Management Program (CDSMP; n = 101); 2) a diabetes self-care software on a personal digital assistant (PDA; n = 81); 3) a combination of interventions (CDSMP + PDA; n = 99); or 4) usual care (control; n = 95). Enrollment occurred January 2009-June 2011 at seven regional clinics of a university-affiliated multi-specialty group practice. The primary outcome was change in HbA1c from randomization to 12 months. Data were analyzed using a multilevel statistical model. Results Average baseline HbA1c in the CDSMP, PDA, CDSMP + PDA, and control arms were 9.4%, 9.3%, 9.2%, and 9.2%, respectively. HbA1c reductions at 12 months for the groups averaged 1.1%, 0.7%, 1.1%, and 0.7%, respectively and did not differ significantly from baseline based on the model (P = .771). Besides the participants in the PDA group reporting eating more high-fat foods compared to their counterparts (P < .004), no other significant differences were observed in participants’ diabetes self-care activities. Exploratory sub-analysis did not reveal any marked reductions in HbA1c for minority persons but rather modest reductions for all racial/ethnic groups. Conclusions Although behavioral and technological interventions can result in some modest improvements in glycemic control, these interventions did not fare significantly better than usual care in achieving glycemic control. More

  20. Suppression of population transport and control of exciton distributions by entangled photons.

    PubMed

    Schlawin, Frank; Dorfman, Konstantin E; Fingerhut, Benjamin P; Mukamel, Shaul

    2013-01-01

    Entangled photons provide an important tool for secure quantum communication, computing and lithography. Low intensity requirements for multi-photon processes make them idealy suited for minimizing damage in imaging applications. Here we show how their unique temporal and spectral features may be used in nonlinear spectroscopy to reveal properties of multiexcitons in chromophore aggregates. Simulations demostrate that they provide unique control tools for two-exciton states in the bacterial reaction centre of Blastochloris viridis. Population transport in the intermediate single-exciton manifold may be suppressed by the absorption of photon pairs with short entanglement time, thus allowing the manipulation of the distribution of two-exciton states. The quantum nature of the light is essential for achieving this degree of control, which cannot be reproduced by stochastic or chirped light. Classical light is fundamentally limited by the frequency-time uncertainty, whereas entangled photons have independent temporal and spectral characteristics not subjected to this uncertainty.

  1. Entrainment and Control of Bacterial Populations: An in Silico Study over a Spatially Extended Agent Based Model.

    PubMed

    Mina, Petros; Tsaneva-Atanasova, Krasimira; Bernardo, Mario di

    2016-07-15

    We extend a spatially explicit agent based model (ABM) developed previously to investigate entrainment and control of the emergent behavior of a population of synchronized oscillating cells in a microfluidic chamber. Unlike most of the work in models of control of cellular systems which focus on temporal changes, we model individual cells with spatial dependencies which may contribute to certain behavioral responses. We use the model to investigate the response of both open loop and closed loop strategies, such as proportional control (P-control), proportional-integral control (PI-control) and proportional-integral-derivative control (PID-control), to heterogeinities and growth in the cell population, variations of the control parameters and spatial effects such as diffusion in the spatially explicit setting of a microfluidic chamber setup. We show that, as expected from the theory of phase locking in dynamical systems, open loop control can only entrain the cell population in a subset of forcing periods, with a wide variety of dynamical behaviors obtained outside these regions of entrainment. Closed-loop control is shown instead to guarantee entrainment in a much wider region of control parameter space although presenting limitations when the population size increases over a certain threshold. In silico tracking experiments are also performed to validate the ability of classical control approaches to achieve other reference behaviors such as a desired constant output or a linearly varying one. All simulations are carried out in BSim, an advanced agent-based simulator of microbial population which is here extended ad hoc to include the effects of control strategies acting onto the population. PMID:27110835

  2. Indoor tanning and risk of melanoma: a case-control study in a highly exposed population

    PubMed Central

    Lazovich, DeAnn; Vogel, Rachel Isaksson; Berwick, Marianne; Weinstock, Martin A.; Anderson, Kristin E.; Warshaw, Erin M.

    2010-01-01

    Background Indoor tanning has been only weakly associated with melanoma risk; most reports were unable to adjust for sun exposure, confirm a dose-response, or examine specific tanning devices. A population-based case-control study was conducted to address these limitations. Methods Cases of invasive cutaneous melanoma, diagnosed in Minnesota between 2004-2007 at ages 25-59, were ascertained from a statewide cancer registry; age-, gender-matched controls were randomly selected from state driver's license lists. Self-administered questionnaires and telephone interviews included information on ever use of indoor tanning, device types used, initiation age, period of use, dose, duration, and indoor-tanning related burns. Odds ratios (OR) and 95% confidence intervals (CI) were adjusted for known melanoma risk factors. Results Among 1167 cases and 1101 controls, 62.9% of cases and 51.1% of controls had tanned indoors (adjusted OR 1.74, 95% CI 1.42-2.14). Melanoma risk was pronounced among users of UVB-enhanced (adjusted OR 2.86, 95% CI 2.03-4.03) and primarily UVA-emitting devices (adjusted OR 4.44, 95% CI 2.45, 8.02). Risk increased with use: years (p<0.006), hours (p<0.0001), or sessions (p=0.0002). Odds ratios were elevated within each initiation age category; among indoor tanners, years used was more relevant for melanoma development. Conclusions In a highly exposed population, frequent indoor tanning increased melanoma risk, regardless of age when indoor tanning began. Elevated risks were observed across devices. Impact This study overcomes some of the limitations of earlier reports and provides strong support for the recent declaration by International Agency for Research on Cancer that tanning devices are carcinogenic in humans. PMID:20507845

  3. Free-roaming dog population estimation and status of the dog population management and rabies control program in Dhaka City, Bangladesh.

    PubMed

    Tenzin, Tenzin; Ahmed, Rubaiya; Debnath, Nitish C; Ahmed, Garba; Yamage, Mat

    2015-05-01

    Beginning January 2012, a humane method of dog population management using a Catch-Neuter-Vaccinate-Release (CNVR) program was implemented in Dhaka City, Bangladesh as part of the national rabies control program. To enable this program, the size and distribution of the free-roaming dog population needed to be estimated. We present the results of a dog population survey and a pilot assessment of the CNVR program coverage in Dhaka City. Free-roaming dog population surveys were undertaken in 18 wards of Dhaka City on consecutive days using mark-resight methods. Data was analyzed using Lincoln-Petersen index-Chapman correction methods. The CNVR program was assessed over the two years (2012-2013) whilst the coverage of the CNVR program was assessed by estimating the proportion of dogs that were ear-notched (processed dogs) via dog population surveys. The free-roaming dog population was estimated to be 1,242 (95 % CI: 1205-1278) in the 18 sampled wards and 18,585 dogs in Dhaka City (52 dogs/km2) with an estimated human-to-free-roaming dog ratio of 828:1. During the two year CNVR program, a total of 6,665 dogs (3,357 male and 3,308 female) were neutered and vaccinated against rabies in 29 of the 92 city wards. A pilot population survey indicated a mean CNVR coverage of 60.6% (range 19.2-79.3%) with only eight wards achieving > 70% coverage. Given that the coverage in many neighborhoods was below the WHO-recommended threshold level of 70% for rabies eradications and since the CNVR program takes considerable time to implement throughout the entire Dhaka City area, a mass dog vaccination program in the non-CNVR coverage area is recommended to create herd immunity. The findings from this study are expected to guide dog population management and the rabies control program in Dhaka City and elsewhere in Bangladesh.

  4. Occupational risk factors for brain cancer: a population-based case-control study in Iowa.

    PubMed

    Zheng, T; Cantor, K P; Zhang, Y; Keim, S; Lynch, C F

    2001-04-01

    A number of occupations and industries have been inconsistently associated with the risk of brain cancer. To further explore possible relationships, we conducted a population-based case-control study of brain glioma in the state of Iowa, involving 375 histologically confirmed incident cases and 2434 population-based controls. Among men, the industries and/or occupations that had a significantly increased risk for employment of more than 10 years included roofing, siding, and sheet metalworking; newspaper work; rubber and plastics products, particularly tires and inner tubes; miscellaneous manufacturing industries; wholesale trade of durable goods, grain, and field beans; cleaning and building service occupations; miscellaneous mechanics and repairers; and janitors and cleaners. Subjects who worked in plumbing, heating, and air conditioning; electrical services; gasoline service stations; and military occupations also experienced a significantly increased risk. Among women, significant excess risk was observed for occupations in agricultural services and farming, apparel and textile products, electrical and electronic equipment manufacturing, various retail sales, record-keeping, and restaurant service. Workers in industries with a potential for gasoline or motor exhaust exposures experienced a non-significant excess risk of brain glioma.

  5. Guidelines to site selection for population surveillance and mosquito control trials: a case study from Mauritius.

    PubMed

    Iyaloo, Diana P; Elahee, Khouaildi B; Bheecarry, Ambicadutt; Lees, Rosemary Susan

    2014-04-01

    Many novel approaches to controlling mosquito vectors through the release of sterile and mass reared males are being developed in the face of increasing insecticide resistance and other limitations of current methods. Before full scale release programmes can be undertaken there is a need for surveillance of the target population, and investigation of parameters such as dispersal and longevity of released, as compared to wild males through mark-release-recapture (MRR) and other experiments, before small scale pilot trials can be conducted. The nature of the sites used for this field work is crucial to ensure that a trial can feasibly collect sufficient and relevant information, given the available resources and practical limitations, and having secured the correct regulatory, community and ethical approvals and support. Mauritius is considering the inclusion of the sterile insect technique (SIT), for population reduction of Aedes albopictus, as a component of the Ministry of Health and Quality of Life's 'Operational Plan for Prevention and Control of Chikungunya and Dengue'. As part of an investigation into the feasibility of integrating the SIT into the Integrated Vector Management (IVM) scheme in Mauritius a pilot trial is planned. Two potential sites have been selected for this purpose, Pointe des Lascars and Panchvati, villages in the North East of the country, and population surveillance has commenced. This case study will here be used to explore the considerations which go into determining the most appropriate sites for mosquito field research. Although each situation is unique, and an ideal site may not be available, this discussion aims to help researchers to consider and balance the important factors and select field sites that will meet their needs.

  6. Inhibition control and working memory capacity in children with SLI

    PubMed Central

    Marton, Klara; Kelmenson, Lyudmyla; Pinkhasova, Milana

    2007-01-01

    This study examined the “inefficient inhibition hypothesis” (IIH; Bjorklund & Harnishfeger, 1990; Wilson & Kipp, 1998) in three groups: children with specific language impairment (SLI), age-matched and language-matched controls. The IIH suggests that individuals with efficient inhibition skills perform better on working memory tasks because they are able to keep out irrelevant information from working memory. Children with SLI show processing capacity limitations. This study examined whether the working memory limitations are impacted by inhibition problems in this population. Working memory capacity was measured with a listening span task and children’s inhibition errors were categorized. These errors reflected either immediate or delayed inhibition problems and they indicated either contextual distractions or perseverations. Children with SLI produced more inhibition errors than their peers in most categories. The results show an association between inhibition control and working memory capacity, but the direction of causality is not clear. PMID:18545677

  7. A Survey to Identify University Student Attitudes toward the Role of Government in Controlling Human Population Growth.

    ERIC Educational Resources Information Center

    Yost, Thomas E.

    The purpose of this study was to obtain, measure, and evaluate the attitudes of postsecondary students on domestic population issues in order to determine the extent of support for a national government-controlled population stabilization program. A total of 125 students enrolled in either the American government or general sociology course at the…

  8. Caesarean Delivery and Postpartum Maternal Mortality: A Population-Based Case Control Study in Brazil

    PubMed Central

    Esteves-Pereira, Ana Paula; Deneux-Tharaux, Catherine; Nakamura-Pereira, Marcos; Saucedo, Monica; Bouvier-Colle, Marie-Hélène; Leal, Maria do Carmo

    2016-01-01

    Background Cesarean delivery rates continue to increase worldwide and reached 57% in Brazil in 2014. Although the safety of this surgery has improved in the last decades, this trend is a concern because it carries potential risks to women’s health and may be a modifiable risk factor of maternal mortality. This paper aims to investigate the risk of postpartum maternal death directly associated with cesarean delivery in comparison to vaginal delivery in Brazil. Methods This was a population-based case—control study performed in eight Brazilian states. To control for indication bias, deaths due to antenatal morbidity were excluded. We included 73 cases of postpartum maternal deaths from 2009–2012. Controls were selected from the Birth in Brazil Study, a 2011 nationwide survey including 9,221 postpartum women. We examined the association of cesarean section and postpartum maternal death by multivariate logistic regression, adjusting for confounders. Results After controlling for indication bias and confounders, the risk of postpartum maternal death was almost three-fold higher with cesarean than vaginal delivery (OR 2.87, 95% CI 1.63–5.06), mainly due to deaths from postpartum hemorrhage and complications of anesthesia. Conclusion Cesarean delivery is an independent risk factor of postpartum maternal death. Clinicians and patients should consider this fact in balancing the benefits and risks of the procedure. PMID:27073870

  9. Serum trace element differences between Schizophrenia patients and controls in the Han Chinese population

    PubMed Central

    Cai, Lei; Chen, Tianlu; Yang, Jinglei; Zhou, Kejun; Yan, Xiaomei; Chen, Wenzhong; Sun, Liya; Li, Linlin; Qin, Shengying; Wang, Peng; Yang, Ping; Cui, Donghong; Burmeister, Margit; He, Lin; Jia, Wei; Wan, Chunling

    2015-01-01

    Little is known about the trace element profile differences between Schizophrenia patients and healthy controls; previous studies about the association of certain elements with Schizophrenia have obtained conflicting results. To identify these differences in the Han Chinese population, inductively coupled plasma-mass spectrometry was used to quantify the levels of 35 elements in the sera of 111 Schizophrenia patients and 110 healthy participants, which consisted of a training (61/61 for cases/controls included) and a test group including remaining participants. An orthogonal projection to latent structures model was constructed from the training group (R2Y = 0.465, Q2cum = 0.343) had a sensitivity of 76.0% and a specificity of 71.4% in the test group. Single element analysis indicated that the concentrations of cesium, zinc, and selenium were significantly reduced in patients with Schizophrenia in both the training and test groups. The meta-analysis including 522 cases and 360 controls supported that Zinc was significantly associated with Schizophrenia (standardized mean difference [SMD], −0.81; 95% confidence intervals [CI], −1.46 to −0.16, P = 0.01) in the random-effect model. Information theory analysis indicated that Zinc could play roles independently in Schizophrenia. These results suggest clear element profile differences between patients with Schizophrenia and healthy controls, and reduced Zn level is confirmed in the Schizophrenia patients. PMID:26456296

  10. Multidimensional morphometric 3D MRI analyses for detecting brain abnormalities in children: impact of control population.

    PubMed

    Wilke, Marko; Rose, Douglas F; Holland, Scott K; Leach, James L

    2014-07-01

    Automated morphometric approaches are used to detect epileptogenic structural abnormalities in 3D MR images in adults, using the variance of a control population to obtain z-score maps in an individual patient. Due to the substantial changes the developing human brain undergoes, performing such analyses in children is challenging. This study investigated six features derived from high-resolution T1 datasets in four groups: normal children (1.5T or 3T data), normal clinical scans (3T data), and patients with structural brain lesions (3T data), with each n = 10. Normative control data were obtained from the NIH study on normal brain development (n = 401). We show that control group size substantially influences the captured variance, directly impacting the patient's z-scores. Interestingly, matching on gender does not seem to be beneficial, which was unexpected. Using data obtained at higher field scanners produces slightly different base rates of suprathreshold voxels, as does using clinically derived normal studies, suggesting a subtle but systematic effect of both factors. Two approaches for controlling suprathreshold voxels in a multidimensional approach (combining features and requiring a minimum cluster size) were shown to be substantial and effective in reducing this number. Finally, specific strengths and limitations of such an approach could be demonstrated in individual cases. PMID:25050423

  11. Lack of association between Toxoplasma gondii infection and hypertensive disorders in pregnancy: a case–control study in a Northern Mexican population

    PubMed Central

    2014-01-01

    Background The outcome of pregnancy is often threatened by hypertension disorders, i.e. eclampsia. Rate of infection with the protozoan parasite Toxoplasma gondii can be as high as 80% in pregnant women, and infection acquired during pregnancy can lead to fetal death. Very little is known about a potential association between infections, i.e. those with Toxoplasma gondii, and hypertensive disorders during pregnancy. Methods Through a case–control study design, we investigated the presence of anti-Toxoplasma IgG and anti-Toxoplasma IgM antibodies in 146 pregnant women suffering from hypertensive disorders (cases) and 146 age-matched normotensive pregnant women (controls) attending a public hospital in Durango City, Mexico. Obstetric and blood pressure characteristics from cases and controls were also obtained. Results Seroprevalence of anti-Toxoplasma IgG antibodies and IgG titers did not differ significantly in controls (8/146; 5.5%) and cases (9/146; 6.2%). Anti-Toxoplasma IgM antibodies were found in 2 (1.2%) controls and none of the cases. Seroprevalence of T. gondii in controls (5.5%) was similar to seroprevalences found in patients with mild preeclampsia (4/27: 14.8%), severe preeclampsia (5/95: 5.3%), eclampsia (0/16: 0%) and HELLP syndrome (hemolysis, elevated liver enzymes, and low platelet count) (0/8: 0%) (P = 0.23). Conclusions Our results suggest that latent infection with T. gondii is not associated with hypertensive disorders in pregnant women in Northern Mexico. Further studies with larger sample sizes are needed to elucidate the association of infection with T. gondii with hypertensive disorders in pregnancy. PMID:24708729

  12. Incidence and risk of chondrolysis in Denmark: A nationwide population-based study

    PubMed Central

    Christiansen, Christian F; Thygesen, Sandra K; Pedersen, Lars

    2010-01-01

    Background: Chondrolysis is a rare disease with destruction of cartilage of joints. Incidence and risk factors have not been studied in a formal epidemiologic population-based setting. Methods: We used the Danish National Registry of Patients (NRP) covering all Danish hospitals to identify all cases of chondrolysis from 1994 to 2008. Incidence rates were estimated using the general population as the denominator. For each chondrolysis patient, 10 age-matched population controls were sampled for a case-control analysis. For cases and controls, we ascertained in the NRP history of diabetes, rheumatoid arthritis, orthopedic surgery, including surgery of shoulder and upper arm, injury to shoulder girdle or upper arm, and treatment with pain pump. We determined the prevalence of these risk factors in cases and controls, and computed odds ratios (OR). Results: We identified 43 patients with chondrolysis in the 15-year study period. The incidence rate was 5.5 per 10,000,000 person-years. Diabetes was more prevalent in chondrolysis cases, compared with the 430 controls (OR = 6.7; 95% confidence intervals [CI]: 1.1–39.9). Orthopedic surgery was also associated with an increased risk of chondrolysis (OR = 28.8, 95% CI: 11.0–75.6), while previous injury was not (OR = 0.8; 95% CI: 0.1–5.9). Conclusion: Chondrolysis was rarely diagnosed in Denmark. Diabetes and orthopedic surgery may be risk factors. PMID:20865107

  13. Impact of the Massachusetts tobacco control programme: population based trend analysis

    PubMed Central

    Biener, Lois; Harris, Jeffrey E; Hamilton, William

    2000-01-01

    Objective To assess the impact of the Massachusetts tobacco control programme, which, since its start in January 1993, has spent over $200m—“the highest per capita expenditure for tobacco control in the world”—funded by an extra tax of 25 cents per pack of cigarettes. Design Population based trend analysis with comparison group. Subjects Adult residents of Massachusetts and other US states excluding California. Main outcome measures Per capita consumption of cigarettes as measured by states' sales tax records; prevalence of smoking in adults as measured by several population-based telephone surveys. Results From 1988 to 1992, decline in per capita consumption of cigarettes in Massachusetts (15%) was similar to that in the comparison states (14%), corresponding to an annual decline of 3-4% for both groups. During 1992-3, consumption continued to decline by 4% in the comparison states but dropped 12% in Massachusetts in response to the tax increase. From 1993 onward, consumption in Massachusetts showed a consistent annual decline of more than 4%, whereas in the comparison states it levelled off, decreasing by less than 1% a year. From 1992, the prevalence of adult smoking in Massachusetts has declined annually by 0.43% (95% confidence interval 0.21% to 0.66%) compared with an increase of 0.03% (-0.06% to 0.12%) in the comparison states (P<0.001). Conclusions These findings show that a strongly implemented, comprehensive tobacco control programme can significantly reduce tobacco use. PMID:10926595

  14. Fetal Growth and Risk of Stillbirth: A Population-Based Case–Control Study

    PubMed Central

    Bukowski, Radek; Hansen, Nellie I.; Willinger, Marian; Reddy, Uma M.; Parker, Corette B.; Pinar, Halit; Silver, Robert M.; Dudley, Donald J.; Stoll, Barbara J.; Saade, George R.; Koch, Matthew A.; Rowland Hogue, Carol J.; Varner, Michael W.; Conway, Deborah L.; Coustan, Donald; Goldenberg, Robert L.

    2014-01-01

    Background Stillbirth is strongly related to impaired fetal growth. However, the relationship between fetal growth and stillbirth is difficult to determine because of uncertainty in the timing of death and confounding characteristics affecting normal fetal growth. Methods and Findings We conducted a population-based case–control study of all stillbirths and a representative sample of live births in 59 hospitals in five geographic areas in the US. Fetal growth abnormalities were categorized as small for gestational age (SGA) (<10th percentile) or large for gestational age (LGA) (>90th percentile) at death (stillbirth) or delivery (live birth) using population, ultrasound, and individualized norms. Gestational age at death was determined using an algorithm that considered the time-of-death interval, postmortem examination, and reliability of the gestational age estimate. Data were weighted to account for the sampling design and differential participation rates in various subgroups. Among 527 singleton stillbirths and 1,821 singleton live births studied, stillbirth was associated with SGA based on population, ultrasound, and individualized norms (odds ratio [OR] [95% CI]: 3.0 [2.2 to 4.0]; 4.7 [3.7 to 5.9]; 4.6 [3.6 to 5.9], respectively). LGA was also associated with increased risk of stillbirth using ultrasound and individualized norms (OR [95% CI]: 3.5 [2.4 to 5.0]; 2.3 [1.7 to 3.1], respectively), but not population norms (OR [95% CI]: 0.6 [0.4 to 1.0]). The associations were stronger with more severe SGA and LGA (<5th and >95th percentile). Analyses adjusted for stillbirth risk factors, subset analyses excluding potential confounders, and analyses in preterm and term pregnancies showed similar patterns of association. In this study 70% of cases and 63% of controls agreed to participate. Analysis weights accounted for differences between consenting and non-consenting women. Some of the characteristics used for individualized fetal growth estimates were missing

  15. Context by treatment interactions as the primary object of study in cluster randomized controlled trials of population health interventions.

    PubMed

    Fuller, Daniel; Potvin, Louise

    2012-06-01

    Cluster randomized controlled trials are increasingly used in population health intervention research. Through randomization, researchers attempt to isolate the treatment effect and remove all other effects, including any effects of social context. In many cases, the constant effect assumption cannot be satisfied in cluster randomized controlled trials. We argue that when studying population health interventions, the effective mechanism of intervention lies in the interaction between the treatment and social context. Researchers should be cognizant that attempts to remove the effect of social context using CRTC may fail. The interaction between the treatment and social context should be the primary object of study in population health intervention research.

  16. Coherent Control of Population Transfer via Linear Chirp in Liquid Solution: The Role of Motional Narrowing.

    PubMed

    McRobbie, Porscha L; Geva, Eitan

    2016-05-19

    The conditions under which linear chirp can be used to control population transfer between the electronic states of a chromophore dissolved in liquid solution are investigated. To this end, we model the chromophore as a two-state system with shifted electronic potential energy surfaces and a fluctuating electronic transition frequency. The fluctuations are described as an exponentially correlated Gaussian stochastic process, which can be characterized by the average fluctuation amplitude, σ, and correlation time, τc. The time-dependent Schrödinger equation is solved numerically for an ensemble of stochastic histories, at different values of σ and τc, and under a wide range of pulse intensities and linear chirp coefficients. In the limit τc → ∞, we find that control diminishes rapidly as soon as σ exceeds the bandwidth of the pulse. However, we also find that control can be regained by reducing τc. We attribute this trend to motional narrowing, whereby decreasing τc narrows down the effective bandwidth of the solvent-induced fluctuations. The results suggest that the choice of methanol as a solvent in the actual experimental demonstration of chirp control by Cerullo et al. [ Chem. Phys. Lett. 1996 , 262 , 362 - 368 ] may have contributed to its success, due to the particularly short τc (∼20 fs) that the rapid librations of this hydrogen bonded liquid give rise to. The results also give rise to the rather surprising prediction that coherent control in liquid solution can be strongly dependent on the choice of solvent and be improved upon by choosing solvents that correspond to lower values of στc.

  17. TickBot: a novel robotic device for controlling tick populations in the natural environment.

    PubMed

    Gaff, Holly D; White, Alexis; Leas, Kyle; Kelman, Pamela; Squire, James C; Livingston, David L; Sullivan, Gerald A; Baker, Elizabeth W; Sonenshine, Daniel E

    2015-03-01

    A semi-autonomous 4-wheeled robot (TickBot) was fitted with a denim cloth treated with an acaricide (permethrin™) and tested for its ability to control ticks in a tick-infested natural environment in Portsmouth, Virginia. The robot's sensors detect a magnetic field signal from a guide wire encased in 80m polyethylene tubing, enabling the robot to follow the trails, open areas and other terrain where the tubing was located. To attract ticks to the treated area, CO2 was distributed through the same tubing, fitted with evenly spaced pores and flow control valves, which permitted uniform CO2 distribution. Tests were done to determine the optimum frequency for TickBot to traverse the wire-guided treatment site as well as the duration of operation that could be accomplished on a single battery charge. Prior to treatment, dragging was done to determine the natural abundance of ticks in the test site. Controls were done without CO2 and without permethrin. TickBot proved highly effective in reducing the overall tick densities to nearly zero with the treatment that included both carbon dioxide pretreatment and the permethrin treated cloth. Following a 60min traverse of the treatment areas, adult tick numbers, almost entirely Amblyomma americanum, was reduced to zero within 1h and remained at or near zero for 24h. Treatments without CO2 also showed reduction of ticks to near zero within 1h, but the populations were no different than the control sections at 4h. This study demonstrates the efficacy of TickBot as a tick control device to significantly reduce the risk of tick bites and disease transmission to humans and companion animals visiting a previously tick-infested natural environment. Continued deployment of TickBot for additional days or weeks can assure a relatively tick-safe environment for enjoyment by the public. PMID:25499615

  18. Aspirin Use Associated With Amyotrophic Lateral Sclerosis: a Total Population-Based Case-Control Study

    PubMed Central

    Tsai, Ching-Piao; Lin, Feng-Cheng; Lee, Johnny Kuang-Wu; Lee, Charles Tzu-Chi

    2015-01-01

    Background The association of aspirin use and nonsteroid anti-inflammatory drug (NSAID) use with amyotrophic lateral sclerosis (ALS) risk is unclear. This study determined whether use of any individual compound is associated with ALS risk by conducting a total population-based case-control study in Taiwan. Methods A total of 729 patients with newly diagnosed ALS who had a severely disabling disease certificate between January 1, 2002, and December 1, 2008, comprised the case group. These cases were compared with 7290 sex-, age-, residence-, and insurance premium-matched controls. Drug use by each Anatomical Therapeutic Chemical code was analyzed using conditional logistic regression models. False discovery rate (FDR)-adjusted P values were reported in order to avoid inflating false positives. Results Of the 1336 compounds, only the 266 with use cases exceeding 30 in our database were included in the screening analysis. Without controlling for steroid use, the analysis failed to reveal any compound that was inversely associated with ALS risk according to FDR criteria. After controlling for steroid use, we found use of the following compounds to be associated with ALS risk: aspirin, diphenhydramine (one of the antihistamines), and mefenamic acid (one of the NSAIDs). A multivariate analysis revealed that aspirin was independently inversely associated with ALS risk after controlling for diphenhydramine, mefenamic acid, and steroid use. The inverse association between aspirin and ALS was present predominately in patients older than 55 years. Conclusions The results of this study suggested that aspirin use might reduce the risk of ALS, and the benefit might be more prominent for older people. PMID:25721071

  19. Physical activity and subarachnoid haemorrhage: a population based case-control study

    PubMed Central

    Fann, J; Kukull, W; Katon, W; Longstreth, W

    2000-01-01

    OBJECTIVE—To evaluate physical activity as a risk factor for subarachnoid haemorrhage.
METHODS—A population based case-control study in King County, Washington. A standardised, personal interview was used to determine physical activity during the past year and at the onset of the bleed for case patients and a similar reference time for control subjects. Conditional logistic regression and a case cross over analysis were performed in which each case patient served as his or her own control. Subjects were 149 men and women with incident, spontaneous subarachnoid haemorrhage and two control subjects per case patient. Control subjects were identified through random digit dialing and matched on age, sex, and respondent type.
RESULTS—Four of the 149 (2.7%) case patients were engaged in vigorous physical activity at the time of their subarachnoid haemorrhage. With those who were engaged in non-vigorous or no physical activity serving as the reference group, the relative risk of sustaining a subarachnoid haemorrhage for those engaged in vigorous physical activity was 11.6 (95% confidence interval (95% CI) 1.2-113.2). In the case cross over analysis, the relative risk was 15.0 (95% CI 4.3-52.2). Higher levels of long term regular physical activity over the past year were associated with a lower, but not statistically significant, risk of subarachnoid haemorrhage (test for trend, p=0.3).
CONCLUSION—The risk of subarachnoid haemorrhage is increased during vigorous physical activity, although only a few result from this mechanism.

 PMID:11080229

  20. Cellular population dynamics control the robustness of the stem cell niche

    PubMed Central

    MacLean, Adam L.; Kirk, Paul D. W.; Stumpf, Michael P. H.

    2015-01-01

    ABSTRACT Within populations of cells, fate decisions are controlled by an indeterminate combination of cell-intrinsic and cell-extrinsic factors. In the case of stem cells, the stem cell niche is believed to maintain ‘stemness’ through communication and interactions between the stem cells and one or more other cell-types that contribute to the niche conditions. To investigate the robustness of cell fate decisions in the stem cell hierarchy and the role that the niche plays, we introduce simple mathematical models of stem and progenitor cells, their progeny and their interplay in the niche. These models capture the fundamental processes of proliferation and differentiation and allow us to consider alternative possibilities regarding how niche-mediated signalling feedback regulates the niche dynamics. Generalised stability analysis of these stem cell niche systems enables us to describe the stability properties of each model. We find that although the number of feasible states depends on the model, their probabilities of stability in general do not: stem cell–niche models are stable across a wide range of parameters. We demonstrate that niche-mediated feedback increases the number of stable steady states, and show how distinct cell states have distinct branching characteristics. The ecological feedback and interactions mediated by the stem cell niche thus lend (surprisingly) high levels of robustness to the stem and progenitor cell population dynamics. Furthermore, cell–cell interactions are sufficient for populations of stem cells and their progeny to achieve stability and maintain homeostasis. We show that the robustness of the niche – and hence of the stem cell pool in the niche – depends only weakly, if at all, on the complexity of the niche make-up: simple as well as complicated niche systems are capable of supporting robust and stable stem cell dynamics. PMID:26453624

  1. Natural enemies act faster than endophytic fungi in population control of cereal aphids.

    PubMed

    Härri, Simone A; Krauss, Jochen; Müller, Christine B

    2008-05-01

    1. Fast-growing populations of phytophagous insects can be limited by the presence of natural enemies and by alkaloids that are produced by symbiotic associations of many temperate grass species with endophytic fungi. It is unclear if and how acquired plant defences derived from endophytic fungi interact with natural enemies to affect phytophagous insect populations. 2. To assess the relative importance of endophytic fungi compared to that of natural enemies on the population dynamics of phytophagous insects, we carried out a fully factorial field experiment, in which the presence of natural enemies and the presence of endophytic fungi were manipulated simultaneously. Target colonies of aphids were monitored for 8 weeks starting from their natural appearance in the field to the end of the aphid season. 3. We show that on Lolium perenne increased natural enemy densities reduced the individual numbers of two common cereal aphids, Rhopalosiphum padi and Metopolophium festucae. 4. The presence of the endophytic fungi Neotyphodium lolii reduced the number of M. festucae but did not affect the number of R. padi. The reduction in R. padi numbers by predators and parasitoids was not influenced by the presence of endophytes. For adult M. festucae, however, the negative effects of natural enemies were significant only in the absence of endophytes. 5. Over the duration of the experiment, the effect of natural enemies on aphid colony growth was much stronger than the effect of the endophytic fungi N. lolii, presumably because predator and parasitoid action on aphid colonies is much faster than any effects of endophytes. 6. Our results demonstrate that with simultaneous action of acquired endosymbionts and natural enemies, both factors can control aphid colony growth but they generally act independently of each other.

  2. Is wide availability of abortion essential to national population growth control programs? Experiences of 116 countries.

    PubMed

    Mumford, S D; Kessel, E

    1984-07-15

    No nation wanting to reduce its growth rate to less than or equal to 1% can expect to do so without the widespread use of abortion. This study, based on the experience of 116 of the world's largest countries, supports the contention that abortion is essential to any national population growth control effort. Existing circumstances in developed countries have facilitated reduction of growth rates to less than 1%, with abortion rates generally in the range of 200 to 500 per 1000 live births. However, developing countries are faced with a different and more difficult set of circumstances that require even greater reliance on abortion. These obstacles include a young population with resultant rapidly growing numbers of young fertile women, poor contraceptive use-effectiveness, low prevalence of contraception, and poor or nonexistent systems for providing contraceptives. By virtue of their profession, physicians play a critical role in family planning and carry a special responsibility in ensuring that abortion services are available to all women who need them.

  3. Artificially Constructed Quorum-Sensing Circuits Are Used for Subtle Control of Bacterial Population Density

    PubMed Central

    Wang, Zhaoshou; Wu, Xin; Peng, Jianghai; Hu, Yidan; Fang, Baishan; Huang, Shiyang

    2014-01-01

    Vibrio fischeri is a typical quorum-sensing bacterium for which lux box, luxR, and luxI have been identified as the key elements involved in quorum sensing. To decode the quorum-sensing mechanism, an artificially constructed cell–cell communication system has been built. In brief, the system expresses several programmed cell-death BioBricks and quorum-sensing genes driven by the promoters lux pR and PlacO-1 in Escherichia coli cells. Their transformation and expression was confirmed by gel electrophoresis and sequencing. To evaluate its performance, viable cell numbers at various time periods were investigated. Our results showed that bacteria expressing killer proteins corresponding to ribosome binding site efficiency of 0.07, 0.3, 0.6, or 1.0 successfully sensed each other in a population-dependent manner and communicated with each other to subtly control their population density. This was also validated using a proposed simple mathematical model. PMID:25119347

  4. Evidence that sea lamprey control led to recovery of the burbot population in Lake Erie

    USGS Publications Warehouse

    Stapanian, M.A.; Madenjian, C.P.; Witzel, L.D.

    2006-01-01

    Between 1987 and 2003, the abundance of burbot Lota lota in eastern Lake Erie increased significantly, especially in Ontario waters. We considered four hypotheses to explain this increase: (1) reduced competition with lake trout Salvelinus namaycush, the other major coldwater piscivore in Lake Erie; (2) increased abundance of the two main prey species, rainbow smelt Osmerus mordax and round goby Neogobius melanostomus; (3) reduced interference with burbot reproduction by alewives Alosa pseudoharengus; and (4) reduced predation by sea lampreys Petromyzon marinus on burbot. Species abundance data did not support the first three hypotheses. Our results suggested that the apparent recovery of the burbot population of Lake Erie was driven by effective sea lamprey control. Sea lamprey predation appeared to be the common factor affecting burbot abundance in Lakes Michigan, Huron, Erie, and Ontario. In addition, relatively high alewife density probably depressed burbot abundance in Lakes Ontario and Michigan. We propose that a healthy adult lake trout population may augment burbot recovery in some lakes by serving as a buffer against sea lamprey predation and will not negatively impact burbot through competition.

  5. Quantifying penetrance in a dominant disease gene using large population control cohorts

    PubMed Central

    Minikel, Eric Vallabh; Vallabh, Sonia M.; Lek, Monkol; Estrada, Karol; Samocha, Kaitlin E.; Sathirapongsasuti, J. Fah; McLean, Cory Y.; Tung, Joyce Y.; Yu, Linda P.C.; Gambetti, Pierluigi; Blevins, Janis; Zhang, Shulin; Cohen, Yvonne; Chen, Wei; Yamada, Masahito; Hamaguchi, Tsuyoshi; Sanjo, Nobuo; Mizusawa, Hidehiro; Nakamura, Yosikazu; Kitamoto, Tetsuyuki; Collins, Steven J.; Boyd, Alison; Will, Robert G.; Knight, Richard; Ponto, Claudia; Zerr, Inga; Kraus, Theo F.J.; Eigenbrod, Sabina; Giese, Armin; Calero, Miguel; de Pedro-Cuesta, Jesús; Haïk, Stéphane; Laplanche, Jean-Louis; Bouaziz-Amar, Elodie; Brandel, Jean-Philippe; Capellari, Sabina; Parchi, Piero; Poleggi, Anna; Ladogana, Anna; O'Donnell-Luria, Anne H.; Karczewski, Konrad J.; Marshall, Jamie L.; Boehnke, Michael; Laakso, Markku; Mohlke, Karen L.; Kähler, Anna; Chambert, Kimberly; McCarroll, Steven; Sullivan, Patrick F.; Hultman, Christina M.; Purcell, Shaun M.; Sklar, Pamela; van der Lee, Sven J.; Rozemuller, Annemieke; Jansen, Casper; Hofman, Albert; Kraaij, Robert; van Rooij, Jeroen G.J.; Ikram, M. Arfan; Uitterlinden, André G.; van Duijn, Cornelia M.; Daly, Mark J.; MacArthur, Daniel G.

    2016-01-01

    More than 100,000 genetic variants are reported to cause Mendelian disease in humans, but the penetrance - the probability that a carrier of the purported disease-causing genotype will indeed develop the disease - is generally unknown. Here we assess the impact of variants in the prion protein gene (PRNP) on the risk of prion disease by analyzing 16,025 prion disease cases, 60,706 population control exomes, and 531,575 individuals genotyped by 23andMe, Inc. We show that missense variants in PRNP previously reported to be pathogenic are at least 30× more common in the population than expected based on genetic prion disease prevalence. While some of this excess can be attributed to benign variants falsely assigned as pathogenic, other variants have genuine effects on disease susceptibility but confer lifetime risks ranging from <0.1% to ~100%. We also show that truncating variants in PRNP have position-dependent effects, with true loss-of-function alleles found in healthy older individuals, supporting the safety of therapeutic suppression of prion protein expression. PMID:26791950

  6. Electroencephalographic coherence in Alzheimer's disease: comparisons with a control group and population norms.

    PubMed

    Knott, V; Mohr, E; Mahoney, C; Ilivitsky, V

    2000-01-01

    Previous research from independent laboratories has shown reduced electroencephalographic coherence in patients diagnosed with dementia of the Alzheimer type (DAT). This study added to this work by comparing interhemispheric and intrahemispheric coherence in nonmedicated DAT patients (n = 35) with that of a normal control group (n = 30), as well as with a data bank of population norms. Raw and Z-score transformed values showed reduced coherence, interhemispherically (in delta, theta, alpha, and beta bands) and intrahemispherically (delta and theta bands) in DAT patients with both comparison procedures. Discriminant analysis correctly classified 73% to 75% of patients. The results are discussed in relation to earlier research, "trait" versus "state" factors, the cholinergic system, and cognitive processes in dementia.

  7. Factors controlling the summer development of copepod populations in the southern bight of the North Sea

    NASA Astrophysics Data System (ADS)

    Daan, Rogier

    In two consecutive years an intensive sampling programmed was implemented at a fixed station in Dutch coastal waters to obtain a detailed record of the summer development of copepod populations in relation to phytoplankton and macroplankton abundance. The central question was whether densities of copepods are controlled by predation, in particular by invertebrate pelagic carnivores, or by food limitation. Methods applied to estimate daily predation by observed stocks of carnivores included analysis of gut contents and digestion rate, extrapolation of experimental feeding rates and of literature data on daily rations and maintenance needs. Chlorophyll- a and cell concentrations served as a rough measure for algal food supply. Since a decline in copepod densities manifested itself most clearly in decreasing naupliar numbers in both years, populations were assumed to be regulated mainly by recruitment or survival of these early life stages. Naupliar declines coincided with maximum densities of the hydromedusa Phialidium hemisphaericum, which dominated the macroplankton both in abundance and in biomass and reached a maximum density of 467 specimens·m -3 or 7 mg C·m -3. Copepod eggs appeared by far the most frequent prey item in their guts. However, these eggs are digested very slowly, if at all, and may often be ejected without any visible damage. The effect of egg predation on naupliar recruitment seems therefore relatively unimportant. Predation on swimming copepod stages was generally low. There was no evidence of selective feeding on nauplii. The maximum values of calculated predation pressure exerted by Phialidium populations matched daily copepod production only by way of exception. Impact of other invertebrate carnivores was negligible. As predation did not play a significant role, food availability seems the key factor underlying copepod population dynamics. The consequences of food limitation (reduced egg production, production of diapause eggs and enhanced

  8. Population-based, Case-Control-Family Design to Investigate Genetic and Environmental Influences on Melanoma Risk

    PubMed Central

    Cust, Anne E.; Schmid, Helen; Maskiell, Judith A.; Jetann, Jodie; Ferguson, Megan; Holland, Elizabeth A.; Agha-Hamilton, Chantelle; Jenkins, Mark A.; Kelly, John; Kefford, Richard F.; Giles, Graham G.; Armstrong, Bruce K.; Aitken, Joanne F.; Hopper, John L.; Mann, Graham J.

    2009-01-01

    Discovering and understanding genetic risk factors for melanoma and their interactions with phenotype, sun exposure, and other risk factors could lead to new strategies for melanoma control. This paper describes the Australian Melanoma Family Study, which uses a multicenter, population-based, case-control-family design. From 2001 to 2005, the authors recruited 1,164 probands including 629 cases with histopathologically confirmed, first-primary cutaneous melanoma diagnosed before age 40 years, 240 population-based controls frequency matched for age, and 295 spouse/friend controls. Information on lifetime sun exposure, phenotype, and residence history was collected for probands and nearly 4,000 living relatives. More than 3,000 subjects donated a blood sample. Proxy-reported information was collected for childhood sun exposure and deceased relatives. Important features of this study include the population-based, family-based design; a focus on early onset disease; probands from 3 major cities differing substantially in solar ultraviolet exposure and melanoma incidence; a population at high risk because of high ultraviolet exposure and susceptible pigmentation phenotypes; population-based, spouse/friend, and sibling controls; systematic recruitment of relatives of case and control probands; self and parent reports of childhood sun exposure; and objective clinical skin examinations. The authors discuss methodological and analytical issues related to the study design and conduct, as well as the potentially novel insights the study can deliver. PMID:19887461

  9. Alcohol Habits in Patients with Long-Term Musculoskeletal Pain: Comparison with a Matched Control Group from the General Population

    ERIC Educational Resources Information Center

    Thelin Bronner, Kerstin Birgitta; Wennberg, Peter; Kallmen, Hakan; Schult, Marie-Louise Birgitta

    2012-01-01

    This prospective study aimed to describe alcohol habits in patients with chronic pain compared with those in a matched control group from the general Swedish population. In total, 100 consecutive patients enrolled were matched against 100 individuals in a control group on the basis of age and sex. Alcohol habits were measured using the Alcohol Use…

  10. Optimal birth control of population dynamics. II. Problems with free final time, phase constraints, and mini-max costs.

    PubMed

    Chan, W L; Guo, B Z

    1990-03-01

    A previous analysis of optimal birth control of population systems of the McKendrick type (a distributed parameter system involving 1st order partial differential equations with nonlocal bilinear boundary control) raised 3 additional issues--free final time problem, system with phase constraints, and the mini-max control problem of a population. The free final time problem considers the minimum time problem to be a special case, but relaxes many convexity assumptions. Theorems (maximum principles) and corollaries are developed that flow from the terminology and mathematical notations set forth in the earlier article.

  11. Prevalence, awareness, treatment and control of high blood pressure among Chinese rural population in Haimen, Jiangsu.

    PubMed

    Li, T; Xian, Y; Mao, H-M; Jiang, W-J; Zhang, L; Chow, E P F; Huang, J-P; Lu, Y-H; Tian, T; Jiang, S-Y; Zhuang, X

    2016-04-01

    Nowadays, high blood pressure (HBP) is one of the most common chronic diseases in China. This survey aims to assess HBP prevalence, and related disease awareness, treatment and control among rural population in Haimen, Jiangsu province, China. A total of 7538 rural residents, aged over 18 years, from four randomly selected villages in Haimen, were selected to participate in the blood pressure examination in September 2010, the male-to-female ratio of participants was 1:1.57. In all, 2034 patients were diagnosed with HBP. The total crude prevalence of HBP was 26.98%, the overall standardized prevalence of HBP was 24.38%. Both male and female prevalence rates demonstrate ascending trend with age. Awareness, treatment and control rates among all patients were 68.34%, 61.46% and 27.43% respectively, whereas the corresponding rates in young group (18-44 years) were lower (50.94%, 35.85%, 24.53%). Improving treatment coverage and efficacy should be the focus of HBP prevention in rural areas in China. PMID:26490298

  12. Combining Aspirin with Cholecalciferol (Vitamin D3) – A Potential New Tool for Controlling Possum Populations

    PubMed Central

    Morgan, David R.; Arrow, Jane; Smith, Mark P.

    2013-01-01

    The introduced Australian brushtail possum is a major vertebrate pest in New Zealand, with impacts on conservation and agriculture being managed largely through poisoning operations. Cholecalciferol (vitamin D3) is registered for use in controlling possums and despite its many advantages it is expensive and relatively inhumane. Combination of a high proportion of aspirin with a low proportion of cholecalciferol was effective in killing high proportions of groups of acclimatised, caged possums: this is attributed to both an unexpectedly high toxicity of the type of cholecalciferol used, and a proposed synergistic mechanism between the two compounds. Death was caused by localised damage to heart ventricles by aspirin, and inhibition of tissue repair by both aspirin and cholecalciferol. The observed toxicosis had lower impact on the welfare of possums than either compound administered alone, particularly aspirin alone. Residue analyses of bait remains in the GI tract suggested a low risk of secondary poisoning by either compound. The combination of cholecalciferol and aspirin has the potential to meet key requirements of cost-effectiveness and humaneness in controlling possum populations, but the effect of the combination in non-target species has yet to be tested. PMID:23950982

  13. Risk factors for operated carpal tunnel syndrome: a multicenter population-based case-control study

    PubMed Central

    Mattioli, Stefano; Baldasseroni, Alberto; Bovenzi, Massimo; Curti, Stefania; Cooke, Robin MT; Campo, Giuseppe; Barbieri, Pietro G; Ghersi, Rinaldo; Broccoli, Marco; Cancellieri, Maria Pia; Colao, Anna Maria; dell'Omo, Marco; Fateh-Moghadam, Pirous; Franceschini, Flavia; Fucksia, Serenella; Galli, Paolo; Gobba, Fabriziomaria; Lucchini, Roberto; Mandes, Anna; Marras, Teresa; Sgarrella, Carla; Borghesi, Stefano; Fierro, Mauro; Zanardi, Francesca; Mancini, Gianpiero; Violante, Francesco S

    2009-01-01

    Background Carpal tunnel syndrome (CTS) is a socially and economically relevant disease caused by compression or entrapment of the median nerve within the carpal tunnel. This population-based case-control study aims to investigate occupational/non-occupational risk factors for surgically treated CTS. Methods Cases (n = 220) aged 18-65 years were randomly drawn from 13 administrative databases of citizens who were surgically treated with carpal tunnel release during 2001. Controls (n = 356) were randomly sampled from National Health Service registry records and were frequency matched by age-gender-specific CTS hospitalization rates. Results At multivariate analysis, risk factors were blue-collar/housewife status, BMI ≥ 30 kg/m2, sibling history of CTS and coexistence of trigger finger. Being relatively tall (cut-offs based on tertiles: women ≥165 cm; men ≥175 cm) was associated with lower risk. Blue-collar work was a moderate/strong risk factor in both sexes. Raised risks were apparent for combinations of biomechanical risk factors that included frequent repetitivity and sustained force. Conclusion This study strongly underlines the relevance of biomechanical exposures in both non-industrial and industrial work as risk factors for surgically treated CTS. PMID:19758429

  14. Free-Roaming Dog Population Estimation and Status of the Dog Population Management and Rabies Control Program in Dhaka City, Bangladesh

    PubMed Central

    Tenzin, Tenzin; Ahmed, Rubaiya; Debnath, Nitish C.; Ahmed, Garba; Yamage, Mat

    2015-01-01

    Beginning January 2012, a humane method of dog population management using a Catch-Neuter-Vaccinate-Release (CNVR) program was implemented in Dhaka City, Bangladesh as part of the national rabies control program. To enable this program, the size and distribution of the free-roaming dog population needed to be estimated. We present the results of a dog population survey and a pilot assessment of the CNVR program coverage in Dhaka City. Free-roaming dog population surveys were undertaken in 18 wards of Dhaka City on consecutive days using mark-resight methods. Data was analyzed using Lincoln-Petersen index-Chapman correction methods. The CNVR program was assessed over the two years (2012–2013) whilst the coverage of the CNVR program was assessed by estimating the proportion of dogs that were ear-notched (processed dogs) via dog population surveys. The free-roaming dog population was estimated to be 1,242 (95 % CI: 1205–1278) in the 18 sampled wards and 18,585 dogs in Dhaka City (52 dogs/km2) with an estimated human-to-free-roaming dog ratio of 828:1. During the two year CNVR program, a total of 6,665 dogs (3,357 male and 3,308 female) were neutered and vaccinated against rabies in 29 of the 92 city wards. A pilot population survey indicated a mean CNVR coverage of 60.6% (range 19.2–79.3%) with only eight wards achieving > 70% coverage. Given that the coverage in many neighborhoods was below the WHO-recommended threshold level of 70% for rabies eradications and since the CNVR program takes considerable time to implement throughout the entire Dhaka City area, a mass dog vaccination program in the non-CNVR coverage area is recommended to create herd immunity. The findings from this study are expected to guide dog population management and the rabies control program in Dhaka City and elsewhere in Bangladesh. PMID:25978406

  15. Startle Modification and P50 Gating in Schizophrenia Patients and Controls: Russian Population.

    PubMed

    Storozheva, Zinaida I; Kirenskaya, Anna V; Novototsky-Vlasov, Vladimir Y; Telesheva, Klavdia Y; Pletnikov, Mikhail

    2016-01-01

    Prepulse modification of the acoustic startle response (ASR) and P50 gating are potential neurophysiological endophenotypes of schizophrenia and may be used in the construction of valid clinical biomarkers. Such approach requires a large amount of data obtained in the representative samples from different gender, socio-typological and ethnic groups, replicating studies using the similar protocols and meta-analyses. This is a replication study of ASR and the first study of P50 suppression in Russian patients with schizophrenia (n = 28) and healthy controls (n = 25). ASR and P50 were estimated according to standard protocols. Patients exhibited increased baseline ASR latency (d = 0.35, p = .026) and reduced prepulse inhibition (PPI) at 60 ms interval (d = 0.39, p = .003) and 120 ms interval (d = 0.37, p = .005) relative to controls. In the P50 test patients displayed greater S2 response amplitude (d = 0.24, p = .036) and deficit of P50 suppression (d = 0.43, p = .001). No correlations of PPI and P50 suppression were found in both groups. Only in controls prepulse ASR facilitation (at 2500 ms interval) positively correlated with P50 suppression (r = -.514, p = .013). In patients PPI displayed significant correlations with Difficulty in abstract thinking (N5: r = -.49, p = .005) and Hallucination (P3: r = .40, p = .036) PANSS scales. Logistic regression showed that the combination of PPI and P50 suppression could serve as a diagnostic predictor. Obtained results demonstrated that both PPI and P50 could be regarded as potential schizophrenia biomarkers in Russian population. PMID:26936103

  16. Association Between Zolpidem Use and Glaucoma Risk: A Taiwanese Population-Based Case-Control Study

    PubMed Central

    Ho, Yi-Hao; Chang, Yue-Cune; Huang, Wei-Cheng; Chen, Hsin-Yi; Lin, Che-Chen; Sung, Fung-Chang

    2015-01-01

    Background To date, the relationship between zolpidem use and subsequent risk of glaucoma in a Taiwanese population has not been assessed. Methods We used data from the National Health Insurance system to investigate whether zolpidem use was related to glaucoma risk. A 1:4 matched case-control study was conducted. The cases were patients newly diagnosed with glaucoma from 2001 to 2010. The controls were randomly selected non-glaucoma subjects matched by sex and age (±5 years). Zolpidem exposure and/or the average dosage of zolpidem used (mg/year) were evaluated. Medical comorbidities were considered as confounding factors. Multiple logistic regression models were used to evaluate the potential risk of zolpidem exposure on glaucoma with/without adjustment for the effects of confounding variables. Results The exposure rate of zolpidem use in the glaucoma group was significantly higher than that of the control group (2.8% vs. 2.0%, P < 0.0001). The adjusted odds ratio (OR) of the risk of glaucoma for those with zolpidem use vs. those without was 1.19 (95% confidence interval [CI], 1.02–1.38). Compared to non-zolpidem users, zolpidem users with an average dose of more than 200 mg/year had significantly increased risk of glaucoma (OR 1.31, 95% CI 1.03–1.68). Conclusions This study suggests that the use of zolpidem might increase the risk of subsequent glaucoma. Further confirmatory studies are recommended to clarify this important issue. PMID:25720944

  17. Comparison of two populations of the pantropical predator Amblyseius largoensis (Acari: Phytoseiidae) for biological control of Raoiella indica (Acari: Tenuipalpidae).

    PubMed

    Domingos, Cleiton A; Oliveira, Leandro O; de Morais, Elisângela G F; Navia, Denise; de Moraes, Gilberto J; Gondim, Manoel G C

    2013-05-01

    The red palm mite, Raoiella indica Hirst (Acari: Tenuipalpidae), was recently introduced in the Americas. It spread quickly throughout coconut palm growing areas, expanding considerably its host range. The invasion of this species has caused high economic impact in several countries. In Brazil, extensive areas are expected to be affected. For logistical reasons and other concerns, chemical control does not seem desirable for the control of this pest in most Latin American countries. Biological control of R. indica by introducing exotic natural enemies seems to be an important control measure to be considered. Surveys in many countries have shown that Amblyseius largoensis (Muma) (Acari: Phytoseiidae) is a very common predator on coconut palms. This study compared the biology of a population of A. largoensis found for a long time in association with R. indica in La Reunion Island (Indian Ocean) with a population from Roraima State (northern Brazil), where R. indica was first found about two and a half years ago. No significant differences were observed between populations in relation to the duration of different immature stages or total survivorship. However, the oviposition period, prey consumption and net reproductive rate were significantly higher for the La Reunion population, warranting further investigation to determine whether that population should be released in Roraima to control the pest.

  18. Comparison of two populations of the pantropical predator Amblyseius largoensis (Acari: Phytoseiidae) for biological control of Raoiella indica (Acari: Tenuipalpidae).

    PubMed

    Domingos, Cleiton A; Oliveira, Leandro O; de Morais, Elisângela G F; Navia, Denise; de Moraes, Gilberto J; Gondim, Manoel G C

    2013-05-01

    The red palm mite, Raoiella indica Hirst (Acari: Tenuipalpidae), was recently introduced in the Americas. It spread quickly throughout coconut palm growing areas, expanding considerably its host range. The invasion of this species has caused high economic impact in several countries. In Brazil, extensive areas are expected to be affected. For logistical reasons and other concerns, chemical control does not seem desirable for the control of this pest in most Latin American countries. Biological control of R. indica by introducing exotic natural enemies seems to be an important control measure to be considered. Surveys in many countries have shown that Amblyseius largoensis (Muma) (Acari: Phytoseiidae) is a very common predator on coconut palms. This study compared the biology of a population of A. largoensis found for a long time in association with R. indica in La Reunion Island (Indian Ocean) with a population from Roraima State (northern Brazil), where R. indica was first found about two and a half years ago. No significant differences were observed between populations in relation to the duration of different immature stages or total survivorship. However, the oviposition period, prey consumption and net reproductive rate were significantly higher for the La Reunion population, warranting further investigation to determine whether that population should be released in Roraima to control the pest. PMID:23100107

  19. Population based case–control study of serious non-fatal motorcycle crashes

    PubMed Central

    2013-01-01

    Background Motorcycle sales, registration and use are increasing in many countries. The epidemiological literature on risk factors for motorcycle injury is becoming outdated, due to changes in rider demography, licensing regulations, traffic mix and density, road environments, and motorcycle designs and technologies. Further, the potential contribution of road infrastructure and travel speed has not yet been examined. Methods/design A population based case–control study together with a nested case-crossover study is planned. Cases will be motorcycle riders who are injured but not killed in a motorcycle crash on a public road within 150 km radius of Melbourne, Australia, and admitted to one of the study hospitals. Controls will be motorcycle riders who ride through the crash site on the same type of day (weekday or weekend) within an hour of the crash time. Data on rider, bike, and trip characteristics will be collected from the participants by questionnaire. Data on crash site characteristics will be collected in a structured site inspection, and travel speed for the cases will be estimated from these data. Travel speed for the controls will be measured prior to recruitment with a radar traffic detection device as they ride through the crash site. Control sites for the case-crossover study will be selected 1 km upstream from the crash site and matched on either intersection status or road curvature (either straight or cornered). If the initial site selected does not match the case site on these characteristics, then the closest matching site on the case route will be selected. Conditional multivariate logistic regression models will be used to compare risk between the matched case and control riders and to examine associations between road infrastructure and road environment characteristics and crash occurrence. Interactions between type of site and speed will be tested to determine if site type is an effect modifier of the relationship between speed and crash

  20. Suicide and hospitalization for mental disorders in Sweden: a population-based case-control study.

    PubMed

    Reutfors, Johan; Brandt, Lena; Ekbom, Anders; Isacsson, Göran; Sparén, Pär; Osby, Urban

    2010-09-01

    The aim of this study was to estimate suicide risk during hospitalization and in the year following discharge for patients with mental disorders. All suicide cases in Sweden 18 years and older, between 1991 and 2003 (N=20,675; 70% male), were individually matched to 10 controls from the general Swedish population. Discharge diagnoses in the year before suicide of any mental disorder, mood disorder, schizophrenia spectrum disorder, and alcohol use disorder were identified from the Swedish Patient Register. Highest suicide risk during hospitalization and in the year following discharge was found for mood disorder [odds ratio (OR) 55 (95% CI, 47-65) for men and 86 (95% CI, 70-107) for women], with the risk peaking in the first week following discharge [OR 177 (95% CI, 78-401) for men and OR 268 (95% CI, 85-846) for women]. Compared to that for mood disorder, the suicide risk for schizophrenia spectrum disorder and alcohol use disorder was about half and more constant over time. The majority of suicide victims with a psychiatric diagnosis had been discharged from psychiatric treatment more than a month before the suicide. Over time, a constant proportion of 25% of the suicide victims had been hospitalized with a mental disorder in the year before suicide (23% of males and 31% of females), despite a significant decrease in psychiatric hospitalizations in the population. In conclusion, suicide risk was found to vary by type of mental disorder, time since discharge, and sex. This should be taken into account when planning suicide preventive efforts.

  1. Naturally Occurring Incompatibilities between Different Culex pipiens pallens Populations as the Basis of Potential Mosquito Control Measures

    PubMed Central

    Chen, Lin; Zhu, Changliang; Zhang, Donghui

    2013-01-01

    Background Vector-borne diseases remain a threat to public health, especially in tropical countries. The incompatible insect technique has been explored as a potential control strategy for several important insect vectors. However, this strategy has not been tested in Culex pipiens pallens, the most prevalent mosquito species in China. Previous works used introgression to generate new strains that matched the genetic backgrounds of target populations while harboring a new Wolbachia endosymbiont, resulting in mating competitiveness and cytoplasmic incompatibility. The generation of these incompatible insects is often time-consuming, and the long-term stability of the newly created insect-Wolbachia symbiosis is uncertain. Considering the wide distribution of Cx. pipiens pallens and hence possible isolation of different populations, we sought to test for incompatibilities between natural populations and the possibility of exploiting these incompatibilities as a control strategy. Methodology/Principal Findings Three field populations were collected from three geographic locations in eastern China. Reciprocal cross results showed that bi-directional patterns of incompatibility existed between some populations. Mating competition experiments indicated that incompatible males could compete with cognate males in mating with females, leading to reduced overall fecundity. F1 offspring from incompatible crosses maintained their maternal crossing types. All three populations tested positive for Wolbachia. Removal of Wolbachia by tetracycline rendered matings between these populations fully compatible. Conclusions/Significance Our findings indicate that naturally occurring patterns of cytoplasmic incompatibility between Cx. pipiens pallens populations can be the basis of a control strategy for this important vector species. The observed incompatibilities are caused by Wolbachia. More tests including field trials are warranted to evaluate the feasibility of this strategy as a

  2. Two in one: cryptic species discovered in biological control agent populations using molecular data and crossbreeding experiments.

    PubMed

    Paterson, Iain D; Mangan, Rosie; Downie, Douglas A; Coetzee, Julie A; Hill, Martin P; Burke, Ashley M; Downey, Paul O; Henry, Thomas J; Compton, Stephe G

    2016-09-01

    There are many examples of cryptic species that have been identified through DNA-barcoding or other genetic techniques. There are, however, very few confirmations of cryptic species being reproductively isolated. This study presents one of the few cases of cryptic species that has been confirmed to be reproductively isolated and therefore true species according to the biological species concept. The cryptic species are of special interest because they were discovered within biological control agent populations. Two geographically isolated populations of Eccritotarsus catarinensis (Carvalho) [Hemiptera: Miridae], a biological control agent for the invasive aquatic macrophyte, water hyacinth, Eichhornia crassipes (Mart.) Solms [Pontederiaceae], in South Africa, were sampled from the native range of the species in South America. Morphological characteristics indicated that both populations were the same species according to the current taxonomy, but subsequent DNA analysis and breeding experiments revealed that the two populations are reproductively isolated. Crossbreeding experiments resulted in very few hybrid offspring when individuals were forced to interbreed with individuals of the other population, and no hybrid offspring were recorded when a choice of mate from either population was offered. The data indicate that the two populations are cryptic species that are reproductively incompatible. Subtle but reliable diagnostic characteristics were then identified to distinguish between the two species which would have been considered intraspecific variation without the data from the genetics and interbreeding experiments. These findings suggest that all consignments of biological control agents from allopatric populations should be screened for cryptic species using genetic techniques and that the importation of multiple consignments of the same species for biological control should be conducted with caution. PMID:27648231

  3. Accounting for Unmeasured Population Substructure in Case-Control Studies of Genetic Association Using a Novel Latent-Class Model

    PubMed Central

    Satten, Glen A.; Flanders, W. Dana; Yang, Quanhe

    2001-01-01

    We propose a novel latent-class approach to detect and account for population stratification in a case-control study of association between a candidate gene and a disease. In our approach, population substructure is detected and accounted for using data on additional loci that are in linkage equilibrium within subpopulations but have alleles that vary in frequency between subpopulations. We have tested our approach using simulated data based on allele frequencies in 12 short tandem repeat (STR) loci in four populations in Argentina. PMID:11170894

  4. Genetic variation between two Tibetan macaque (Macaca thibetana) populations in the eastern China based on mitochondrial DNA control region sequences.

    PubMed

    Yao, Yongfang; Zhong, Lijing; Liu, Bofeng; Li, Jiayi; Ni, Qingyong; Xu, Huailiang

    2013-06-01

    Tibetan macaque (Macaca thibetana) is a threatened primate species endemic to China. Population genetic and phylogenetic analyses were conducted in 66 Tibetan individuals from Sichuan (SC), Huangshan (HS), and Fujian (FJ) based on a 477-bp fragment of mitochondrial DNA control region. Four new haplotypes were defined, and a relatively high level of genetic diversity was first observed in FJ populations (Hd = 0.7661). Notably, a continuous approximately 10 bp-fragment deletion was observed near the 5' end of the mtDNA control region of both HS and FJ populations when compared with that of SC population, and a sharing haplotype was found between the two populations, revealing a closer genetic relationship. However, significant genetic differentiation (FST = 0.8700) and more poor gene exchange (Nm < 1) had occurred among three populations. This study mainly provide a further insight into the genetic relationship between HS and FJ Tibetan macaque populations, but it may be necessary to carry out further study with extra samples from other locations in the geographic coverage of the two subspecies (M. thibetana pullus and M. thibetana huangshanensis).

  5. Conditioning adaptive combination of P-values method to analyze case-parent trios with or without population controls.

    PubMed

    Lin, Wan-Yu; Liang, Yun-Chieh

    2016-01-01

    Detection of rare causal variants can help uncover the etiology of complex diseases. Recruiting case-parent trios is a popular study design in family-based studies. If researchers can obtain data from population controls, utilizing them in trio analyses can improve the power of methods. The transmission disequilibrium test (TDT) is a well-known method to analyze case-parent trio data. It has been extended to rare-variant association testing (abbreviated as "rvTDT"), with the flexibility to incorporate population controls. The rvTDT method is robust to population stratification. However, power loss may occur in the conditioning process. Here we propose a "conditioning adaptive combination of P-values method" (abbreviated as "conADA"), to analyze trios with/without unrelated controls. By first truncating the variants with larger P-values, we decrease the vulnerability of conADA to the inclusion of neutral variants. Moreover, because the test statistic is developed by conditioning on parental genotypes, conADA generates valid statistical inference in the presence of population stratification. With regard to statistical methods for next-generation sequencing data analyses, validity may be hampered by population stratification, whereas power may be affected by the inclusion of neutral variants. We recommend conADA for its robustness to these two factors (population stratification and the inclusion of neutral variants). PMID:27341039

  6. Conditioning adaptive combination of P-values method to analyze case-parent trios with or without population controls

    PubMed Central

    Lin, Wan-Yu; Liang, Yun-Chieh

    2016-01-01

    Detection of rare causal variants can help uncover the etiology of complex diseases. Recruiting case-parent trios is a popular study design in family-based studies. If researchers can obtain data from population controls, utilizing them in trio analyses can improve the power of methods. The transmission disequilibrium test (TDT) is a well-known method to analyze case-parent trio data. It has been extended to rare-variant association testing (abbreviated as “rvTDT”), with the flexibility to incorporate population controls. The rvTDT method is robust to population stratification. However, power loss may occur in the conditioning process. Here we propose a “conditioning adaptive combination of P-values method” (abbreviated as “conADA”), to analyze trios with/without unrelated controls. By first truncating the variants with larger P-values, we decrease the vulnerability of conADA to the inclusion of neutral variants. Moreover, because the test statistic is developed by conditioning on parental genotypes, conADA generates valid statistical inference in the presence of population stratification. With regard to statistical methods for next-generation sequencing data analyses, validity may be hampered by population stratification, whereas power may be affected by the inclusion of neutral variants. We recommend conADA for its robustness to these two factors (population stratification and the inclusion of neutral variants). PMID:27341039

  7. How a network of conservationists and population control activists created the contemporary US anti-immigration movement.

    PubMed

    Normandin, Sebastian; Valles, Sean A

    2015-06-01

    Continuing historical narratives of the early twentieth century nexus of conservationism, eugenics, and nativism (exemplified by Madison Grant), this paper traces the history of the contemporary US anti-immigration movement's roots in environmentalism and global population control activism, through an exploration of the thoughts and activities of the activist, John Tanton, who has been called "the most influential unknown man in America." We explore the "neo-Malthusian" ideas that sparked a seminal moment for population control advocacy in the late 1960s and early 1970s, leading to the creation of Zero Population Growth (ZPG). After rising to the presidency of ZPG, Tanton, and ZPG spun off the Federation for American Immigration Reform. After leaving ZPG's leadership, Tanton created additional anti-immigration advocacy groups and built up connections with existing organizations such as the Pioneer Fund. We trace Tanton's increasingly radical conservative network of anti-immigration advocates, conservationists, and population control activists to the present day. Tanton's archived papers illustrate, among other things, his interactions with collaborators such as ecologist Garrett Hardin (author of the famous "Tragedy of the Commons") and his documented interest in reviving eugenics. We contend that this history of Tanton's network provides key insights into understanding how there came to be an overlap between the ideologies and activist communities of immigration restrictionism, population control, conservationism and eugenics. PMID:26026333

  8. How a network of conservationists and population control activists created the contemporary US anti-immigration movement.

    PubMed

    Normandin, Sebastian; Valles, Sean A

    2015-06-01

    Continuing historical narratives of the early twentieth century nexus of conservationism, eugenics, and nativism (exemplified by Madison Grant), this paper traces the history of the contemporary US anti-immigration movement's roots in environmentalism and global population control activism, through an exploration of the thoughts and activities of the activist, John Tanton, who has been called "the most influential unknown man in America." We explore the "neo-Malthusian" ideas that sparked a seminal moment for population control advocacy in the late 1960s and early 1970s, leading to the creation of Zero Population Growth (ZPG). After rising to the presidency of ZPG, Tanton, and ZPG spun off the Federation for American Immigration Reform. After leaving ZPG's leadership, Tanton created additional anti-immigration advocacy groups and built up connections with existing organizations such as the Pioneer Fund. We trace Tanton's increasingly radical conservative network of anti-immigration advocates, conservationists, and population control activists to the present day. Tanton's archived papers illustrate, among other things, his interactions with collaborators such as ecologist Garrett Hardin (author of the famous "Tragedy of the Commons") and his documented interest in reviving eugenics. We contend that this history of Tanton's network provides key insights into understanding how there came to be an overlap between the ideologies and activist communities of immigration restrictionism, population control, conservationism and eugenics.

  9. Web Intervention for Adolescents Affected by Disaster: Population-Based Randomized Controlled Trial

    PubMed Central

    Ruggiero, Kenneth J.; Price, Matthew; Adams, Zachary; Stauffacher, Kirstin; McCauley, Jenna; Danielson, Carla Kmett; Knapp, Rebecca; Hanson, Rochelle F.; Davidson, Tatiana M.; Amstadter, Ananda B.; Carpenter, Matthew J.; Saunders, Benjamin E.; Kilpatrick, Dean G.; Resnick, Heidi S.

    2015-01-01

    Objective To assess the efficacy of Bounce Back Now (BBN), a modular, web-based intervention for disaster-affected adolescents and their parents. Method A population-based randomized controlled trial used address-based sampling to enroll 2,000 adolescents and parents from communities affected by tornadoes in Joplin, MO, and Alabama. Data collection via baseline and follow-up semi-structured telephone interviews was completed between September 2011 and August 2013. All families were invited to access the BBN study web portal irrespective of mental health status at baseline. Families who accessed the web portal were assigned randomly to 3 groups: (1) BBN, which featured modules for adolescents and parents targeting adolescents’ mental health symptoms; (2) BBN plus additional modules targeting parents’ mental health symptoms; or (3) assessment only. The primary outcomes were adolescent symptoms of posttraumatic stress disorder (PTSD) and depression. Results Nearly 50% of families accessed the web portal. Intent-to-treat analyses revealed time × condition interactions for PTSD symptoms (B=−0.24, SE=0.08, p<.01) and depressive symptoms (B=−0.23, SE=0.09, p<.01). Post-hoc comparisons revealed fewer PTSD and depressive symptoms for adolescents in the experimental vs. control conditions at 12-month follow-up (PTSD: B=−0.36, SE=0.19, p=.06; depressive symptoms: B=−0.42, SE=0.19, p=0.03). A time × condition interaction also was found favoring the BBN vs. BBN + parent self-help condition for PTSD symptoms (B=0.30, SE=0.12, p=.02), but not depressive symptoms (B=0.12, SE=0.12, p=.33). Conclusion Results supported the feasibility and initial efficacy of BBN as a scalable disaster mental health intervention for adolescents. Technology-based solutions have tremendous potential value if found to reduce the mental health burden of disasters. PMID:26299292

  10. Environmental risk factors in paediatric inflammatory bowel diseases: a population based case control study

    PubMed Central

    Baron, S; Turck, D; Leplat, C; Merle, V; Gower-Rousseau, C; Marti, R; Yzet, T; Lerebours, E; Dupas, J-L; Debeugny, S; Salomez, J-L; Cortot, A; Colombel, J-F

    2005-01-01

    Background: Environmental exposures in early life have been implicated in the aetiology of inflammatory bowel disease. Objective: To examine environmental risk factors prior to the development of inflammatory bowel disease in a paediatric population based case control study. Methods: A total of 222 incident cases of Crohn’s disease and 60 incident cases of ulcerative colitis occurring before 17 years of age between January 1988 and December 1997 were matched with one control subject by sex, age, and geographical location. We recorded 140 study variables in a questionnaire that covered familial history of inflammatory bowel disease, events during the perinatal period, infant and child diet, vaccinations and childhood diseases, household amenities, and the family’s socioeconomic status. Results: In a multivariate model, familial history of inflammatory bowel disease (odds ratio (OR) 4.3 (95% confidence interval 2.3–8)), breast feeding (OR 2.1 (1.3–3.4)), bacille Calmette-Guerin vaccination (OR 3.6 (1.1–11.9)), and history of eczema (OR 2.1 (1–4.5)) were significant risk factors for Crohn’s disease whereas regular drinking of tap water was a protective factor (OR 0.56 (0.3–1)). Familial history of inflammatory bowel disease (OR 12.5 (2.2–71.4)), disease during pregnancy (OR 8.9 (1.5–52)), and bedroom sharing (OR 7.1 (1.9–27.4)) were risk factors for ulcerative colitis whereas appendicectomy was a protective factor (OR 0.06 (0.01–0.36)). Conclusions: While family history and appendicectomy are known risk factors, changes in risk based on domestic promiscuity, certain vaccinations, and dietary factors may provide new aetiological clues. PMID:15710983

  11. Air Pollution and the Risk of Cardiac Defects: A Population-Based Case-Control Study.

    PubMed

    Hwang, Bing-Fang; Lee, Yungling Leo; Jaakkola, Jouni J K

    2015-11-01

    Previous epidemiologic studies have assessed the role of the exposure to ambient air pollution in the development of cardiac birth defects, but they have provided somewhat inconsistent results. To assess the associations between exposure to ambient air pollutants and the risk of cardiac defects, a population-based case-control study was conducted using 1087 cases of cardiac defects and a random sample of 10,870 controls from 1,533,748 Taiwanese newborns in 2001 to 2007.Logistic regression was performed to calculate odds ratios for 10 ppb increases in O3 and 10 μg/m increases in PM10. In addition, we compared the risk of cardiac defects in 4 categories-high exposure (>75th percentile); medium exposure (75th to 50th percentile); low exposure (<50th-25th percentile); reference (<25th percentile) based on the distribution of each pollutant. The risks of ventricular septal defects (VSD), atrial septal defects (ASD), and patent ductus arteriosus (PDA) were associated with 10 ppb increases in O3 exposure during the first 3 gestational months among term and preterm babies. In comparison between high PM10 exposure and reference category, there were statistically significant elevations in the effect estimates of ASD for all and terms births. In addition, there was a negative or weak association between SO2, NO2, CO, and cardiac defects.The study proved that exposure to outdoor air O3 and PM10 during the first trimester of gestation may increase the risk of VSD, ASD, and PDA. PMID:26554783

  12. Chronic constipation and co-morbidities: A prospective population-based nested case-control study

    PubMed Central

    Choung, Rok S; Rey, Enrique; Richard Locke, G; Schleck, Cathy D; Baum, Charles; Zinsmeister, Alan R

    2015-01-01

    Background Chronic constipation (CC) is common in the community but surprisingly little is known about relevant gastro-intestinal (GI) and non-GI co-morbidities. Objective The purpose of this study was to assess the epidemiology of CC and in particular provide new insights into the co-morbidities linked to this condition. Methods In a prospective, population-based nested case-control study, a cohort of randomly selected community residents (n = 8006) were mailed a validated self-report gastrointestinal symptom questionnaire. CC was defined according to Rome III criteria. Medical records of each case and control were abstracted to identify potential CC comorbidities. Results Altogether 3831 (48%) subjects returned questionnaires; 307 met criteria for CC. Age-adjusted prevalence in females was 8.7 (95% confidence interval (CI) 7.1–10.3) and 5.1 (3.6–6.7) in males, per 100 persons. CC was not associated with most GI pathology, but the odds for constipation were increased in subjects with anal surgery relative to those without (odds ratio (OR) = 3.3, 95% CI 1.2–9.1). In those with constipation vs those without, neurological diseases including Parkinson’s disease (OR = 6.5, 95% CI 2.9–14.4) and multiple sclerosis (OR = 5.5, 95% CI 1.9–15.8) showed significantly increased odds for chronic constipation, adjusting for age and gender. In addition, modestly increased odds for chronic constipation in those with angina (OR = 1.4, 95% CI 1.1–1.9) and myocardial infarction (OR = 1.5, 95% CI 1.0–2.4) were observed. Conclusions Neurological and cardiovascular diseases are linked to constipation but in the community constipation is unlikely to account for most lower GI pathology. PMID:26966534

  13. Occupational, domestic and environmental mesothelioma risks in the British population: a case–control study

    PubMed Central

    Rake, C; Gilham, C; Hatch, J; Darnton, A; Hodgson, J; Peto, J

    2009-01-01

    We obtained lifetime occupational and residential histories by telephone interview with 622 mesothelioma patients (512 men, 110 women) and 1420 population controls. Odds ratios (ORs) were converted to lifetime risk (LR) estimates for Britons born in the 1940s. Male ORs (95% confidence interval (CI)) relative to low-risk occupations for >10 years of exposure before the age of 30 years were 50.0 (25.8–96.8) for carpenters (LR 1 in 17), 17.1 (10.3–28.3) for plumbers, electricians and painters, 7.0 (3.2–15.2) for other construction workers, 15.3 (9.0–26.2) for other recognised high-risk occupations and 5.2 (3.1–8.5) in other industries where asbestos may be encountered. The LR was similar in apparently unexposed men and women (∼1 in 1000), and this was approximately doubled in exposed workers' relatives (OR 2.0, 95% CI 1.3–3.2). No other environmental hazards were identified. In all, 14% of male and 62% of female cases were not attributable to occupational or domestic asbestos exposure. Approximately half of the male cases were construction workers, and only four had worked for more than 5 years in asbestos product manufacture. PMID:19259084

  14. The Impact of the Nurses’ Health Study on Population Health: Prevention, Translation, and Control

    PubMed Central

    Philpott, Sydney E.; Hankinson, Susan E.

    2016-01-01

    Objectives. To summarize the overall impact of the Nurses’ Health Study (NHS) over the past 40 years on the health of populations through its contributions on prevention, translation, and control. Methods. We performed a narrative review of the findings of the NHS, NHS II, and NHS3 between 1976 and 2016. Results. The NHS has generated significant findings about the associations between (1) smoking and type 2 diabetes, cardiovascular diseases, colorectal and pancreatic cancer, psoriasis, multiple sclerosis, and eye diseases; (2) physical activity and cardiovascular diseases, breast cancer, psoriasis, and neurodegeneration; (3) obesity and cardiovascular diseases, numerous cancer sites, psoriasis, multiple sclerosis, kidney stones, and eye diseases; (4) oral contraceptives and cardiovascular disease, melanoma, and breast, colorectal, and ovarian cancer; (5) hormone therapy and cardiovascular diseases, breast and endometrial cancer, and neurodegeneration; (6) endogenous hormones and breast cancer; (7) dietary factors and type 2 diabetes, cardiovascular diseases, breast and pancreatic cancer, non-Hodgkin’s lymphoma, neurodegeneration, multiple sclerosis, kidney stones, and eye diseases; and (8) sleep and shift work and chronic diseases. Conclusions. The NHS findings have influenced public health policy and practice both locally and globally to improve women’s health. PMID:27459441

  15. Host Control of Symbiont Natural Product Chemistry in Cryptic Populations of the Tunicate Lissoclinum patella

    PubMed Central

    Kwan, Jason C.; Tianero, Ma. Diarey B.; Donia, Mohamed S.; Wyche, Thomas P.; Bugni, Tim S.; Schmidt, Eric W.

    2014-01-01

    Natural products (secondary metabolites) found in marine invertebrates are often thought to be produced by resident symbiotic bacteria, and these products appear to play a major role in the symbiotic interaction of bacteria and their hosts. In these animals, there is extensive variation, both in chemistry and in the symbiotic bacteria that produce them. Here, we sought to answer the question of what factors underlie chemical variation in the ocean. As a model, we investigated the colonial tunicate Lissoclinum patella because of its rich and varied chemistry and its broad geographic range. We sequenced mitochondrial cytochrome c oxidase 1 (COXI) genes, and found that animals classified as L. patella fall into three phylogenetic groups that may encompass several cryptic species. The presence of individual natural products followed the phylogenetic relationship of the host animals, even though the compounds are produced by symbiotic bacteria that do not follow host phylogeny. In sum, we show that cryptic populations of animals underlie the observed chemical diversity, suggesting that the host controls selection for particular secondary metabolite pathways. These results imply novel approaches to obtain chemical diversity from the oceans, and also demonstrate that the diversity of marine natural products may be greatly impacted by cryptic local extinctions. PMID:24788869

  16. Insect population control by homing endonuclease-based gene drive: an evaluation in Drosophila melanogaster.

    PubMed

    Chan, Yuk-Sang; Naujoks, Daniel A; Huen, David S; Russell, Steven

    2011-05-01

    Insects play a major role as vectors of human disease as well as causing significant agricultural losses. Harnessing the activity of customized homing endonuclease genes (HEGs) has been proposed as a method for spreading deleterious mutations through populations with a view to controlling disease vectors. Here, we demonstrate the feasibility of this method in Drosophila melanogaster, utilizing the well-characterized HEG, I-SceI. In particular, we show that high rates of homing can be achieved within spermatogonia and in the female germline. We show that homed constructs continue to exhibit HEG activity in the subsequent generation and that the ectopic homing events required for initiating the strategy occur at an acceptable rate. We conclude that the requirements for successful deployment of a HEG-based gene drive strategy can be satisfied in a model dipteran and that there is a reasonable prospect of the method working in other dipterans. In characterizing the system we measured repair outcomes at the spermatogonial, spermatocyte, and spermatid stages of spermatogenesis. We show that homologous recombination is restricted to spermatogonia and that it immediately ceases when they become primary spermatocytes, indicating that the choice of DNA repair pathway in the Drosophila testis can switch abruptly during differentiation.

  17. Antihypertensive treatment and control in a large primary care population of 21 167 patients.

    PubMed

    Qvarnström, M; Wettermark, B; Ljungman, C; Zarrinkoub, R; Hasselström, J; Manhem, K; Sundström, A; Kahan, T

    2011-08-01

    The efficacy of antihypertensive drug therapy is undisputed, but observational studies show that few patients reach a target blood pressure <140/90 mm Hg. However, there is limited data on the drug prescribing patterns and their effectiveness in real practice. This retrospective observational survey of electronic patient records extracted data from 24 Swedish primary health-care centres, with a combined registered population of 330 000 subjects. We included all patients > 30 years with a recorded diagnosis of hypertension who consulted the centres in 2005 or 2006 (n=21 167). Main outcome measures were systolic and diastolic blood pressures, and prescribed antihypertensive drug classes. Only 27% had a blood pressure <140/90 mm Hg. The number of prescribed drugs increased with age, except among the oldest (> 90 years). Only 29% of patients given monotherapy had a blood pressure <140/90 mm Hg. Women more often received diuretics (52 vs 42%), and less often angiotensin-converting enzyme inhibitors (22 vs 33%) and calcium channel blockers (26 vs 31%) than men. β-Blockers and diuretics were the most common drug classes prescribed, independent of comorbidity. In conclusion, one out of four primary care patients with hypertension reach target blood pressure. More frequent use of drug combinations may improve blood pressure control.

  18. An ER-peroxisome tether exerts peroxisome population control in yeast.

    PubMed

    Knoblach, Barbara; Sun, Xuejun; Coquelle, Nicolas; Fagarasanu, Andrei; Poirier, Richard L; Rachubinski, Richard A

    2013-09-11

    Eukaryotic cells compartmentalize biochemical reactions into membrane-enclosed organelles that must be faithfully propagated from one cell generation to the next. Transport and retention processes balance the partitioning of organelles between mother and daughter cells. Here we report the identification of an ER-peroxisome tether that links peroxisomes to the ER and ensures peroxisome population control in the yeast Saccharomyces cerevisiae. The tether consists of the peroxisome biogenic protein, Pex3p, and the peroxisome inheritance factor, Inp1p. Inp1p bridges the two compartments by acting as a molecular hinge between ER-bound Pex3p and peroxisomal Pex3p. Asymmetric peroxisome division leads to the formation of Inp1p-containing anchored peroxisomes and Inp1p-deficient mobile peroxisomes that segregate to the bud. While peroxisomes in mother cells are not released from tethering, de novo formation of tethers in the bud assists in the directionality of peroxisome transfer. Peroxisomes are thus stably maintained over generations of cells through their continued interaction with tethers.

  19. Digital IIR Filters Design Using Differential Evolution Algorithm with a Controllable Probabilistic Population Size

    PubMed Central

    Zhu, Wu; Fang, Jian-an; Tang, Yang; Zhang, Wenbing; Du, Wei

    2012-01-01

    Design of a digital infinite-impulse-response (IIR) filter is the process of synthesizing and implementing a recursive filter network so that a set of prescribed excitations results a set of desired responses. However, the error surface of IIR filters is usually non-linear and multi-modal. In order to find the global minimum indeed, an improved differential evolution (DE) is proposed for digital IIR filter design in this paper. The suggested algorithm is a kind of DE variants with a controllable probabilistic (CPDE) population size. It considers the convergence speed and the computational cost simultaneously by nonperiodic partial increasing or declining individuals according to fitness diversities. In addition, we discuss as well some important aspects for IIR filter design, such as the cost function value, the influence of (noise) perturbations, the convergence rate and successful percentage, the parameter measurement, etc. As to the simulation result, it shows that the presented algorithm is viable and comparable. Compared with six existing State-of-the-Art algorithms-based digital IIR filter design methods obtained by numerical experiments, CPDE is relatively more promising and competitive. PMID:22808191

  20. Ecological Complexity in a Coffee Agroecosystem: Spatial Heterogeneity, Population Persistence and Biological Control

    PubMed Central

    Liere, Heidi; Jackson, Doug; Vandermeer, John

    2012-01-01

    Background Spatial heterogeneity is essential for the persistence of many inherently unstable systems such as predator-prey and parasitoid-host interactions. Since biological interactions themselves can create heterogeneity in space, the heterogeneity necessary for the persistence of an unstable system could be the result of local interactions involving elements of the unstable system itself. Methodology/Principal Findings Here we report on a predatory ladybird beetle whose natural history suggests that the beetle requires the patchy distribution of the mutualism between its prey, the green coffee scale, and the arboreal ant, Azteca instabilis. Based on known ecological interactions and the natural history of the system, we constructed a spatially-explicit model and showed that the clustered spatial pattern of ant nests facilitates the persistence of the beetle populations. Furthermore, we show that the dynamics of the beetle consuming the scale insects can cause the clustered distribution of the mutualistic ants in the first place. Conclusions/Significance From a theoretical point of view, our model represents a novel situation in which a predator indirectly causes a spatial pattern of an organism other than its prey, and in doing so facilitates its own persistence. From a practical point of view, it is noteworthy that one of the elements in the system is a persistent pest of coffee, an important world commodity. This pest, we argue, is kept within limits of control through a complex web of ecological interactions that involves the emergent spatial pattern. PMID:23029061

  1. From population control politics to chemicals: the WHO as an intermediary organization in contraceptive development.

    PubMed

    Oudshoorn, N

    1997-02-01

    Studies of laboratory work have rarely focused on the role of intermediary organizations in developing R&D activities. Most studies focus on a single university-based research laboratory or an industrial R&D unit. Moreover the rejection by social constructivist scholars of universalistic, deterministic explanations of the development of science and technology has led to an overemphasis on the local features of scientific and technological work. Based on a case study of the role of the World Health Organization (WHO) in contraceptive R&D, this paper suggests that an analysis of the role of intermediary organizations enables us to go beyond a too-narrow focus on the micro-sociological dynamics of laboratory work, to include the macro- and meso-sociological dimensions of science and technology. First, a focus on intermediary organizations enables us to learn more about the manner in which locally specific laboratory cultures are transformed into translocal research practices. This paper shows how literary technologies, and to an even greater extent material technologies, are important tools in accomplishing standardization of local laboratory cultures. Second, a focus on intermediary organizations enables us to study how concerns that go beyond the laboratory--in this case, population control policies and the agenda of the WHO--help to shape laboratory practices.

  2. Multiple Sclerosis and CCSVI: A Population-Based Case Control Study

    PubMed Central

    Patti, Francesco; Nicoletti, Alessandra; Leone, Carmela; Messina, Silvia; D’Amico, Emanuele; Lo Fermo, Salvatore; Paradisi, Vincenza; Bruno, Elisa; Quattrocchi, Graziella; Veroux, Pierfrancesco; Di Pino, Luigi; Costanzo, Luca; Zappia, Mario

    2012-01-01

    Background Chronic cerebrospinal venous insufficiency (CCSVI) has been associated to multiple sclerosis (MS). Objective To evaluate the possible association between CCSVI and MS, using a population-based control design. Methods A random cohort of 148 incident MS patients were enrolled in the study. We have also studied 20 patients with clinically isolated syndrome (CIS), 40 patients with other neurological diseases (OND), and 172 healthy controls. Transcranial (TCC) and Echo Color Doppler (ECD) were carried out in 380 subjects. A subject was considered CCSVI positive if ≥2 venous hemodynamic criteria were fulfilled. Results CCSVI was present in 28 (18.9%) of the MS patients, in 2 (10%) of CIS patients, in 11 (6.4%) of the controls, and in 2 (5%) of the OND patients. A significant association between MS and CCSVI was found with an odds ratio of 3.41 (95% confidence interval 1.63–7.13; p = 0.001). CCSVI was significantly more frequent among MS subjects with a disease duration longer than 144 months (26.1% versus 12.6% of patients with duration shorter than 144 months; p = 0.03) and among patients with secondary progressive (SP) and primary progressive (PP) forms (30.2% and 29.4, respectively) than in patients with relapsing remitting (RR) MS (14.3%). A stronger association was found considering SP and PP forms (age adjusted OR = 4.7; 95% CI 1.83–12.0, p = 0.001); the association was weaker with the RR patients (age adjusted OR = 2.58; 95%CI 1.12–5.92; p = 0.02) or not significant in CIS group (age adjusted OR = 2.04; 95%CI 0.40–10.3; p = 0.4). Conclusions A higher frequency of CCSVI has been found in MS patients; it was more evident in patients with advanced MS, suggesting that CCSVI could be related to MS disability. PMID:22870210

  3. Selection of population controls for a Salmonella case-control study in the UK using a market research panel and web-survey provides time and resource savings.

    PubMed

    Mook, P; Kanagarajah, S; Maguire, H; Adak, G K; Dabrera, G; Waldram, A; Freeman, R; Charlett, A; Oliver, I

    2016-04-01

    Timely recruitment of population controls in infectious disease outbreak investigations is challenging. We evaluated the timeliness and cost of using a market research panel as a sampling frame for recruiting controls in a case-control study during an outbreak of Salmonella Mikawasima in the UK in 2013. We deployed a web-survey by email to targeted members of a market research panel (panel controls) in parallel to the outbreak control team interviewing randomly selected public health staff by telephone and completing paper-based questionnaires (staff controls). Recruitment and completion of exposure history web-surveys for panel controls (n = 123) took 14 h compared to 15 days for staff controls (n = 82). The average staff-time cost per questionnaire for staff controls was £13·13 compared to an invoiced cost of £3·60 per panel control. Differences in the distribution of some exposures existed between these control groups but case-control studies using each group found that illness was associated with consumption of chicken outside of the home and chicken from local butchers. Recruiting market research panel controls offers time and resource savings. More rapid investigations would enable more prompt implementation of control measures. We recommend that this method of recruiting controls is considered in future investigations and assessed further to better understand strengths and limitations.

  4. Selection of population controls for a Salmonella case-control study in the UK using a market research panel and web-survey provides time and resource savings.

    PubMed

    Mook, P; Kanagarajah, S; Maguire, H; Adak, G K; Dabrera, G; Waldram, A; Freeman, R; Charlett, A; Oliver, I

    2016-04-01

    Timely recruitment of population controls in infectious disease outbreak investigations is challenging. We evaluated the timeliness and cost of using a market research panel as a sampling frame for recruiting controls in a case-control study during an outbreak of Salmonella Mikawasima in the UK in 2013. We deployed a web-survey by email to targeted members of a market research panel (panel controls) in parallel to the outbreak control team interviewing randomly selected public health staff by telephone and completing paper-based questionnaires (staff controls). Recruitment and completion of exposure history web-surveys for panel controls (n = 123) took 14 h compared to 15 days for staff controls (n = 82). The average staff-time cost per questionnaire for staff controls was £13·13 compared to an invoiced cost of £3·60 per panel control. Differences in the distribution of some exposures existed between these control groups but case-control studies using each group found that illness was associated with consumption of chicken outside of the home and chicken from local butchers. Recruiting market research panel controls offers time and resource savings. More rapid investigations would enable more prompt implementation of control measures. We recommend that this method of recruiting controls is considered in future investigations and assessed further to better understand strengths and limitations. PMID:26493476

  5. Bile acids in a multicenter, population-based case-control study of stillbirth

    PubMed Central

    Silver, Robert M.; Parker, Corette B.; Goldenberg, Robert; Reddy, Uma M.; Dudley, Donald J.; Saade, George R.; Hogue, Carol J. Rowland; Coustan, Donald; Varner, Michael W.; Koch, Matthew A.; Conway, Deborah; Bukowski, Radek; Pinar, Halit; Stoll, Barbara; Moore, Janet; Willinger, Marian

    2015-01-01

    OBJECTIVE We sought to compare bile acids in women with and without stillbirth in a population-based study. STUDY DESIGN The Stillbirth Collaborative Research Network conducted a multisite, population-based case-control study of stillbirth (fetal deaths ≥20 weeks). Maternal sera were obtained at the time of enrollment and frozen at −80° until assay for bile acids. RESULTS Assays were performed in 581 women with stillbirth and 1546 women with live births. Bile acid levels were slightly higher in women with stillbirth (geometric mean [95% confidence interval {CI}] = 3.2 [3.0–3.5]) compared to live births (2.9 [2.7–3.1], P = .0327). However, the difference was not significant after adjustment for baseline risk factors for stillbirth. The proportion of women with elevated levels (≥10 or ≥40 μmol/L) was similar in stillbirths and live births. Results were similar when the analysis was limited to subsets of stillbirths and live births. In women with stillbirths not associated with fetal anomalies or obstetric complications bile acid levels were higher than in women with term live births (geometric mean [95% CI] = 3.4 [3.0–3.8] vs 2.9 [2.7–3.0], P = .0152, unadjusted; P = .06, adjusted). However, a similar proportion of women in both groups had levels ≥10 mmol/L (10.7 vs 7.2%; odds ratio [OR], 1.54; 95% CI, 0.97–2.44; adjusted OR, 1.29; 95% CI, 0.78–2.15) and ≥40 μmol/L (1.7 vs 0.7%; OR, 2.58; 95% CI, 0.85–7.84; adjusted OR, 2.28; 95% CI, 0.79–6.56). CONCLUSION Our data do not support testing for bile acids in cases of stillbirth in the absence of clinical evidence of intrahepatic cholestasis of pregnancy. PMID:24215860

  6. Dietary patterns and colorectal cancer risk in a Korean population: A case-control study.

    PubMed

    Park, Yoon; Lee, Jeonghee; Oh, Jae Hwan; Shin, Aesun; Kim, Jeongseon

    2016-06-01

    Colorectal cancer (CRC) has been recognized as one of the major malignancies in Korea. Analyses of dietary patterns can provide insight into the complex interactions of foods, nutrients, and biologically active components within a diet, which vary among populations. We aimed to investigate the associations between dietary patterns and colorectal cancer risk in Koreans. In a study of 923 cases and 1846 controls, principal component analysis was used to identify dietary patterns based on 33 predefined food groups using a 106-item semiquantitative food frequency questionnaire (SQFFQ). The associations between dietary patterns and CRC risk were assessed using binary and polytomous logistic regression models to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Three dietary patterns (traditional, Westernized, and prudent) were derived. The proportion of total variation explained by 3 patterns was 24.2% for men and 25.3% for women. The traditional and prudent patterns were inversely associated with CRC risk [OR and 95% CI for the highest intake tertile of pattern score vs. the lowest = 0.35 (0.27-0.46) and 0.37 (0.28-0.48), respectively], whereas the Westernized pattern showed a positive association, especially among women [OR = 2.13 (1.35-3.34) for the highest tertile vs. the lowest]. A decrease in CRC risk among those with the highest intake of the prudent pattern was observed in all anatomical subsites in both men [OR = 0.36 (0.19-0.68) for proximal colon; 0.21 (0.12-0.36) for distal colon; 0.28 (0.18-0.44) for rectum] and women [OR = 0.28 (0.11-0.71); 0.27 (0.13-0.54); 0.45 (0.25-0.83)]. Our results indicate that individuals who prefer the Westernized dietary pattern should be made aware of their increased CRC risk. The traditional dietary pattern and the prudent pattern, which are rich in fruits and dairy products, are recommended for the Korean population to prevent CRC. PMID:27336862

  7. The case-only independence assumption: associations between genetic polymorphisms and smoking among controls in two population-based studies.

    PubMed

    Hodgson, M Elizabeth; Olshan, Andrew F; North, Kari E; Poole, Charles L; Zeng, Donglin; Tse, Chiu-Kit; Keku, Tope O; Galanko, Joseph; Sandler, Robert; Millikan, Robert C

    2012-01-01

    The independence assumption for a case-only analysis of statistical interaction, i. e. that genetic (G) and environmental exposures (E) are not associated in the source population, is often checked in surrogate populations. Few studies have examined G-E association in empirical data, particularly in controls from population-based studies, the type of controls expected to provide the most valid surrogate estimates of G-E association. We used controls from two population-based case-control studies to evaluate G-E independence for 43 selected genetic polymorphisms and smoking behavior. The odds ratio (OR(z)) was used to estimate G-E association and, therefore, the magnitude of bias introduced into the case-only odds ratio (COR). Odds ratios of moderate magnitude [mmOR(z)], defined as OR(z)≤0.7 or OR(z)≥1.4, were found at least one of the six smoking measures (ever, former, current, cig/day, years smoked, pack-years) for 45% and 59% of the SNPs examined in the control groups of two independently conducted North Carolina studies, respectively. Consequently, case-only estimates of G-E interaction in the context of a multiplicative benchmark would be biased for these SNPs and smoking measures. MmOR(z)s were found more often for smoking amount than smoking status. We recommend that a stand-alone case-only study should only be conducted when G-E independence can be verified for each polymorphism and exposure metric with population-specific data. Our results suggest that OR(z) is specific to each underlying population rather than an estimate of a 'universal' OR(z) for that SNP and smoking measure. Further, misspecification of smoking is likely to introduce bias into the COR.

  8. The case-only independence assumption: associations between genetic polymorphisms and smoking among controls in two population-based studies

    PubMed Central

    Hodgson, M Elizabeth; Olshan, Andrew F; North, Kari E; Poole, Charles L; Zeng, Donglin; Tse, Chiu-Kit; Keku, Tope O; Galanko, Joseph; Sandler, Robert; Millikan, Robert C

    2012-01-01

    The independence assumption for a case-only analysis of statistical interaction, i. e. that genetic (G) and environmental exposures (E) are not associated in the source population, is often checked in surrogate populations. Few studies have examined G-E association in empirical data, particularly in controls from population-based studies, the type of controls expected to provide the most valid surrogate estimates of G-E association. We used controls from two population-based case-control studies to evaluate G-E independence for 43 selected genetic polymorphisms and smoking behavior. The odds ratio (ORz) was used to estimate G-E association and, therefore, the magnitude of bias introduced into the case-only odds ratio (COR). Odds ratios of moderate magnitude [mmORz], defined as ORz≤0.7 or ORz≥1.4, were found at least one of the six smoking measures (ever, former, current, cig/day, years smoked, pack-years) for 45% and 59% of the SNPs examined in the control groups of two independently conducted North Carolina studies, respectively. Consequently, case-only estimates of G-E interaction in the context of a multiplicative benchmark would be biased for these SNPs and smoking measures. MmORzs were found more often for smoking amount than smoking status. We recommend that a stand-alone case-only study should only be conducted when G-E independence can be verified for each polymorphism and exposure metric with population-specific data. Our results suggest that ORz is specific to each underlying population rather than an estimate of a ‘universal’ ORz for that SNP and smoking measure. Further, misspecification of smoking is likely to introduce bias into the COR. PMID:23205185

  9. Nonsurgical fertility control for managing free-roaming dog populations: a review of products and criteria for field applications.

    PubMed

    Massei, Giovanna; Miller, Lowell A

    2013-11-01

    About 75% of dogs worldwide are free to roam and reproduce, thus creating locally overabundant populations. Problems caused by roaming dogs include diseases transmitted to livestock and humans, predation on livestock, attacks on humans, road traffic accidents, and nuisance behavior. Nonsurgical fertility control is increasingly advocated as more cost-effective than surgical sterilization to manage dog populations and their impact. The aims of this review were to 1) analyze trends in numbers of scientific publications on nonsurgical fertility control for dogs; 2) illustrate the spectrum of fertility inhibitors available for dogs; 3) examine how differences between confined and free-roaming dogs might affect the choice of fertility inhibitors to be used in dog population management; and 4) provide a framework of criteria to guide decisions regarding the use of nonsurgical fertility control for dog population management. The results showed that the 117 articles published between 1982 and 2011 focussed on long-term hormonal contraceptives, such as gonadotropin-releasing hormone agonists, immunocontraceptives, and male chemical sterilants. The number of articles published biennially increased from one to five papers produced in the early 1980s to 10 to 20 in the past decade. Differences between confined dogs and free-roaming dogs include reproduction and survival as well as social expectations regarding the duration of infertility, the costs of sterilization, and the responsibilities for meeting these costs. These differences are likely to dictate which fertility inhibitors will be used for confined or free-roaming dogs. The criteria regarding the use of fertility control for dog population management, presented as a decision tree, covered social acceptance, animal welfare, effectiveness, legal compliance, feasibility, and sustainability. The review concluded that the main challenges for the future are evaluating the feasibility, effectiveness, sustainability, and

  10. Major dietary patterns and risk of acute myocardial infarction in young, urban Pakistani population

    PubMed Central

    Iqbal, Romaina; Iqbal, Saleem Perwaiz; Yakub, Mohsin; Tareen, Asal Khan; Iqbal, Mohammad Perwaiz

    2015-01-01

    Objective: To investigate the role of dietary intake in the development of premature acute myocardial infarction (AMI) in a hospital-based Pakistani population in Karachi. Methods: In a case control study, 203 consecutive patients (146 males and 57 females) with their first AMI and age below 45 years were enrolled with informed consent. Similarly, 205 gender and age matched (within 3 years) healthy adults were also included as controls. Dietary intake of both cases and controls was assessed by using a simple 14-item food frequency questionnaire. Using factor analysis, 3 major dietary patterns- prudent dietary pattern, combination dietary pattern and western dietary pattern were identified. Fasting plasma/serum of both cases and controls were analyzed for homocysteine, folate, vitamin B12, blood Pb, ferritin, cholesterol, LDL-cholesterol, HDL-cholesterol and triglycerides. ANOVA and conditional logistic regression were used to predict the association of dietary patterns with AMI. Results: Consumption of prudent diet, characterized by high consumption of legumes, vegetables, wheat, chicken and fruits, is protective against the risk of premature AMI. Moderate to high consumption of combination diet, characterized by high intake of eggs, fish, fruits, juices and coffee was associated with decreased risk of AMI. No association was observed between western diet, characterized by high intake of meat, fish and tea with milk and risk of AMI. Conclusions: Consumption of a prudent dietary pattern and a combination dietary pattern is protective against the risk of AMI in a Pakistani population. PMID:26649016

  11. Field Efficacy of New Larvicide Products for Control of Multi-Resistant Aedes aegypti Populations in Martinique (French West Indies)

    PubMed Central

    Marcombe, Sébastien; Darriet, Frédéric; Agnew, Philip; Etienne, Manuel; Yp-Tcha, Marie-Michelle; Yébakima, André; Corbel, Vincent

    2011-01-01

    World-wide dengue vector control is hampered by the spread of insecticide resistance in Aedes aegypti. We report the resistance status of a wild Ae. aegypti population from Martinique (Vauclin) to conventional larvicides (Bacillus thuringiensis var israeliensis [Bti] and temephos) and potential alternatives (spinosad, diflubenzuron, and pyriproxyfen). The efficacy and residual activity of these insecticides were evaluated under simulated and field conditions. The Vauclin strain exhibited a high level of resistance to temephos, a tolerance to insect growth regulators, and full susceptibility to spinosad and Bti. In simulated trials, pyriproxyfen and Bti showed long residual activities in permanent breeding containers (28 and 37 weeks), whereas under field conditions they failed to curtail Ae. aegypti populations after four weeks. Conversely, diflubenzuron and spinosad showed a residual efficacy of 16 weeks, suggesting that these chemicals may be promising alternatives to Bti and temephos for controlling insecticide-resistant Ae. aegypti populations. PMID:21212213

  12. Field efficacy of new larvicide products for control of multi-resistant Aedes aegypti populations in Martinique (French West Indies).

    PubMed

    Marcombe, Sébastien; Darriet, Frédéric; Agnew, Philip; Etienne, Manuel; Yp-Tcha, Marie-Michelle; Yébakima, André; Corbel, Vincent

    2011-01-01

    World-wide dengue vector control is hampered by the spread of insecticide resistance in Aedes aegypti. We report the resistance status of a wild Ae. aegypti population from Martinique (Vauclin) to conventional larvicides (Bacillus thuringiensis var israeliensis [Bti] and temephos) and potential alternatives (spinosad, diflubenzuron, and pyriproxyfen). The efficacy and residual activity of these insecticides were evaluated under simulated and field conditions. The Vauclin strain exhibited a high level of resistance to temephos, a tolerance to insect growth regulators, and full susceptibility to spinosad and Bti. In simulated trials, pyriproxyfen and Bti showed long residual activities in permanent breeding containers (28 and 37 weeks), whereas under field conditions they failed to curtail Ae. aegypti populations after four weeks. Conversely, diflubenzuron and spinosad showed a residual efficacy of 16 weeks, suggesting that these chemicals may be promising alternatives to Bti and temephos for controlling insecticide-resistant Ae. aegypti populations.

  13. Continuous Effector CD8(+) T Cell Production in a Controlled Persistent Infection Is Sustained by a Proliferative Intermediate Population.

    PubMed

    Chu, H Hamlet; Chan, Shiao-Wei; Gosling, John Paul; Blanchard, Nicolas; Tsitsiklis, Alexandra; Lythe, Grant; Shastri, Nilabh; Molina-París, Carmen; Robey, Ellen A

    2016-07-19

    Highly functional CD8(+) effector T (Teff) cells can persist in large numbers during controlled persistent infections, as exemplified by rare HIV-infected individuals who control the virus. Here we examined the cellular mechanisms that maintain ongoing T effector responses using a mouse model for persistent Toxoplasma gondii infection. In mice expressing the protective MHC-I molecule, H-2L(d), a dominant T effector response against a single parasite antigen was maintained without a contraction phase, correlating with ongoing presentation of the dominant antigen. Large numbers of short-lived Teff cells were continuously produced via a proliferative, antigen-dependent intermediate (Tint) population with a memory-effector hybrid phenotype. During an acute, resolved infection, decreasing antigen load correlated with a sharp drop in the Tint cell population and subsequent loss of the ongoing effector response. Vaccination approaches aimed at the development of Tint populations might prove effective against pathogens that lead to chronic infection. PMID:27421704

  14. Control for Population Structure and Relatedness for Binary Traits in Genetic Association Studies via Logistic Mixed Models

    PubMed Central

    Chen, Han; Wang, Chaolong; Conomos, Matthew P.; Stilp, Adrienne M.; Li, Zilin; Sofer, Tamar; Szpiro, Adam A.; Chen, Wei; Brehm, John M.; Celedón, Juan C.; Redline, Susan; Papanicolaou, George J.; Thornton, Timothy A.; Laurie, Cathy C.; Rice, Kenneth; Lin, Xihong

    2016-01-01

    Linear mixed models (LMMs) are widely used in genome-wide association studies (GWASs) to account for population structure and relatedness, for both continuous and binary traits. Motivated by the failure of LMMs to control type I errors in a GWAS of asthma, a binary trait, we show that LMMs are generally inappropriate for analyzing binary traits when population stratification leads to violation of the LMM’s constant-residual variance assumption. To overcome this problem, we develop a computationally efficient logistic mixed model approach for genome-wide analysis of binary traits, the generalized linear mixed model association test (GMMAT). This approach fits a logistic mixed model once per GWAS and performs score tests under the null hypothesis of no association between a binary trait and individual genetic variants. We show in simulation studies and real data analysis that GMMAT effectively controls for population structure and relatedness when analyzing binary traits in a wide variety of study designs. PMID:27018471

  15. Dietary Pattern and Risk of Hodgkin Lymphoma in a Population-Based Case-Control Study

    PubMed Central

    Epstein, Mara M.; Chang, Ellen T.; Zhang, Yawei; Fung, Teresa T.; Batista, Julie L.; Ambinder, Richard F.; Zheng, Tongzhang; Mueller, Nancy E.; Birmann, Brenda M.

    2015-01-01

    Classic Hodgkin lymphoma (cHL) has few known modifiable risk factors, and the relationship between diet and cHL risk is unclear. We performed the first investigation of an association between dietary pattern and cHL risk in 435 cHL cases and 563 population-based controls from Massachusetts and Connecticut (1997–2000) who completed baseline diet questionnaires. We identified 4 major dietary patterns (“vegetable,” “high meat,” “fruit/low-fat dairy,” “desserts/sweets”) using principal components analysis. We computed multivariable odds ratios and 95% confidence intervals for associations of dietary pattern score (quartiles) with younger-adult (age <50 years), older-adult (age ≥50 years), and overall cHL risk. Secondary analyses examined associations by histological subtype and tumor Epstein-Barr virus (EBV) status. A diet high in desserts/sweets was associated with younger-adult (odds ratio(quartile 4 vs. quartile 1) = 1.60, 95% confidence interval: 1.05, 2.45; Ptrend = 0.008) and EBV-negative, younger-adult (odds ratio = 2.11, 95% confidence interval: 1.31, 3.41; Ptrend = 0.007) cHL risk. A high meat diet was associated with older-adult (odds ratio = 3.34, 95% confidence interval: 1.02, 10.91; Ptrend = 0.04) and EBV-negative, older-adult (odds ratio = 4.64, 95% confidence interval: 1.03, 20.86; Ptrend = 0.04) cHL risk. Other dietary patterns were not clearly associated with cHL. We report the first evidence for a role of dietary pattern in cHL etiology. Diets featuring high intake of meat or desserts and sweets may increase cHL risk. PMID:26182945

  16. The toxin and antidote puzzle: new ways to control insect pest populations through manipulating inheritance.

    PubMed

    Marshall, John M

    2011-01-01

    Insects carry out essential ecological functions, such as pollination, but also cause extensive damage to agricultural crops, and transmit human diseases such as malaria and dengue fever. Advances in insect transgenesis are making it increasingly feasible to engineer genes conferring desirable phenotypes, and gene drive systems are required to spread these genes into wild populations. Medea provides one solution, being able to spread into a population from very low initial frequencies through the action of a maternally-expressed toxin linked to a zygotically-expressed antidote. Several other toxin-antidote combinations are imaginable that distort the offspring ratio in favor of a desired transgene, or drive the population towards an all-male crash. We explore two such systems--Semele, which is capable of spreading a desired transgene into an isolated population in a confined manner; and Merea, which is capable of inducing a local population crash when located on the Z chromosome of a Lepidopteron pest.

  17. Mitigating amphibian disease: strategies to maintain wild populations and control chytridiomycosis

    USGS Publications Warehouse

    Woodhams, Douglas C.; Bosch, Jaime; Briggs, Cheryl J.; Cashins, Scott; Davis, Leyla R.; Lauer, Antje; Muths, Erin L.; Puschendorf, Robert; Schmidt, Benedikt R.; Sheafor, Brandon; Voyles, Jamie

    2011-01-01

    Because sustainable conservation of amphibians in nature is dependent on long-term population persistence and co-evolution with potentially lethal pathogens, we suggest that disease mitigation not focus exclusively on the elimination or containment of the pathogen, or on the captive breeding of amphibian hosts. Rather, successful disease mitigation must be context specific with epidemiologically informed strategies to manage already infected populations by decreasing pathogenicity and host susceptibility. We propose population level treatments based on three steps: first, identify mechanisms of disease suppression; second, parameterize epizootiological models of disease and population dynamics for testing under semi-natural conditions; and third, begin a process of adaptive management in field trials with natural populations.

  18. Restricted random labeling: testing for between-group interaction after controlling for joint population and within-group spatial structure

    NASA Astrophysics Data System (ADS)

    Kronenfeld, Barry J.; Leslie, Timothy F.

    2015-01-01

    Statistical measures of spatial interaction between multiple types of entities are commonly assessed against a null model of either toroidal shift (TS), which controls for spatial structure of individual subpopulations, or random labeling (RL), which controls for spatial structure of the joint population. Neither null model controls for both types of spatial structure simultaneously, although this may sometimes be desirable when more than two subpopulations are present. To address this, we propose a flexible framework for specifying null models that we refer to as restricted random labeling (rRL). Under rRL, a specified subset of individuals is restricted and other individuals are randomly relabeled. Within this framework, two specific null models are proposed for pairwise analysis within populations consisting of three or more subpopulations, to simultaneously control for spatial structure in the joint population and one or the other of the two subpopulations being analyzed. Formulas are presented for calculating expected nearest neighbor counts and co-location quotients within the proposed framework. Differences between TS, RL and rRL are illustrated by application to six types of generating processes in a simulation study, and to empirical datasets of tree species in a forest and crime locations in an urban setting. These examples show that rRL null models are typically stricter than either TS or RL, which often detect "interactions" that are an expected consequence either of the joint population pattern or of individual subpopulation patterns.

  19. Population pharmacokinetic modeling of glibenclamide in poorly controlled South African type 2 diabetic subjects

    PubMed Central

    Rambiritch, Virendra; Naidoo, Poobalan; Maharaj, Breminand; Pillai, Goonaseelan

    2016-01-01

    Aim The aim of this study was to describe the pharmacokinetics (PK) of glibenclamide in poorly controlled South African type 2 diabetic subjects using noncompartmental and model-based methods. Methods A total of 24 subjects with type 2 diabetes were administered increasing doses (0 mg/d, 2.5 mg/d, 5 mg/d, 10 mg/d, and 20 mg/d) of glibenclamide daily at 2-week intervals. Plasma glibenclamide, glucose, and insulin determinations were performed. Blood sampling times were 0 minute, 30 minutes, 60 minutes, 90 minutes, and 120 minutes (post breakfast sampling) and 240 minutes, 270 minutes, 300 minutes, 330 minutes, 360 minutes, and 420 minutes (post lunch sampling) on days 14, 28, 42, 56, and 70 for doses of 0 mg, 2.5 mg, 5.0 mg, 10 mg, and 20 mg, respectively. Blood sampling was performed after the steady state was reached. A total of 24 individuals in the data set contributed to a total of 841 observation records. The PK was analyzed using noncompartmental analysis methods, which were implemented in WinNonLin®, and population PK analysis using NONMEM®. Glibenclamide concentration data were log transformed prior to fitting. Results A two-compartmental disposition model was selected after evaluating one-, two-, and three-compartmental models to describe the time course of glibenclamide plasma concentration data. The one-compartment model adequately described the data; however, the two-compartment model provided a better fit. The three-compartment model failed to achieve successful convergence. A more complex model, to account for enterohepatic recirculation that was observed in the data, was unsuccessful. Conclusion In South African diabetic subjects, glibenclamide demonstrates linear PK and was best described by a two-compartmental model. Except for the absorption rate constant, the other PK parameters reported in this study are comparable to those reported in the scientific literature. The study is limited by the small study sample size and inclusion of poorly

  20. Dominance of Deleterious Alleles Controls the Response to a Population Bottleneck.

    PubMed

    Balick, Daniel J; Do, Ron; Cassa, Christopher A; Reich, David; Sunyaev, Shamil R

    2015-08-01

    Population bottlenecks followed by re-expansions have been common throughout history of many populations. The response of alleles under selection to such demographic perturbations has been a subject of great interest in population genetics. On the basis of theoretical analysis and computer simulations, we suggest that this response qualitatively depends on dominance. The number of dominant or additive deleterious alleles per haploid genome is expected to be slightly increased following the bottleneck and re-expansion. In contrast, the number of completely or partially recessive alleles should be sharply reduced. Changes of population size expose differences between recessive and additive selection, potentially providing insight into the prevalence of dominance in natural populations. Specifically, we use a simple statistic, [Formula: see text], where xi represents the derived allele frequency, to compare the number of mutations in different populations, and detail its functional dependence on the strength of selection and the intensity of the population bottleneck. We also provide empirical evidence showing that gene sets associated with autosomal recessive disease in humans may have a BR indicative of recessive selection. Together, these theoretical predictions and empirical observations show that complex demographic history may facilitate rather than impede inference of parameters of natural selection. PMID:26317225

  1. Dominance of Deleterious Alleles Controls the Response to a Population Bottleneck

    PubMed Central

    Balick, Daniel J.; Do, Ron; Cassa, Christopher A.; Reich, David; Sunyaev, Shamil R.

    2015-01-01

    Population bottlenecks followed by re-expansions have been common throughout history of many populations. The response of alleles under selection to such demographic perturbations has been a subject of great interest in population genetics. On the basis of theoretical analysis and computer simulations, we suggest that this response qualitatively depends on dominance. The number of dominant or additive deleterious alleles per haploid genome is expected to be slightly increased following the bottleneck and re-expansion. In contrast, the number of completely or partially recessive alleles should be sharply reduced. Changes of population size expose differences between recessive and additive selection, potentially providing insight into the prevalence of dominance in natural populations. Specifically, we use a simple statistic, BR≡∑xipop1/∑xjpop2, where x i represents the derived allele frequency, to compare the number of mutations in different populations, and detail its functional dependence on the strength of selection and the intensity of the population bottleneck. We also provide empirical evidence showing that gene sets associated with autosomal recessive disease in humans may have a B R indicative of recessive selection. Together, these theoretical predictions and empirical observations show that complex demographic history may facilitate rather than impede inference of parameters of natural selection. PMID:26317225

  2. Substrate-controlled succession of marine bacterioplankton populations induced by a phytoplankton bloom.

    PubMed

    Teeling, Hanno; Fuchs, Bernhard M; Becher, Dörte; Klockow, Christine; Gardebrecht, Antje; Bennke, Christin M; Kassabgy, Mariette; Huang, Sixing; Mann, Alexander J; Waldmann, Jost; Weber, Marc; Klindworth, Anna; Otto, Andreas; Lange, Jana; Bernhardt, Jörg; Reinsch, Christine; Hecker, Michael; Peplies, Jörg; Bockelmann, Frank D; Callies, Ulrich; Gerdts, Gunnar; Wichels, Antje; Wiltshire, Karen H; Glöckner, Frank Oliver; Schweder, Thomas; Amann, Rudolf

    2012-05-01

    Phytoplankton blooms characterize temperate ocean margin zones in spring. We investigated the bacterioplankton response to a diatom bloom in the North Sea and observed a dynamic succession of populations at genus-level resolution. Taxonomically distinct expressions of carbohydrate-active enzymes (transporters; in particular, TonB-dependent transporters) and phosphate acquisition strategies were found, indicating that distinct populations of Bacteroidetes, Gammaproteobacteria, and Alphaproteobacteria are specialized for successive decomposition of algal-derived organic matter. Our results suggest that algal substrate availability provided a series of ecological niches in which specialized populations could bloom. This reveals how planktonic species, despite their seemingly homogeneous habitat, can evade extinction by direct competition. PMID:22556258

  3. Acute Appendicitis Is Associated with Peptic Ulcers: A Population-based Study.

    PubMed

    Tsai, Ming-Chieh; Kao, Li-Ting; Lin, Herng-Ching; Chung, Shiu-Dong; Lee, Cha-Ze

    2015-12-08

    Despite some studies having indicated a possible association between appendicitis and duodenal ulcers, this association was mainly based on regional samples or limited clinician experiences, and as such, did not permit unequivocal conclusions. In this case-control study, we examined the association of acute appendicitis with peptic ulcers using a population-based database. We included 3574 patients with acute appendicitis as cases and 3574 sex- and age-matched controls. A Chi-squared test showed that there was a significant difference in the prevalences of prior peptic ulcers between cases and controls (21.7% vs. 16.8%, p < 0.001). The adjusted odds ratio (OR) of prior peptic ulcers for cases was 1.40 (95% confidence interval [CI]: 1.24~1.54, p < 0.001) compared to controls. The results further revealed that younger groups demonstrated higher ORs for prior peptic ulcers among cases than controls. In particular, the adjusted OR for cases < 30 years old was as high as 1.65 (95% CI = 1.25~2.19; p < 0.001) compared to controls. However, we failed to observe an association of acute appendicitis with peptic ulcers in the ≥ 60-year age group (OR = 1.19, 95% CI = 0.93~1.52). We concluded that there is an association between acute appendicitis and a previous diagnosis of peptic ulcers.

  4. Alternate scenarios for population control in Pakistan: the issue of contraceptive method mix.

    PubMed

    Ahmed, T; Ali, S M

    1992-01-01

    The authors review Pakistan's population program, with a focus on the ideal mix of contraceptive methods needed to slow population growth. "Our objective in this exercise is to estimate the extent of services required to achieve a certain level of the Contraceptive Prevalence Rate (CPR) necessary to bring fertility down to a level desired by women." Comparison is made between single- and multiple-method approaches.

  5. Predators with multiple ontogenetic niche shifts have limited potential for population growth and top-down control of their prey.

    PubMed

    van Leeuwen, Anieke; Huss, Magnus; Gårdmark, Anna; Casini, Michele; Vitale, Francesca; Hjelm, Joakim; Persson, Lennart; de Roos, André M

    2013-07-01

    Catastrophic collapses of top predators have revealed trophic cascades and community structuring by top-down control. When populations fail to recover after a collapse, this may indicate alternative stable states in the system. Overfishing has caused several of the most compelling cases of these dynamics, and in particular Atlantic cod stocks exemplify such lack of recovery. Often, competition between prey species and juvenile predators is hypothesized to explain the lack of recovery of predator populations. The predator is then considered to compete with its prey for one resource when small and to subsequently shift to piscivory. Yet predator life history is often more complex than that, including multiple ontogenetic diet shifts. Here we show that no alternative stable states occur when predators in an intermediate life stage feed on an additional resource (exclusive to the predator) before switching to piscivory, because predation and competition between prey and predator do not simultaneously structure community dynamics. We find top-down control by the predator only when there is no feedback from predator foraging on the additional resource. Otherwise, the predator population dynamics are governed by a bottleneck in individual growth occurring in the intermediate life stage. Therefore, additional resources for predators may be beneficial or detrimental for predator population growth and strongly influence the potential for top-down community control. PMID:23778226

  6. Population dynamics in controlled unsteady-state systems: An application to the degradation of glyphosate in a sequencing batch reactor

    SciTech Connect

    Devarakonda, M.S.

    1988-01-01

    Control over population dynamics and organism selection in a biological waste treatment system provides an effective means of engineering process efficiency. Examples of applications of organism selection include control of filamentous organisms, biological nutrient removal, industrial waste treatment requiring the removal of specific substrates, and hazardous waste treatment. Inherently, full scale biological waste treatment systems are unsteady state systems due to the variations in the waste streams and mass flow rates of the substrates. Some systems, however, have the capacity to impose controlled selective pressures on the biological population by means of their operation. An example of such a system is the Sequencing Batch Reactor (SBR) which was the experimental system utilized in this research work. The concepts of organism selection were studied in detail for the biodegradation of a herbicide waste stream, with glyphosate as the target compound. The SBR provided a reactor configuration capable of exerting the necessary selective pressures to select and enrich for a glyphosate degrading population. Based on results for bench scale SBRs, a hypothesis was developed to explain population dynamics in glyphosate degrading systems.

  7. Predators with multiple ontogenetic niche shifts have limited potential for population growth and top-down control of their prey.

    PubMed

    van Leeuwen, Anieke; Huss, Magnus; Gårdmark, Anna; Casini, Michele; Vitale, Francesca; Hjelm, Joakim; Persson, Lennart; de Roos, André M

    2013-07-01

    Catastrophic collapses of top predators have revealed trophic cascades and community structuring by top-down control. When populations fail to recover after a collapse, this may indicate alternative stable states in the system. Overfishing has caused several of the most compelling cases of these dynamics, and in particular Atlantic cod stocks exemplify such lack of recovery. Often, competition between prey species and juvenile predators is hypothesized to explain the lack of recovery of predator populations. The predator is then considered to compete with its prey for one resource when small and to subsequently shift to piscivory. Yet predator life history is often more complex than that, including multiple ontogenetic diet shifts. Here we show that no alternative stable states occur when predators in an intermediate life stage feed on an additional resource (exclusive to the predator) before switching to piscivory, because predation and competition between prey and predator do not simultaneously structure community dynamics. We find top-down control by the predator only when there is no feedback from predator foraging on the additional resource. Otherwise, the predator population dynamics are governed by a bottleneck in individual growth occurring in the intermediate life stage. Therefore, additional resources for predators may be beneficial or detrimental for predator population growth and strongly influence the potential for top-down community control.

  8. Training leaders from priority populations to implement social norm changes in tobacco control: lessons from the LAAMPP Institute.

    PubMed

    Lew, Rod; Martinez, Jaime; Soto, Claradina; Baezconde-Garbanati, Lourdes

    2011-11-01

    The development of leadership in tobacco control has been crucial in the fight against the number one most preventable cause of death and disease worldwide. Yet today, little scientific evidence exists regarding its actual impact, particularly among priority populations. This article describes the impact of the Leadership and Advocacy Institute to Advance Minnesota's Parity for Priority Populations (LAAMPP Institute), a major tobacco control leadership program for five priority populations: African/African Americans, American Indians, Asian Americans, Chicano/Latinos, and lesbian, gay, bisexual, transgender communities in Minnesota. The LAAMPP Institute, a year-long institute with 17 days of training, focused on the core competencies of advocacy, collaboration, cultural or community competency, facilitation, and tobacco control. A logic model helped to guide and frame the institute's efforts. The LAAMPP Institute has been effective in increasing fellows' capacity to do advocacy, which in turn has led to increased involvement in implementing social norm-change activities. Leadership development can provide a solid foundation for training leaders and a catalyst for mobilizing key advocates and priority population communities toward the implementation and sustainment of social norm or policy changes.

  9. Hospital Recorded Morbidity and Breast Cancer Incidence: A Nationwide Population-Based Case-Control Study

    PubMed Central

    Ording, Anne Gulbech; Garne, Jens Peter; Nyström, Petra Mariann Witt; Cronin-Fenton, Deirdre; Tarp, Maja; Sørensen, Henrik Toft; Lash, Timothy L.

    2012-01-01

    Introduction Chronic diseases and their complications may increase breast cancer risk through known or still unknown mechanisms, or by shared causes. The association between morbidities and breast cancer risk has not been studied in depth. Methods Data on all Danish women aged 45 to 85 years, diagnosed with breast cancer between 1994 and 2008 and data on preceding morbidities were retrieved from nationwide medical registries. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using conditional logistic regression associating the Charlson comorbidity score (measured using both the original and an updated Charlson Comorbidity Index (CCI)) with incident breast cancer. Furthermore, we estimated associations between 202 morbidity categories and incident breast cancer, adjusting for multiple comparisons using empirical Bayes (EB) methods. Results The study included 46,324 cases and 463,240 population controls. Increasing CCI score, up to a score of six, was associated with slightly increased breast cancer risk. Among the Charlson diseases, preceding moderate to severe renal disease (OR = 1.25, 95% CI: 1.06, 1.48), any tumor (OR = 1.17, 95% CI: 1.10, 1.25), moderate to severe liver disease (OR = 1.86, 95% CI: 1.32, 2.62), and metastatic solid tumors (OR = 1.49, 95% CI: 1.17, 1.89), were most strongly associated with subsequent breast cancer. Preceding myocardial infarction (OR = 0.89, 95% CI: 0.81, 0.99), connective tissue disease (OR = 0.87, 95% CI: 0.80, 0.94), and ulcer disease (OR = 0.91, 95% CI: 0.83, 0.99) were most strongly inversely associated with subsequent breast cancer. A history of breast disorders was associated with breast cancer after EB adjustment. Anemias were inversely associated with breast cancer, but the association was near null after EB adjustment. Conclusions There was no substantial association between morbidity measured with the CCI and breast cancer risk. PMID:23094045

  10. Disease Risk Estimation by Combining Case–Control Data with Aggregated Information on the Population at Risk

    PubMed Central

    Chang, Xiaohui; Waagepetersen, Rasmus; Yu, Herbert; Ma, Xiaomei; Holford, Theodore R.; Wang, Rong; Guan, Yongtao

    2016-01-01

    Summary We propose a novel statistical framework by supplementing case–control data with summary statistics on the population at risk for a subset of risk factors. Our approach is to first form two unbiased estimating equations, one based on the case–control data and the other on both the case data and the summary statistics, and then optimally combine them to derive another estimating equation to be used for the estimation. The proposed method is computationally simple and more efficient than standard approaches based on case–control data alone. We also establish asymptotic properties of the resulting estimator, and investigate its finite-sample performance through simulation. As a substantive application, we apply the proposed method to investigate risk factors for endometrial cancer, by using data from a recently completed population-based case–control study and summary statistics from the Behavioral Risk Factor Surveillance System, the Population Estimates Program of the US Census Bureau, and the Connecticut Department of Transportation. PMID:25351292

  11. Association of genetic polymorphisms with chronic obstructive pulmonary disease in the Chinese Han population: a case–control study

    PubMed Central

    2012-01-01

    Background Chronic obstructive pulmonary disease (COPD) is influenced by both environmental and genetic factors. Few gene studies of the Chinese population have focused on COPD. We investigated candidate genes associated with susceptibility to COPD in the Chinese Han population. Methods A total of 331 COPD patients and 213 control subjects were recruited for this study. Nighty-seven single-nucleotide polymorphisms (SNPs) of 46 genes were selected for genotyping. Genotypes were determined using multiplex polymerase chain reaction (PCR). Results Significant differences between patients and healthy controls were observed in the allele frequencies of seven SNPs: rs1205 C, rs2353397 C, rs20541 T, rs2070600 G, rs10947233 G, rs1800629 G, and rs2241712 A. After Bonferroni correction, rs2353397 C was most strongly associated with susceptibility to COPD. Haplotype analysis showed that the frequencies of the GC, GT haplotypes of rs2241718 (TGF-β1 gene), and rs6957 (CDC97 gene) were significantly higher in the control group than in the COPD case group (p=1.88×10-9); the frequencies of the TT haplotype of rs1205 and rs2808630 (CRP gene) were significantly higher in the control group (p=0.0377). Conclusion Our study suggests some genetic variants associated with the susceptibility of COPD in the Chinese Han population. PMID:23267696

  12. Sustained Reduction of the Dengue Vector Population Resulting from an Integrated Control Strategy Applied in Two Brazilian Cities

    PubMed Central

    Regis, Lêda N.; Acioli, Ridelane Veiga; Silveira, José Constantino; Melo-Santos, Maria Alice Varjal; Souza, Wayner Vieira; Ribeiro, Cândida M. Nogueira.; da Silva, Juliana C. Serafim.; Monteiro, Antonio Miguel Vieira; Oliveira, Cláudia M. F.; Barbosa, Rosângela M. R.; Braga, Cynthia; Rodrigues, Marco Aurélio Benedetti; Silva, Marilú Gomes N. M.; Ribeiro Jr., Paulo Justiniano; Bonat, Wagner Hugo; de Castro Medeiros, Liliam César; Carvalho, Marilia Sa; Furtado, André Freire

    2013-01-01

    Aedes aegypti has developed evolution-driven adaptations for surviving in the domestic human habitat. Several trap models have been designed considering these strategies and tested for monitoring this efficient vector of Dengue. Here, we report a real-scale evaluation of a system for monitoring and controlling mosquito populations based on egg sampling coupled with geographic information systems technology. The SMCP-Aedes, a system based on open technology and open data standards, was set up from March/2008 to October/2011 as a pilot trial in two sites of Pernambuco -Brazil: Ipojuca (10,000 residents) and Santa Cruz (83,000), in a joint effort of health authorities and staff, and a network of scientists providing scientific support. A widespread infestation by Aedes was found in both sites in 2008–2009, with 96.8%–100% trap positivity. Egg densities were markedly higher in SCC than in Ipojuca. A 90% decrease in egg density was recorded in SCC after two years of sustained control pressure imposed by suppression of >7,500,000 eggs and >3,200 adults, plus larval control by adding fishes to cisterns. In Ipojuca, 1.1 million mosquito eggs were suppressed and a 77% reduction in egg density was achieved. This study aimed at assessing the applicability of a system using GIS and spatial statistic analysis tools for quantitative assessment of mosquito populations. It also provided useful information on the requirements for reducing well-established mosquito populations. Results from two cities led us to conclude that the success in markedly reducing an Aedes population required the appropriate choice of control measures for sustained mass elimination guided by a user-friendly mosquito surveillance system. The system was able to support interventional decisions and to assess the program’s success. Additionally, it created a stimulating environment for health staff and residents, which had a positive impact on their commitment to the dengue control program. PMID:23844059

  13. Molecular-Level Tuning of Cellular Autonomy Controls the Collective Behaviors of Cell Populations.

    PubMed

    Maire, Théo; Youk, Hyun

    2015-11-25

    A rigorous understanding of how multicellular behaviors arise from the actions of single cells requires quantitative frameworks that bridge the gap between genetic circuits, the arrangement of cells in space, and population-level behaviors. Here, we provide such a framework for a ubiquitous class of multicellular systems-namely, "secrete-and-sense cells" that communicate by secreting and sensing a signaling molecule. By using formal, mathematical arguments and introducing the concept of a phenotype diagram, we show how these cells tune their degrees of autonomous and collective behavior to realize distinct single-cell and population-level phenotypes; these phenomena have biological analogs, such as quorum sensing or paracrine signaling. We also define the "entropy of population," a measurement of the number of arrangements that a population of cells can assume, and demonstrate how a decrease in the entropy of population accompanies the formation of ordered spatial patterns. Our conceptual framework ties together diverse systems, including tissues and microbes, with common principles. PMID:27136241

  14. El Niño controls Holocene rabbit and hare populations in Baja California

    NASA Astrophysics Data System (ADS)

    Hart, Isaac A.; Broughton, Jack M.; Gruhn, Ruth

    2015-07-01

    The El Niño/Southern Oscillation (ENSO) is a major source of climatic variation worldwide, with significant impacts on modern human and animal populations. However, few detailed records exist on the long-term effects of ENSO on prehistoric vertebrate populations. Here we examine how lagomorph (rabbit and hare) deposition rate, population age structure and taxonomic composition from Abrigo de los Escorpiones, a well-dated, trans-Holocene vertebrate fauna from northern Baja California, Mexico, vary as a function of the frequency of wet El Niño events and eastern Pacific sea-surface temperatures (SSTs) derived from eastern Pacific geological records. Faunal indices vary significantly in response to El Niño-based precipitation and SST, with substantial moisture-driven variability in the middle and late Holocene. The late Holocene moisture pulse is coincident with previously documented changes in the population dynamics of other vertebrates, including humans. As the frequency and intensity of ENSO is anticipated to vary in the future, these results have important implications for change in future vertebrate populations.

  15. Differentiation of African Components of Ancestry to Stratify Groups in a Case–Control Study of a Brazilian Urban Population

    PubMed Central

    Hirata, Mario H.; Luchessi, Andre D.; Genvigir, Fabiana D.V.; Cerda, Alvaro; Rodrigues, Alice C.; Willrich, Maria A.V.; Arazi, Simone S.; Dorea, Egidio L.; Bernik, Marcia M.S.; Faludi, Andre A.; Bertolami, Marcelo C.; Santos, Carla; Carracedo, Ángel; Salas, Antonio; Freire, Ana; Lareu, Maria Victoria; Phillips, Christopher; Porras-Hurtado, Liliana; Fondevila, Manuel; Hirata, Rosario D.C.

    2012-01-01

    Background: Balancing the subject composition of case and control groups to create homogenous ancestries between each group is essential for medical association studies. Methods: We explored the applicability of single-tube 34-plex ancestry informative markers (AIM) single nucleotide polymorphisms (SNPs) to estimate the African Component of Ancestry (ACA) to design a future case–control association study of a Brazilian urban sample. Results: One hundred eighty individuals (107 case group; 73 control group) self-described as white, brown-intermediate or black were selected. The proportions of the relative contribution of a variable number of ancestral population components were similar between case and control groups. Moreover, the case and control groups demonstrated similar distributions for ACA <0.25 and >0.50 categories. Notably a high number of outlier values (23 samples) were observed among individuals with ACA <0.25. These individuals presented a high probability of Native American and East Asian ancestral components; however, no individuals originally giving these self-described ancestries were observed in this study. Conclusions: The strategy proposed for the assessment of ancestry and adjustment of case and control groups for an association study is an important step for the proper construction of the study, particularly when subjects are taken from a complex urban population. This can be achieved using a straight forward multiplexed AIM-SNPs assay of highly discriminatory ancestry markers. PMID:22288895

  16. Comprehensive approach for hypertension control in low-income populations: rationale and study design for the hypertension control program in Argentina.

    PubMed

    Mills, Katherine T; Rubinstein, Adolfo; Irazola, Vilma; Chen, Jing; Beratarrechea, Andrea; Poggio, Rosana; Dolan, Jacquelyn; Augustovski, Federico; Shi, Lizheng; Krousel-Wood, Marie; Bazzano, Lydia A; He, Jiang

    2014-08-01

    Although the efficacy and effectiveness of lifestyle modifications and antihypertensive pharmaceutical treatment for the prevention and control of hypertension and concomitant cardiovascular disease have been demonstrated in randomized controlled trials, this scientific knowledge has not been fully applied in the general population, especially in low-income communities. This article summarizes interventions to improve hypertension management and describes the rationale and study design for a cluster randomized trial testing whether a comprehensive intervention program within a national public primary care system will improve hypertension control among uninsured hypertensive men and women and their families. We will recruit 1,890 adults from 18 clinics within a public primary care network in Argentina. Clinic patients with uncontrolled hypertension, their spouses and hypertensive family members will be enrolled. The comprehensive intervention program targets the primary care system through health care provider education, a home-based intervention among patients and their families (home delivery of antihypertensive medication, self-monitoring of blood pressure [BP], health education for medication adherence and lifestyle modification) conducted by community health workers and a mobile health intervention. The primary outcome is net change in systolic BP from baseline to month 18 between intervention and control groups among hypertensive study participants. The secondary outcomes are net change in diastolic BP, BP control and cost-effectiveness of the intervention. This study will generate urgently needed data on effective, practical and sustainable intervention programs aimed at controlling hypertension and concomitant cardiovascular disease in underserved populations in low- and middle-income countries.

  17. Comprehensive approach for hypertension control in low-income populations: rationale and study design for the hypertension control program in Argentina.

    PubMed

    Mills, Katherine T; Rubinstein, Adolfo; Irazola, Vilma; Chen, Jing; Beratarrechea, Andrea; Poggio, Rosana; Dolan, Jacquelyn; Augustovski, Federico; Shi, Lizheng; Krousel-Wood, Marie; Bazzano, Lydia A; He, Jiang

    2014-08-01

    Although the efficacy and effectiveness of lifestyle modifications and antihypertensive pharmaceutical treatment for the prevention and control of hypertension and concomitant cardiovascular disease have been demonstrated in randomized controlled trials, this scientific knowledge has not been fully applied in the general population, especially in low-income communities. This article summarizes interventions to improve hypertension management and describes the rationale and study design for a cluster randomized trial testing whether a comprehensive intervention program within a national public primary care system will improve hypertension control among uninsured hypertensive men and women and their families. We will recruit 1,890 adults from 18 clinics within a public primary care network in Argentina. Clinic patients with uncontrolled hypertension, their spouses and hypertensive family members will be enrolled. The comprehensive intervention program targets the primary care system through health care provider education, a home-based intervention among patients and their families (home delivery of antihypertensive medication, self-monitoring of blood pressure [BP], health education for medication adherence and lifestyle modification) conducted by community health workers and a mobile health intervention. The primary outcome is net change in systolic BP from baseline to month 18 between intervention and control groups among hypertensive study participants. The secondary outcomes are net change in diastolic BP, BP control and cost-effectiveness of the intervention. This study will generate urgently needed data on effective, practical and sustainable intervention programs aimed at controlling hypertension and concomitant cardiovascular disease in underserved populations in low- and middle-income countries. PMID:24978148

  18. People of the British Isles: preliminary analysis of genotypes and surnames in a UK-control population

    PubMed Central

    Winney, Bruce; Boumertit, Abdelhamid; Day, Tammy; Davison, Dan; Echeta, Chikodi; Evseeva, Irina; Hutnik, Katarzyna; Leslie, Stephen; Nicodemus, Kristin; Royrvik, Ellen C; Tonks, Susan; Yang, Xiaofeng; Cheshire, James; Longley, Paul; Mateos, Pablo; Groom, Alexandra; Relton, Caroline; Bishop, D Tim; Black, Kathryn; Northwood, Emma; Parkinson, Louise; Frayling, Timothy M; Steele, Anna; Sampson, Julian R; King, Turi; Dixon, Ron; Middleton, Derek; Jennings, Barbara; Bowden, Rory; Donnelly, Peter; Bodmer, Walter

    2012-01-01

    There is a great deal of interest in a fine-scale population structure in the UK, both as a signature of historical immigration events and because of the effect population structure may have on disease association studies. Although population structure appears to have a minor impact on the current generation of genome-wide association studies, it is likely to have a significant part in the next generation of studies designed to search for rare variants. A powerful way of detecting such structure is to control and document carefully the provenance of the samples involved. In this study, we describe the collection of a cohort of rural UK samples (The People of the British Isles), aimed at providing a well-characterised UK-control population that can be used as a resource by the research community, as well as providing a fine-scale genetic information on the British population. So far, some 4000 samples have been collected, the majority of which fit the criteria of coming from a rural area and having all four grandparents from approximately the same area. Analysis of the first 3865 samples that have been geocoded indicates that 75% have a mean distance between grandparental places of birth of 37.3 km, and that about 70% of grandparental places of birth can be classed as rural. Preliminary genotyping of 1057 samples demonstrates the value of these samples for investigating a fine-scale population structure within the UK, and shows how this can be enhanced by the use of surnames. PMID:21829225

  19. Changes in Chondrogenic Progenitor Populations Associated with Aging and Osteoarthritis.

    PubMed

    Brady, Kyla; Dickinson, Sally C; Hollander, Anthony P

    2015-04-01

    Chondrogenic progenitor populations, including mesenchymal stem cells, represent promising cell-based transplantation or tissue engineering therapies for the regeneration of damaged cartilage. Osteoarthritis (OA) predominantly affects the elderly and is a leading cause of disability worldwide. Advancing age is a prominent risk factor that is closely associated with the onset and progression of the disease. Understanding the influence that aging and OA have on chondrogenic progenitor cells is important to determine how these processes affect the cellular mechanisms of the cells and their capacity to differentiate into functional chondrocytes for use in therapeutic applications. Here, we review the effect of age- and OA-related changes on the growth kinetics and differentiation potential of chondrogenic progenitor cell populations. Aging differentially influences the proliferative potential of progenitor cells showing reduced growth rates with increased senescence and apoptotic activity over time, while chondrogenesis appears to be independent of donor age. Cartilage tissue affected by OA shows evidence of progenitor populations with some potential for repair, however reports on the proliferative propensity of mesenchymal stem cells and their chondrogenic potential are contradictory. This is likely attributed to the narrow age ranges of samples assessed and deficits in definitively identifying donors with OA versus healthy patients across a wide scope of advancing ages. Further studies that investigate the mechanistic effects of chondrogenic progenitor populations associated with aging and the progression of OA using clearly defined criteria and age-matched control subject groups are crucial to our understanding of the clinical relevance of these cells for use in cartilage repair therapies. PMID:27340514

  20. Changes in Chondrogenic Progenitor Populations Associated with Aging and Osteoarthritis

    PubMed Central

    Brady, Kyla; Dickinson, Sally C.

    2015-01-01

    Chondrogenic progenitor populations, including mesenchymal stem cells, represent promising cell-based transplantation or tissue engineering therapies for the regeneration of damaged cartilage. Osteoarthritis (OA) predominantly affects the elderly and is a leading cause of disability worldwide. Advancing age is a prominent risk factor that is closely associated with the onset and progression of the disease. Understanding the influence that aging and OA have on chondrogenic progenitor cells is important to determine how these processes affect the cellular mechanisms of the cells and their capacity to differentiate into functional chondrocytes for use in therapeutic applications. Here, we review the effect of age- and OA-related changes on the growth kinetics and differentiation potential of chondrogenic progenitor cell populations. Aging differentially influences the proliferative potential of progenitor cells showing reduced growth rates with increased senescence and apoptotic activity over time, while chondrogenesis appears to be independent of donor age. Cartilage tissue affected by OA shows evidence of progenitor populations with some potential for repair, however reports on the proliferative propensity of mesenchymal stem cells and their chondrogenic potential are contradictory. This is likely attributed to the narrow age ranges of samples assessed and deficits in definitively identifying donors with OA versus healthy patients across a wide scope of advancing ages. Further studies that investigate the mechanistic effects of chondrogenic progenitor populations associated with aging and the progression of OA using clearly defined criteria and age-matched control subject groups are crucial to our understanding of the clinical relevance of these cells for use in cartilage repair therapies. PMID:27340514

  1. Raw garlic consumption as a protective factor for lung cancer, a population-based case-control study in a Chinese population.

    PubMed

    Jin, Zi-Yi; Wu, Ming; Han, Ren-Qiang; Zhang, Xiao-Feng; Wang, Xu-Shan; Liu, Ai-Ming; Zhou, Jin-Yi; Lu, Qing-Yi; Zhang, Zuo-Feng; Zhao, Jin-Kou

    2013-07-01

    Protective effect of garlic on the development of cancer has been reported in the in vitro and in vivo experimental studies; however, few human epidemiologic studies have evaluated the relationship. A population-based case-control study has been conducted in a Chinese population from 2003 to 2010, with the aim to explore the association between raw garlic consumption and lung cancer. Epidemiologic data were collected by face-to-face interviews using a standard questionnaire among 1,424 lung cancer cases and 4,543 healthy controls. Unconditional logistic regression was used to estimate adjusted ORs and their 95% confidence intervals (CI), and to evaluate ratio of ORs (ROR) for multiplicative interactions between raw garlic consumption and other risk factors. After adjusting for potential confounding factors, raw garlic consumption of 2 times or more per week is inversely associated with lung cancer (OR = 0.56; 95% CI, 0.44-0.72) with a monotonic dose-response relationship (Ptrend < 0.001). Furthermore, strong interactions at either additive and/or multiplicative scales were observed between raw garlic consumption and tobacco smoking [synergy index (SI) = 0.70; 95% CI, 0.57-0.85; and ROR = 0.78; 95% CI, 0.67-0.90], as well as high-temperature cooking oil fume (ROR = 0.77; 95% CI, 0.59-1.00). In conclusion, protective association between intake of raw garlic and lung cancer has been observed with a dose-response pattern, suggesting that garlic may potentially serve as a chemopreventive agent for lung cancer. Effective components in garlic in lung cancer chemoprevention warrant further in-depth investigation.

  2. Abnormal Population Responses in the Somatosensory Cortex of Alzheimer’s Disease Model Mice

    PubMed Central

    Maatuf, Yossi; Stern, Edward A.; Slovin, Hamutal

    2016-01-01

    Alzheimer’s disease (AD) is the most common form of dementia. One of the neuropathological hallmarks of AD is the accumulation of amyloid-β plaques. Overexpression of human amyloid precursor protein in transgenic mice induces hippocampal and neocortical amyloid-β accumulation and plaque deposition that increases with age. The impact of these effects on neuronal population responses and network activity in sensory cortex is not well understood. We used Voltage Sensitive Dye Imaging, to investigate at high spatial and temporal resolution, the sensory evoked population responses in the barrel cortex of aged transgenic (Tg) mice and of age-matched non-transgenic littermate controls (Ctrl) mice. We found that a whisker deflection evoked abnormal sensory responses in the barrel cortex of Tg mice. The response amplitude and the spatial spread of the cortical responses were significantly larger in Tg than in Ctrl mice. At the network level, spontaneous activity was less synchronized over cortical space than in Ctrl mice, however synchronization during evoked responses induced by whisker deflection did not differ between the two groups. Thus, the presence of elevated Aβ and plaques may alter population responses and disrupts neural synchronization in large-scale networks, leading to abnormalities in sensory processing. PMID:27079783

  3. A multi-scale study of Orthoptera species richness and human population size controlling for sampling effort

    NASA Astrophysics Data System (ADS)

    Cantarello, Elena; Steck, Claude E.; Fontana, Paolo; Fontaneto, Diego; Marini, Lorenzo; Pautasso, Marco

    2010-03-01

    Recent large-scale studies have shown that biodiversity-rich regions also tend to be densely populated areas. The most obvious explanation is that biodiversity and human beings tend to match the distribution of energy availability, environmental stability and/or habitat heterogeneity. However, the species-people correlation can also be an artefact, as more populated regions could show more species because of a more thorough sampling. Few studies have tested this sampling bias hypothesis. Using a newly collated dataset, we studied whether Orthoptera species richness is related to human population size in Italy’s regions (average area 15,000 km2) and provinces (2,900 km2). As expected, the observed number of species increases significantly with increasing human population size for both grain sizes, although the proportion of variance explained is minimal at the provincial level. However, variations in observed Orthoptera species richness are primarily associated with the available number of records, which is in turn well correlated with human population size (at least at the regional level). Estimated Orthoptera species richness (Chao2 and Jackknife) also increases with human population size both for regions and provinces. Both for regions and provinces, this increase is not significant when controlling for variation in area and number of records. Our study confirms the hypothesis that broad-scale human population-biodiversity correlations can in some cases be artefactual. More systematic sampling of less studied taxa such as invertebrates is necessary to ascertain whether biogeographical patterns persist when sampling effort is kept constant or included in models.

  4. Developing new approaches for detecting and preventing Aedes aegypti population outbreaks: basis for surveillance, alert and control system.

    PubMed

    Regis, Lêda; Monteiro, Antonio Miguel; Melo-Santos, Maria Alice Varjal de; SilveiraJr, José Constantino; Furtado, André Freire; Acioli, Ridelane Veiga; Santos, Gleice Maria; Nakazawa, Mitsue; Carvalho, Marilia Sá; Ribeiro Jr, Paulo Justiniano; Souza, Wayner Vieira de

    2008-02-01

    A new approach to dengue vector surveillance based on permanent egg-collection using a modified ovitrap and Bacillus thuringiensis israelensis(Bti) was evaluated in different urban landscapes in Recife, Northeast Brazil. From April 2004 to April 2005, 13 egg-collection cycles of four weeks were carried out. Geo-referenced ovitraps containing grass infusion, Bti and three paddles were placed at fixed sampling stations distributed over five selected sites. Continuous egg-collections yielded more than four million eggs laid into 464 sentinel-ovitraps over one year. The overall positive ovitrap index was 98.5% (over 5,616 trap observations). The egg density index ranged from 100 to 2,500 eggs per trap-cycle, indicating a wide spread and high density of Aedes aegypti (Diptera: Culicidae) breeding populations in all sites. Fluctuations in population density over time were observed, particularly a marked increase from January on, or later, according to site. Massive egg-collection carried out at one of the sites prevented such a population outbreak. At intra-site level, egg counts made it possible to identify spots where the vector population is consistently concentrated over the time, pinpointing areas that should be considered high priority for control activities. The results indicate that these could be promising strategies for detecting and preventing Ae. aegypti population outbreaks. PMID:18368236

  5. Large fluctuations in the effective population size of the malaria mosquito Anopheles gambiae s.s. during vector control cycle.

    PubMed

    Hodges, Theresa K; Athrey, Giridhar; Deitz, Kevin C; Overgaard, Hans J; Matias, Abrahan; Caccone, Adalgisa; Slotman, Michel A

    2013-12-01

    On Bioko Island, Equatorial Guinea, indoor residual spraying (IRS) has been part of the Bioko Island Malaria Control Project since early 2004. Despite success in reducing childhood infections, areas of high transmission remain on the island. We therefore examined fluctuations in the effective population size (N e ) of the malaria vector Anopheles gambiae in an area of persistent high transmission over two spray rounds. We analyzed data for 13 microsatellite loci from 791 An. gambiae specimens collected at six time points in 2009 and 2010 and reconstructed the demographic history of the population during this period using approximate Bayesian computation (ABC). Our analysis shows that IRS rounds have a large impact on N e , reducing it by 65%-92% from prespray round N e . More importantly, our analysis shows that after 3-5 months, the An. gambiae population rebounded by 2818% compared shortly following the spray round. Our study underscores the importance of adequate spray round frequency to provide continuous suppression of mosquito populations and that increased spray round frequency should substantially improve the efficacy of IRS campaigns. It also demonstrates the ability of ABC to reconstruct a detailed demographic history across only a few tens of generations in a large population.

  6. Large fluctuations in the effective population size of the malaria mosquito Anopheles gambiae s.s. during vector control cycle

    PubMed Central

    Hodges, Theresa K; Athrey, Giridhar; Deitz, Kevin C; Overgaard, Hans J; Matias, Abrahan; Caccone, Adalgisa; Slotman, Michel A

    2013-01-01

    On Bioko Island, Equatorial Guinea, indoor residual spraying (IRS) has been part of the Bioko Island Malaria Control Project since early 2004. Despite success in reducing childhood infections, areas of high transmission remain on the island. We therefore examined fluctuations in the effective population size (Ne) of the malaria vector Anopheles gambiae in an area of persistent high transmission over two spray rounds. We analyzed data for 13 microsatellite loci from 791 An. gambiae specimens collected at six time points in 2009 and 2010 and reconstructed the demographic history of the population during this period using approximate Bayesian computation (ABC). Our analysis shows that IRS rounds have a large impact on Ne, reducing it by 65%–92% from prespray round Ne. More importantly, our analysis shows that after 3–5 months, the An. gambiae population rebounded by 2818% compared shortly following the spray round. Our study underscores the importance of adequate spray round frequency to provide continuous suppression of mosquito populations and that increased spray round frequency should substantially improve the efficacy of IRS campaigns. It also demonstrates the ability of ABC to reconstruct a detailed demographic history across only a few tens of generations in a large population. PMID:24478799

  7. Quantification of rat retinal growth and vascular population changes after single and split doses of proton irradiation: translational study using stereology methods

    NASA Technical Reports Server (NTRS)

    Mao, Xiao W.; Archambeau, John O.; Kubinova, Lucie; Boyle, Soames; Petersen, Georgia; Grove, Roger; Nelson, G. A. (Principal Investigator)

    2003-01-01

    This study quantified architectural and population changes in the rat retinal vasculature after proton irradiation using stereology. A 100 MeV conformal proton beam delivered 8, 14, 20 and 28 Gy as single and split doses to the whole eye. The vascular networks were prepared from retinal digests. Stereological methods were used to obtain the area of the retina and unbiased estimates of microvessel/artery/vein endothelial, pericyte and smooth muscle population, and vessel length. The retinal area increased progressively in the unirradiated, age-matched controls and in the retinas irradiated with 8 and 14 Gy, indicating uniform progressive retinal growth. No growth occurred after 20 and 28 Gy. Regression analysis of total endothelial cell number in all vessels (arteries, veins and capillaries) after irradiation documented a progressive time- and dose-dependent cell loss occurring over 15 to 24 months. The difference from controls was significant (P<0.01) after 28 Gy given in single and split doses and after 20 Gy given as a split dose (P<0.05). Total vessel length in microvessel was significantly shortened at 20 and 28 Gy compared to that of controls (P<0.05). No evident dose recovery was observed in the endothelial populations after split doses. At 10 Gy, the rate of endothelial cell loss, a dose parameter used to characterize the time- and dose-dependent loss of the endothelial population, was doubled.

  8. Fire controls population structure in four dominant tree species in a tropical savanna.

    PubMed

    Lehmann, Caroline E R; Prior, Lynda D; Bowman, David M J S

    2009-09-01

    The persistence of mesic savannas has been theorised as being dependent on disturbances that restrict the number of juveniles growing through the sapling size class to become fire-tolerant trees. We analysed the population structures of four dominant tropical savanna tree species from 30 locations in Kakadu National Park (KNP), northern Australia. We found that across KNP as a whole, the population size structures of these species do not exhibit recruitment bottlenecks. However, individual stands had multimodal size-class distributions and mixtures of tree species consistent with episodic and individualistic recruitment of co-occurring tree species. Using information theory and multimodel inference, we examined the relative importance of fire frequency, stand basal area and elevation difference between a site and permanent water in explaining variations in the proportion of sapling to adult stems in four dominant tree species. This showed that the proportion of the tree population made up of saplings was negatively related to both fire frequencies and stand basal area. Overall, fire frequency has density-dependent effects in the regulation of the transition of saplings to trees in this Australian savanna, due to interactions with stem size, regeneration strategies, growth rates and tree-tree competition. Although stable at the regional scale, the spatiotemporal variability of fire can result in structural and floristic diversity of savanna tree populations. PMID:19629532

  9. Reconsideration of r/K Selection Theory Using Stochastic Control Theory and Nonlinear Structured Population Models.

    PubMed

    Oizumi, Ryo; Kuniya, Toshikazu; Enatsu, Yoichi

    2016-01-01

    Despite the fact that density effects and individual differences in life history are considered to be important for evolution, these factors lead to several difficulties in understanding the evolution of life history, especially when population sizes reach the carrying capacity. r/K selection theory explains what types of life strategies evolve in the presence of density effects and individual differences. However, the relationship between the life schedules of individuals and population size is still unclear, even if the theory can classify life strategies appropriately. To address this issue, we propose a few equations on adaptive life strategies in r/K selection where density effects are absent or present. The equations detail not only the adaptive life history but also the population dynamics. Furthermore, the equations can incorporate temporal individual differences, which are referred to as internal stochasticity. Our framework reveals that maximizing density effects is an evolutionarily stable strategy related to the carrying capacity. A significant consequence of our analysis is that adaptive strategies in both selections maximize an identical function, providing both population growth rate and carrying capacity. We apply our method to an optimal foraging problem in a semelparous species model and demonstrate that the adaptive strategy yields a lower intrinsic growth rate as well as a lower basic reproductive number than those obtained with other strategies. This study proposes that the diversity of life strategies arises due to the effects of density and internal stochasticity. PMID:27336169

  10. Reconsideration of r/K Selection Theory Using Stochastic Control Theory and Nonlinear Structured Population Models

    PubMed Central

    Oizumi, Ryo; Kuniya, Toshikazu; Enatsu, Yoichi

    2016-01-01

    Despite the fact that density effects and individual differences in life history are considered to be important for evolution, these factors lead to several difficulties in understanding the evolution of life history, especially when population sizes reach the carrying capacity. r/K selection theory explains what types of life strategies evolve in the presence of density effects and individual differences. However, the relationship between the life schedules of individuals and population size is still unclear, even if the theory can classify life strategies appropriately. To address this issue, we propose a few equations on adaptive life strategies in r/K selection where density effects are absent or present. The equations detail not only the adaptive life history but also the population dynamics. Furthermore, the equations can incorporate temporal individual differences, which are referred to as internal stochasticity. Our framework reveals that maximizing density effects is an evolutionarily stable strategy related to the carrying capacity. A significant consequence of our analysis is that adaptive strategies in both selections maximize an identical function, providing both population growth rate and carrying capacity. We apply our method to an optimal foraging problem in a semelparous species model and demonstrate that the adaptive strategy yields a lower intrinsic growth rate as well as a lower basic reproductive number than those obtained with other strategies. This study proposes that the diversity of life strategies arises due to the effects of density and internal stochasticity. PMID:27336169

  11. Using global information technology to detect, monitor, and control mosquito pest and disease vector populations.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Geographic Information Systems (GIS), image analysis, and remote sensing comprise global information technologies that are used to characterize pest and vector populations of mosquitoes. At this national meeting, scientists from ARS and McNeese State University organized and convened a half-day sym...

  12. Fire controls population structure in four dominant tree species in a tropical savanna.

    PubMed

    Lehmann, Caroline E R; Prior, Lynda D; Bowman, David M J S

    2009-09-01

    The persistence of mesic savannas has been theorised as being dependent on disturbances that restrict the number of juveniles growing through the sapling size class to become fire-tolerant trees. We analysed the population structures of four dominant tropical savanna tree species from 30 locations in Kakadu National Park (KNP), northern Australia. We found that across KNP as a whole, the population size structures of these species do not exhibit recruitment bottlenecks. However, individual stands had multimodal size-class distributions and mixtures of tree species consistent with episodic and individualistic recruitment of co-occurring tree species. Using information theory and multimodel inference, we examined the relative importance of fire frequency, stand basal area and elevation difference between a site and permanent water in explaining variations in the proportion of sapling to adult stems in four dominant tree species. This showed that the proportion of the tree population made up of saplings was negatively related to both fire frequencies and stand basal area. Overall, fire frequency has density-dependent effects in the regulation of the transition of saplings to trees in this Australian savanna, due to interactions with stem size, regeneration strategies, growth rates and tree-tree competition. Although stable at the regional scale, the spatiotemporal variability of fire can result in structural and floristic diversity of savanna tree populations.

  13. Population dynamics of Varroa destructor (Acari: Varroidae) in commercial honey bee colonies and implications for control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Treatment schedules to maintain low levels of Varroa mites in honey bee colonies were tested in hives started from either package bees or splits of larger colonies. The schedules were developed based on predictions of Varroa population growth generated from a mathematical model of honey bee colony ...

  14. Recruitment issues when primary care population clusters are used in randomised controlled clinical trials: climbing mountains or pushing boulders uphill?

    PubMed

    Hoddinott, Pat; Britten, Jane; Harrild, Kirsten; Godden, David J

    2007-05-01

    Cluster randomised controlled trials for health promotion, education, public health or organisational change interventions are becoming increasingly common to inform evidence-based policy. However, there is little published methodological evidence on recruitment strategies for primary care population clusters. In this paper, we discuss how choosing which population cluster to randomise can impact on the practicalities of recruitment in primary care. We describe strategies developed through our experiences of recruiting primary care organisations to participate in a national randomised controlled trial of a policy to provide community breastfeeding groups for pregnant and breastfeeding mothers, the BIG (Breastfeeding in Groups) trial. We propose an iterative qualitative approach to recruitment; collecting data generated through the recruitment process, identifying themes and using the constant comparative method of analysis. This can assist in developing successful recruitment strategies and contrasts with the standardised approach commonly used when recruiting individuals to participate in randomised controlled trials. Recruiting primary care population clusters to participate in trials is currently an uphill battle in Britain. It is a complex process, which can benefit from applying qualitative methods to inform trial design and recruitment strategy. Recruitment could be facilitated if health service managers were committed to supporting peer reviewed, funded and ethics committee approved research at national level.

  15. Risk factors for pneumonic and ulceroglandular tularaemia in Finland: a population-based case-control study.

    PubMed

    Rossow, H; Ollgren, J; Klemets, P; Pietarinen, I; Saikku, J; Pekkanen, E; Nikkari, S; Syrjälä, H; Kuusi, M; Nuorti, J P

    2014-10-01

    Few population-based data are available on factors associated with pneumonic and ulceroglandular type B tularaemia. We conducted a case-control study during a large epidemic in 2000. Laboratory-confirmed case patients were identified through active surveillance and matched control subjects (age, sex, residency) from the national population information system. Data were collected using a self-administered questionnaire. A conditional logistic regression model addressing missing data with Bayesian full-likelihood modelling included 227 case patients and 415 control subjects; reported mosquito bites [adjusted odds ratio (aOR) 9·2, 95% confidence interval (CI) 4·4-22, population-attributable risk (PAR) 82%] and farming activities (aOR 4·3, 95% CI 2·5-7·2, PAR 32%) were independently associated with ulceroglandular tularaemia, whereas exposure to hay dust (aOR 6·6, 95% CI 1·9-25·4, PAR 48%) was associated with pneumonic tularaemia. Although the bulk of tularaemia type B disease burden is attributable to mosquito bites, risk factors for ulceroglandular and pneumonic forms of tularaemia are different, enabling targeting of prevention efforts accordingly.

  16. An application of control region sequence as a matrilineage marker for Elliot's pheasant of a zoo population.

    PubMed

    Jiang, Ping-Ping; Fang, Sheng-Gou; Ding, Ping

    2005-01-01

    Control region sequence, an mtDNA marker, was usually used in phylogenesis analysis in species level or genetic structure study among populations. In this study, enlightened by its character of maternal heredity in vertebrates, we used control region sequence as a matrilineage marker for Elliot's pheasant (Syrmaticus ellioti) of Ningbo Zoo population. In Ningbo Zoo, 36 individuals of Elliot's pheasant were descendants from three female founders introduced in 1988. Three control region haplotypes (Ha, Hb, Hc) were identified by six variable nucleotide positions among the control region sequences over 36 individuals. The number of haplotypes was accorded with the number of female founders. Total 20 individuals (C04, C06, C08-11, C14, C20, C21, C23-29, C32, C34-36) shared haplotype a, while 12 individuals (C01, C05, C07, C12, C13, C16-19, C22, C30, C33) shared haplotype b and 4 individuals (C02, C03, C15, C31) shared haplotype c. Those individuals sharing the same haplotype were offspring from one female founder. In other words, there were three maternal lineages and the simple relationship among individuals was indicated. As a result, it seemed that the control region sequence was a useful marker for identification of matrilineage in this study. Meanwhile, the matrilineage information may be compensatory data if there were no any pedigree records in captive species for breeding management.

  17. Estimation of the probability of exposure to metalworking fluids in a population-based case-control study

    PubMed Central

    Park, Dong-Uk; Colt, Joanne S.; Baris, Dalsu; Schwenn, Molly; Karagas, Margaret R.; Armenti, Karla R.; Johnson, Alison; Silverman, Debra T; Stewart, Patricia A

    2014-01-01

    We describe here an approach for estimating the probability that study subjects were exposed to metalworking fluids (MWFs) in a population-based case-control study of bladder cancer. Study subject reports on the frequency of machining and use of specific MWFs (straight, soluble, and synthetic/semi-synthetic) were used to estimate exposure probability when available. Those reports also were used to develop estimates for job groups, which were then applied to jobs without MWF reports. Estimates using both cases and controls and controls only were developed. The prevalence of machining varied substantially across job groups (10-90%), with the greatest percentage of jobs that machined being reported by machinists and tool and die workers. Reports of straight and soluble MWF use were fairly consistent across job groups (generally, 50-70%). Synthetic MWF use was lower (13-45%). There was little difference in reports by cases and controls vs. controls only. Approximately, 1% of the entire study population was assessed as definitely exposed to straight or soluble fluids in contrast to 0.2% definitely exposed to synthetic/semi-synthetics. A comparison between the reported use of the MWFs and the US production levels by decade found high correlations (r generally >0.7). Overall, the method described here is likely to have provided a systematic and reliable ranking that better reflects the variability of exposure to three types of MWFs than approaches applied in the past. PMID:25256317

  18. Vitamin D as a marker of cognitive decline in elderly Indian population

    PubMed Central

    Vedak, Tejal Kanhaiya; Ganwir, Vaishali; Shah, Arun B.; Pinto, Charles; Lele, Vikram R.; Subramanyam, Alka; Shah, Hina; Deo, Sudha Shrikant

    2015-01-01

    Objectives: Very few studies in India have addressed the role of vitamin D in cognitive function. The present study was conducted to assess the serum levels of 25-hydroxyvitamin D (25(OH)D) and its association with markers of cognitive impairment and homocysteine levels in the elderly Indian population. Materials and Methods: The study population consisted of patients with dementia (Group A, n = 32), mild cognitive impairment (MCI; Group B, n = 24), and elderly age-matched controls (Group C, n = 30). Measurement of serum levels of 25(OH)D and total homocysteine were done. Results: Significant decreased concentration of 25(OH)D and increased concentration of homocysteine was observed. Association of serum levels of vitamin D with markers of cognitive decline as well as serum homocysteine levels was observed in patients with dementia and MCI when compared to controls. Conclusion: Correlation of vitamin D with markers of cognitive decline and homocysteine opens a new door for early diagnosis of cognitive impairment. PMID:26425010

  19. IGF2BP2 rs11705701 polymorphisms are associated with prediabetes in a Chinese population: A population-based case-control study

    PubMed Central

    Han, Liyuan; Li, Yuanyuan; Tang, Linlin; Chen, Zhongwei; Zhang, Tao; Chen, Sihan; Liu, Shengyuan; Peng, Xiaolin; Mai, Yifeng; Zhuo, Renjie; Wang, Changyi; Duan, Shiwei

    2016-01-01

    Associations between insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) rs11705701, insulin receptor substrate 1 rs7578326, gastric inhibitory polypeptide receptor rs10423928 and transcription factor 7-like 2 rs12255372 gene polymorphisms with prediabetes and type 2 diabetes (T2D) have not been evaluated in the Han Chinese population. These four genetic variants were investigated for their associations with prediabetes and T2D among 490 unrelated patients with T2D, 471 patients with prediabetes and 575 healthy controls. Sequenom MassARRAY software was used to genotype the patients for these variants. The Generalized Multifactor Dimensionality Reduction method was used to analyze the gene-gene and gene-environment interactions. A breakdown analysis by gender revealed a significant association of IGF2BP2 rs11705701 with prediabetes under the dominant genetic model in females following application of the Bonferroni correction (odds ratio = 0.26; 95% confidence interval = 0.10–0.67; P=0.005). However, no significant associations were reported between any of the other three polymorphisms and T2D under any genetic models. Furthermore, there were no statistically significant gene-gene or gene-environment interactions when evaluated with the above association tests. The present case-control study reveals a significant association between IGF2BP2 rs11705701 and prediabetes in female patients. PMID:27588103

  20. Prevalence of Periodontitis in Patients with Established Rheumatoid Arthritis: A Swedish Population Based Case-Control Study

    PubMed Central

    Eriksson, Kaja; Nise, Lena; Kats, Anna; Luttropp, Elin; Catrina, Anca Irinel; Askling, Johan; Jansson, Leif; Alfredsson, Lars; Klareskog, Lars; Lundberg, Karin; Yucel-Lindberg, Tülay

    2016-01-01

    Introduction The possible hypothesis of a link between periodontitis and rheumatoid arthritis (RA), specifically anti-citrullinated protein antibody (ACPA) positive RA, prompted us to investigate the prevalence of periodontitis in the Swedish Epidemiological Investigation of RA (EIRA), a well-characterised population-based RA case-control cohort. Methods Periodontal status of 2,740 RA cases and 3,942 matched controls was retrieved through linking EIRA with the National Dental Health Registry (DHR), where dental diagnostic- and treatment codes on the adult Swedish population have been registered. Dental records from 100 cases and controls were reviewed to validate the periodontal diagnostic codes in DHR. Results The reviewed dental records confirmed 90% of the periodontitis diagnoses in DHR among RA cases, and 88% among controls. We found the positive predictive value of periodontitis diagnoses in the DHR to be 89% (95% CI 78 to 95%) with a sensitivity of 77% (95% CI: 65 to 86%). In total, 86% of EIRA participants were identified in DHR. The risk for periodontitis increased by age and current smoking status in both cases as well as controls. No significant differences in prevalence of periodontal disease in terms of gingivitis, periodontitis, peri-implantitis or increased risk for periodontitis or peri-implantitis were observed between RA cases and controls. In addition, there was no difference on the basis of seropositivity, ACPA or rheumatoid factor (RF), among patients with RA. Conclusions Our data verify that smoking and ageing are risk factors for periodontitis, both in RA and controls. We found no evidence of an increased prevalence of periodontitis in patients with established RA compared to healthy controls, and no differences based on ACPA or RF status among RA subjects. PMID:27203435

  1. Deferment of marriage and childbearing and effective control of population growth.

    PubMed

    Yang, S; Gu, B

    1991-08-01

    Deferment of marriage and childbearing reduces the number of children born by a couple in their lifetime and is the best way to depress population growth. This decreases the number of births in a given period and drops the fertility rate, which slows down the growth rate and size of the population. The extent of the impact varies with the parity specific age composition of women. Over a 100-year period, when the 1st birth is at 20 years and there are 2 children/family, the family size would be 8. When the 1st birth is at age 25, the family size becomes 6. Currently, China is encountering the peak of the baby boom. Unchecked population growth by these cohorts would mean the emergence of another baby boom. The consequences for the social and economic sectors would be great. With deferment of childbearing, the age composition of the population will be improved. Prior success in the practice of late marriage and late childbearing occurred in 1970s. Marriage age was raised from 22 years to 24 years by the late 1970s, which averted 30 million births within a decade. Unfortunately, the trends during the 1980s were a return to early marriage and childbearing such that by end of the 1980s 10% of married women had given birth by the age of 20. Had late marriage and late childbearing persisted through the 1980s, the mid-1991 population would have been 1.13 billion instead of 1.15 billion. The huge population requires a slower growth rate, but limiting the births/women has been beset with difficulties. All provinces need to target slower growth. Data from the 1988 National Sampling Survey of Fertility and Contraception reveal that 12 provinces had lowered age at 1st marriage. If the childbearing age can be raised by even 6 months reaching 23.5 years, 6 million births will be averted in the next 5 years. A 1-year to 24 years yields 10 million fewer births. It is reasonable to assume that it would be easier to convince young couples to defer their age at 1st births by 6 months

  2. Minding the gap: Frequency of indels in mtDNA control region sequence data and influence on population genetic analyses

    USGS Publications Warehouse

    Pearce, J.M.

    2006-01-01

    Insertions and deletions (indels) result in sequences of various lengths when homologous gene regions are compared among individuals or species. Although indels are typically phylogenetically informative, occurrence and incorporation of these characters as gaps in intraspecific population genetic data sets are rarely discussed. Moreover, the impact of gaps on estimates of fixation indices, such as FST, has not been reviewed. Here, I summarize the occurrence and population genetic signal of indels among 60 published studies that involved alignments of multiple sequences from the mitochondrial DNA (mtDNA) control region of vertebrate taxa. Among 30 studies observing indels, an average of 12% of both variable and parsimony-informative sites were composed of these sites. There was no consistent trend between levels of population differentiation and the number of gap characters in a data block. Across all studies, the average influence on estimates of ??ST was small, explaining only an additional 1.8% of among population variance (range 0.0-8.0%). Studies most likely to observe an increase in ??ST with the inclusion of gap characters were those with < 20 variable sites, but a near equal number of studies with few variable sites did not show an increase. In contrast to studies at interspecific levels, the influence of indels for intraspecific population genetic analyses of control region DNA appears small, dependent upon total number of variable sites in the data block, and related to species-specific characteristics and the spatial distribution of mtDNA lineages that contain indels. ?? 2006 Blackwell Publishing Ltd.

  3. Optimal control of population recovery--the role of economic restoration threshold.

    PubMed

    Lampert, Adam; Hastings, Alan

    2014-01-01

    A variety of ecological systems around the world have been damaged in recent years, either by natural factors such as invasive species, storms and global change or by direct human activities such as overfishing and water pollution. Restoration of these systems to provide ecosystem services entails significant economic benefits. Thus, choosing how and when to restore in an optimal fashion is important, but has not been well studied. Here we examine a general model where population growth can be induced or accelerated by investing in active restoration. We show that the most cost-effective method to restore an ecosystem dictates investment until the population approaches an 'economic restoration threshold', a density above which the ecosystem should be left to recover naturally. Therefore, determining this threshold is a key general approach for guiding efficient restoration management, and we demonstrate how to calculate this threshold for both deterministic and stochastic ecosystems. PMID:24341983

  4. Population-based surveillance for bacterial meningitis in the Dominican Republic: implications for control by vaccination.

    PubMed

    Gomez, E; Peguero, M; Sanchez, J; Castellanos, P L; Feris, J; Peña, C; Brudzinski-LaClaire, L; Levine, O S

    2000-12-01

    Quantifying the local burden of disease is an important step towards the introduction of new vaccines, such as Haemophilus influenzae type b (Hib) conjugate vaccine. We adapted a generic protocol developed by the World Health Organization for population-based surveillance of bacterial meningitis. All hospitals that admit paediatric patients with meningitis in the National District, Dominican Republic were included in the system and standard laboratory methods were used. The system identified 111 cases of confirmed bacterial meningitis. Hib was the leading cause of bacterial meningitis, followed by group B streptococcus, S. pneumoniae, and N. meningitidis. Unlike hospital-based case series, this population-based system was able to calculate incidence rates. The incidence of Hib meningitis was 13 cases per 100,000 children < 5 years old. The data from this study were used by the Ministry of Health to support the introduction of routine Hib vaccination and will be used to monitor its effectiveness.

  5. Optimal control of population recovery--the role of economic restoration threshold.

    PubMed

    Lampert, Adam; Hastings, Alan

    2014-01-01

    A variety of ecological systems around the world have been damaged in recent years, either by natural factors such as invasive species, storms and global change or by direct human activities such as overfishing and water pollution. Restoration of these systems to provide ecosystem services entails significant economic benefits. Thus, choosing how and when to restore in an optimal fashion is important, but has not been well studied. Here we examine a general model where population growth can be induced or accelerated by investing in active restoration. We show that the most cost-effective method to restore an ecosystem dictates investment until the population approaches an 'economic restoration threshold', a density above which the ecosystem should be left to recover naturally. Therefore, determining this threshold is a key general approach for guiding efficient restoration management, and we demonstrate how to calculate this threshold for both deterministic and stochastic ecosystems.

  6. Nutrient-Controlled Niche Differentiation of Western Lake Erie Cyanobacterial Populations Revealed via Metatranscriptomic Surveys.

    PubMed

    Harke, Matthew J; Davis, Timothy W; Watson, Susan B; Gobler, Christopher J

    2016-01-19

    Although toxic cyanobacterial blooms in western Lake Erie threaten drinking water supplies and are promoted by nutrient loading, the precise nutrient regime that selects specific cyanobacteria populations is poorly understood. Here, we assess shifts in cyanobacterial abundances and global gene-expression patterns in response to natural and manipulated gradients in nitrogen and phosphorus to identify gene pathways that facilitate dominance by different cyanobacteria. Gradients in soluble reactive phosphorus shaped cyanobacterial communities and elicited the largest transcriptomic responses. Under high-P conditions (closest to the mouth of the Maumee River), Anabaena and Planktothrix were the dominant cyanobacterial populations, and experimental P and ammonium enrichment promoted nitrogen fixation gene (nifH) expression in Anabaena. For Microcystis, experimental additions of P up-regulated genes involved in phage defense, genomic rearrangement, and nitrogen acquisition but led to lower abundances. Within offshore, low-P regions of the western basin of Lake Erie, Microcystis up-regulated genes associated with P scavenging (pstSCAB, phoX) and dominated cyanobacterial communities. Experimental additions of ammonium and urea did not alter Microcystis abundances but did up-regulate protease inhibitors (aer and mcn gene sets) and microcystin synthetase genes (mcy), with urea enrichment yielding significant increases in microcystin concentrations. Our findings suggest that management plans that reduce P loads alone may not significantly reduce the risk of cyanobacterial blooms in western Lake Erie but rather may promote a shift among cyanobacterial populations (Microcystis, Anabaena, and Planktothrix) toward a greater dominance by toxic strains of Microcystis.

  7. A conserved haplotype controls parallel adaptation in geographically distant salmonid populations

    PubMed Central

    MILLER, MICHAEL R; BRUNELLI, JOSEPH P; WHEELER, PAUL A; LIU, SIXIN; REXROAD, CAIRD E; PALTI, YNIV; DOE, CHRIS Q; THORGAARD, GARY H

    2012-01-01

    Salmonid fishes exhibit extensive local adaptations owing to abundant environmental variation and precise natal homing. This extensive local adaptation makes conservation and restoration of salmonids a challenge. For example, defining unambiguous units of conservation is difficult, and restoration attempts often fail owing to inadequate adaptive matching of translocated populations. A better understanding of the genetic architecture of local adaptation in salmonids could provide valuable information to assist in conserving and restoring natural populations of these important species. Here, we use a combination of laboratory crosses and next-generation sequencing to investigate the genetic architecture of the parallel adaptation of rapid development rate in two geographically and genetically distant populations of rainbow trout (Oncorhynchus mykiss). Strikingly, we find that not only is a parallel genetic mechanism used but that a conserved haplotype is responsible for this intriguing adaptation. The repeated use of adaptive genetic variation across distant geographical areas could be a general theme in salmonids and have important implications for conservation and restoration. PMID:21988725

  8. Asymmetric dispersal allows an upstream region to control population structure throughout a species' range.

    PubMed

    Pringle, James M; Blakeslee, April M H; Byers, James E; Roman, Joe

    2011-09-13

    In a single well-mixed population, equally abundant neutral alleles are equally likely to persist. However, in spatially complex populations structured by an asymmetric dispersal mechanism, such as a coastal population where larvae are predominantly moved downstream by currents, the eventual frequency of neutral haplotypes will depend on their initial spatial location. In our study of the progression of two spatially separate, genetically distinct introductions of the European green crab (Carcinus maenas) along the coast of eastern North America, we captured this process in action. We documented the shift of the genetic cline in this species over 8 y, and here we detail how the upstream haplotypes are beginning to dominate the system. This quantification of an evolving genetic boundary in a coastal system demonstrates that novel genetic alleles or haplotypes that arise or are introduced into upstream retention zones (regions whose export of larvae is not balanced by import from elsewhere) will increase in frequency in the entire system. This phenomenon should be widespread when there is asymmetrical dispersal, in the oceans or on land, suggesting that the upstream edge of a species' range can influence genetic diversity throughout its distribution. Efforts to protect the upstream edge of an asymmetrically dispersing species' range are vital to conserving genetic diversity in the species. PMID:21876126

  9. Study on genes of the serotonergic system and suicidal behavior: protocol for a case–control study in Mexican population

    PubMed Central

    2014-01-01

    Background Suicidal behavior is a leading cause of injury and death worldwide. Several studies have provided a possible relationship between genetic factors and suicidal behavior. Also, these studies have shown evidence for altered serotonergic neural transmission in the pathogenesis of suicidal behavior. In addition, genes pertaining to the serotonergic system have been proposed as candidates to establish biological correlates between suicidal behavior and the serotonergic system. The most studied genes are SCL6A4, HTR2A, HTR2C, HTR1A, HTR1B, TPH-1, and TPH-2. To get a comprehensive understanding of the association with suicidal behavior we will conduct genotype assays studies in a Mexican population. Methods/Design We will conduct a case–control study. The population sample will comprise adolescent and adult patients admitted for attempted of suicide and diagnosed by a psychiatrist. A peripheral blood sample will be taken from all the subjects (cases and controls). Genomic DNA from the leukocytes blood sample will be extracted. The genotypes of interest are distributed in the following genes: SCL6A4, HTR2A, HTR1A, HTR1B, HTR2C, TPH-2 and TPH-1. All the samples will be analyzed using a polymerase chain reaction (PCR) end-point method. We will evaluate the Hardy-Weinberg Equilibrium. The chi-squared test or Fisher’s exact test will be used to compare genotype and allele frequencies between control and case groups. The Quanto 1.2 software will measure the sample size of the association. For all the association analyses the level of significance will be set at p = 0.05 and the confidence interval at 95%. Discussion Suicidal behavior has been increase in Mexico, principally in young population. Our study will demonstrate the association between serotoninergic genes and suicide behavior in Mexican population. PMID:24495559

  10. TNFAIP3 rs2230926 polymorphisms in rheumatoid arthritis of southern Chinese Han population: a case-control study.

    PubMed

    Hao, Guifeng; Li, Yasong; Liu, Jinlin; Wo, Mingyi

    2014-01-01

    Polymorphism of tumor necrosis factor alpha-induced protein 3 (TNFAIP3) has been be related to various auto-immune diseases. Based on previous studies that the single nucleotide polymorphism (SNP) of rs2230926 was association with rheumatoid arthritis (RA) of Japanese, Caucasian population and the northern Chinese Han population, we tested the alleles and geno-type frequencies of rs2230926 in TNFAIP3 to investigate whether rs2230926 is susceptible to RA of southern Chinese Han population. In our case-control association study, 207 RA patients fulfilling the American College of Rheumatology (ACR) 1987 criteria were compared with 199 unrelated healthy subjects. After testing the alleles and genotype frequencies of rs2230926, the airwise linkage disequilibrium (LD) was computed and odd ration (OR) and 95% confidence intervals (95% CI) were used for evaluating the susceptibility to RA. The SNP of rs2230926 of the cases and control subjects were conformed to the Hardy-Weinberg equilibrium (P = 0.02257). The significantly statistical differences in alleles of T, G were founded in the cases and controls (P = 0.0027, OR 0.417, 95% CI 0.232-0.749); the genetic types of rs2230926 were associated with a susceptibility to RA, with OR 0.375 (95% CI 0.198-0.707, P = 0.0018). In the present study, our results indicated that the genetic polymorphism of rs2230926 in TNFAIP3 may be a susceptible factor conferring risk for RA in southern Chinese Han population. PMID:25674272

  11. Hyperlipidemia Is Associated with Chronic Urticaria: A Population-Based Study.

    PubMed

    Chung, Shiu-Dong; Wang, Kuo-Hsien; Tsai, Ming-Chieh; Lin, Herng-Ching; Chen, Chao-Hung

    2016-01-01

    The etiology of chronic urticaria (CU) is diverse, with chronic infections and inflammation being reported as considerable contributing factors. Although the prevalence of metabolic syndrome was found to be significantly elevated in patients with CU, no one has specifically estimated the effects on CU following hyperlipidemia. This study aimed to examine the association between hyperlipidemia and CU using a population-based dataset in Taiwan. This study included 9798 adults with CU as cases and 9798 sex- and age-matched controls. These patients were examined for whether they had received a prior diagnosis of hyperlipidemia. We used conditional logistic regression analyses to calculate the odds ratio (OR) and its corresponding 95% confidence interval (CI) for having been previously diagnosed with hyperlipidemia between cases and controls. In total, 7066 (36.1%) patients had received a prior diagnosis of hyperlipidemia, including 4287 (43.8%) among CU cases and 2779 (28.4%) among controls. The conditional logistic regression revealed that the OR of prior hyperlipidemia for cases was 1.97 (95% CI: 1.85~2.09) compared to the controls. Furthermore, compared to patients without CU, patients with CU independently experienced a 1.65-fold (95% CI = 1.55~1.76; p<0.001) increased risk of having a prior hyperlipidemia diagnosis, after adjustments were made. We concluded that CU was associated with having received a prior diagnosis of hyperlipidemia.

  12. Hyperlipidemia Is Associated with Chronic Urticaria: A Population-Based Study.

    PubMed

    Chung, Shiu-Dong; Wang, Kuo-Hsien; Tsai, Ming-Chieh; Lin, Herng-Ching; Chen, Chao-Hung

    2016-01-01

    The etiology of chronic urticaria (CU) is diverse, with chronic infections and inflammation being reported as considerable contributing factors. Although the prevalence of metabolic syndrome was found to be significantly elevated in patients with CU, no one has specifically estimated the effects on CU following hyperlipidemia. This study aimed to examine the association between hyperlipidemia and CU using a population-based dataset in Taiwan. This study included 9798 adults with CU as cases and 9798 sex- and age-matched controls. These patients were examined for whether they had received a prior diagnosis of hyperlipidemia. We used conditional logistic regression analyses to calculate the odds ratio (OR) and its corresponding 95% confidence interval (CI) for having been previously diagnosed with hyperlipidemia between cases and controls. In total, 7066 (36.1%) patients had received a prior diagnosis of hyperlipidemia, including 4287 (43.8%) among CU cases and 2779 (28.4%) among controls. The conditional logistic regression revealed that the OR of prior hyperlipidemia for cases was 1.97 (95% CI: 1.85~2.09) compared to the controls. Furthermore, compared to patients without CU, patients with CU independently experienced a 1.65-fold (95% CI = 1.55~1.76; p<0.001) increased risk of having a prior hyperlipidemia diagnosis, after adjustments were made. We concluded that CU was associated with having received a prior diagnosis of hyperlipidemia. PMID:26964045

  13. Strategic rat control for restoring populations of native species in forest fragments.

    PubMed

    Armstrong, Doug P; Gorman, Nic; Pike, Rhonda; Kreigenhofer, Brigitte; McArthur, Nikki; Govella, Susanne; Barrett, Paul; Richard, Yvan

    2014-06-01

    Forest fragments have biodiversity value that may be enhanced through management such as control of non-native predators. However, such efforts may be ineffective, and research is needed to ensure that predator control is done strategically. We used Bayesian hierarchical modeling to estimate fragment-specific effects of experimental rat control on a native species targeted for recovery in a New Zealand pastoral landscape. The experiment was a modified BACI (before-after-control-impact) design conducted over 6 years in 19 forest fragments with low-density subpopulations of North Island Robins (Petroica longipes). The aim was to identify individual fragments that not only showed clear benefits of rat control, but also would have a high probability of subpopulation growth even if they were the only fragment managed. We collected data on fecundity, adult and juvenile survival, and juvenile emigration, and modeled the data in an integrated framework to estimate the expected annual growth rate (λ) of each subpopulation with and without rat control. Without emigration, subpopulation growth was estimated as marginal (λ = 0.95-1.05) or negative (λ = 0.74-0.90) without rat control, but it was estimated as positive in all fragments (λ = 1.4-2.1) if rats were controlled. This reflected a 150% average increase in fecundity and 45% average increase in adult female survival. The probability of a juvenile remaining in its natal fragment was 0.37 on average, but varied with fragment connectivity. With juvenile emigration added, 6 fragments were estimated to have a high (>0.8) probability of being self-sustaining (λ > 1) with rat control. The key factors affecting subpopulation growth rates under rat control were low connectivity and stock fencing because these factors were associated with lower juvenile emigration and higher fecundity, respectively. However, there was also substantial random variation in adult survival among fragments, illustrating the importance of

  14. Strategic rat control for restoring populations of native species in forest fragments.

    PubMed

    Armstrong, Doug P; Gorman, Nic; Pike, Rhonda; Kreigenhofer, Brigitte; McArthur, Nikki; Govella, Susanne; Barrett, Paul; Richard, Yvan

    2014-06-01

    Forest fragments have biodiversity value that may be enhanced through management such as control of non-native predators. However, such efforts may be ineffective, and research is needed to ensure that predator control is done strategically. We used Bayesian hierarchical modeling to estimate fragment-specific effects of experimental rat control on a native species targeted for recovery in a New Zealand pastoral landscape. The experiment was a modified BACI (before-after-control-impact) design conducted over 6 years in 19 forest fragments with low-density subpopulations of North Island Robins (Petroica longipes). The aim was to identify individual fragments that not only showed clear benefits of rat control, but also would have a high probability of subpopulation growth even if they were the only fragment managed. We collected data on fecundity, adult and juvenile survival, and juvenile emigration, and modeled the data in an integrated framework to estimate the expected annual growth rate (λ) of each subpopulation with and without rat control. Without emigration, subpopulation growth was estimated as marginal (λ = 0.95-1.05) or negative (λ = 0.74-0.90) without rat control, but it was estimated as positive in all fragments (λ = 1.4-2.1) if rats were controlled. This reflected a 150% average increase in fecundity and 45% average increase in adult female survival. The probability of a juvenile remaining in its natal fragment was 0.37 on average, but varied with fragment connectivity. With juvenile emigration added, 6 fragments were estimated to have a high (>0.8) probability of being self-sustaining (λ > 1) with rat control. The key factors affecting subpopulation growth rates under rat control were low connectivity and stock fencing because these factors were associated with lower juvenile emigration and higher fecundity, respectively. However, there was also substantial random variation in adult survival among fragments, illustrating the importance of

  15. Husband's control and sexual coercion within marriage: findings from a population-based survey in Egypt.

    PubMed

    Kaplan, Rachel L; Khawaja, Marwan; Linos, Natalia

    2011-11-01

    This article examined sexual coercion within marriage in Egypt. Using cross-sectional survey data from a representative sample of married Egyptian women (N = 5,240), associations between forced intercourse and husband's control, as well as other relevant sociodemographic factors, were assessed through binary logistic regression models. The lifetime prevalence of forced intercourse was 6.2% and 4.6% during the past year, and husband's control was significantly associated with forced intercourse during a woman's lifetime (odds ratio = 3.5) and past year (odds ratio = 2.8). Interventions addressing gender patriarchy and men's control may decrease incidence of sexual coercion in Egypt and similar contexts.

  16. Use of a mathematical model to study the control measures of the cattle tick Boophilus microplus population in New Caledonia.

    PubMed

    Beugnet, F; Chalvet-Monfray, K; Sabatier, P

    1998-06-30

    Boophilus microplus is a common cattle tick of great economic importance in various tropical and subtropical countries like New Caledonia. The proposed model describes the population dynamics of female Boophilus microplus in the absence of resistant ticks. It is a system of six difference equations which can be mathematically analyzed. The analysis of the system shows the great importance of the eigenvalue denoted by lambda1. The population of ticks increases if lambda1 < 1 and decreases if lambda1 > 1. The lambda1 eigenvalue depends, in particular, on the parasitic surviving rate and encounter rate between the larvae and the cows. The treatments decrease the parasitic surviving rate as the agronomic measures decrease the encounter rate. This model permits to quantify the conditions of treatments (or of the efficacy of a vaccine) and of agronomic measures by which the populations are controlled. It shows that the different treatment rhythms and the presence or not of the wild or domestic refuges plays a major role on the dynamics of tick population.

  17. Genetic variation and evolutionary demography of Fenneropenaeus chinensis populations, as revealed by the analysis of mitochondrial control region sequences.

    PubMed

    Kong, Xiao Yu; Li, Yu Long; Shi, Wei; Kong, Jie

    2010-04-01

    Genetic variation and evolutionary demography of the shrimp Fenneropenaeus chinensis were investigated using sequence data of the complete mitochondrial control region (CR). Fragments of 993 bp of the CR were sequenced for 93 individuals from five localities over most of the species' range in the Yellow Sea and the Bohai Sea. There were 84 variable sites defining 68 haplotypes. Haplotype diversity levels were very high (0.95 ± 0.03-0.99 ± 0.02) in F. chinensis populations, whereas those of nucleotide diversity were moderate to low (0.66 ± 0.36%-0.84 ± 0.46%). Analysis of molecular variance and conventional population statistics (F(ST) ) revealed no significant genetic structure throughout the range of F. chinensis. Mismatch distribution, estimates of population parameters and neutrality tests revealed that the significant fluctuations and shallow coalescence of mtDNA genealogies observed were coincident with estimated demographic parameters and neutrality tests, in implying important past-population size fluctuations or range expansion. Isolation with Migration (IM) coalescence results suggest that F. chinensis, distributed along the coasts of northern China and the Korean Peninsula (about 1000 km apart), diverged recently, the estimated time-split being 12,800 (7,400-18,600) years ago.

  18. Subjective Cognitive Complaints and the Role of Executive Cognitive Functioning in the Working Population: A Case-Control Study

    PubMed Central

    Stenfors, Cecilia U. D.; Marklund, Petter; Magnusson Hanson, Linda L.; Theorell, Töres; Nilsson, Lars-Göran

    2013-01-01

    Background Cognitive functioning is important for managing work and life in general. However, subjective cognitive complaints (SCC), involving perceived difficulties with concentration, memory, decision making, and clear thinking are common in the general and working population and can be coupled with both lowered well-being and work ability. However, the relation between SCC and cognitive functioning across the adult age-span, and in the work force, is not clear as few population-based studies have been conducted on non-elderly adults. Thus, the present study aimed to test the relation between SCC and executive cognitive functioning in a population-based sample of employees. Methods Participants were 233 employees with either high (cases) or low (controls) levels of SCC. Group differences in neuropsychological test performance on three common executive cognitive tests were analysed through a set of analyses of covariance tests, including relevant covariates. Results & Conclusions In line with the a priori hypotheses, a high level of SCC was associated with significantly poorer executive cognitive performance on all three executive cognitive tests used, compared to controls with little SCC. Additionally, symptoms of depression, chronic stress and sleeping problems were found to play a role in the relations between SCC and executive cognitive functioning. No significant associations remained after adjusting for all these factors. The current findings contribute to an increased understanding of what characterizes SCC in the work force and may be used at different levels of prevention of- and intervention for SCC and related problems with executive cognitive functioning. PMID:24386185

  19. Finding the Balance: Fertility Control for the Management of Fragmented Populations of a Threatened Rock-Wallaby Species.

    PubMed

    Willers, Nicole; Martin, Graeme B; Matson, Phill; Mawson, Peter R; Morris, Keith; Bencini, Roberta

    2015-01-01

    Populations of Australian marsupials can become overabundant, resulting in detrimental impacts on the environment. For example, the threatened black-flanked rock-wallaby ( Petrogale lateralis lateralis ) has previously been perceived as overabundant and thus 'unwanted' when they graze crops and cause habitat degradation. Hormonally-induced fertility control has been increasingly used to manage population size in other marsupials where alternative management options are not viable. We tested whether deslorelin, a superagonist of gonadotropin-releasing hormone (GnRH), would suppress reproduction in free-living adult female rock-wallabies without adversely impacting body condition. We trapped, synchronised reproduction and allocated female rock-wallabies to a placebo implant (control, n = 22), one (n = 22) or two (n = 20) subcutaneous implants of deslorelin. Females were then recaptured over the following 36 months to monitor reproduction, including Luteinising Hormone levels, and body condition. Following treatment, diapaused blastocysts reactivated in five females and the resulting young were carried through to weaning. No wallabies treated with deslorelin, conceivede a new young for at least 27 months. We did not observe adverse effects on body condition on treated females. We conclude that deslorelin implants are effective for the medium-term suppression of reproduction in female black-flanked rock-wallabies and for managing overabundant populations of some marsupials.

  20. Method of application of tylosin, an antibiotic for American foulbrood control, with effects on small hive beetle (Coleoptera: Nitidulidae) populations.

    PubMed

    Elzen, P J; Westervelt, D; Causey, D; Ellis, J; Hepburn, H R; Neumann, P

    2002-12-01

    The method of application of the antibiotic tylosin (Tylan) for control of oxytetracycline-resistant American foulbrood (Paenibacillus larvae White) was tested in honeybee (Apis mellifera L.) colonies. A powdered sugar mixture with tylosin, applied as a dust, was efficacious in eliminating American foulbrood symptoms at a rate of 200-mg Tylan per 20 g of powdered sugar, applied at weekly intervals for 3 weeks. A second method of treatment consisting of Tylan mixed with granulated sugar and vegetable shortening and applied once as a patty, at an equivalent total dose as the dust method, to diseased colonies also effectively eliminated symptoms of disease. In all colonies treated with patties, however, small hive beetle (Aethina tumida Murray) populations significantly increased, compared with the powder sugar method or untreated controls. Bee populations in patty-treated colonies also were significantly reduced, most likely the result of the invasion and proliferation of adult and larval small hive beetles. Such reduction in colony strength was not seen in dust-treated colonies. Because of the obvious damaging populations of small hive beetles, concerns about development of disease resistance, unknown risks of residues, and lack of support by regulatory agencies for the use of the patty method, the use of the dust method of tylosin is greatly favored over the patty method.

  1. Modeling controlled nutrient release from a population of polymer coated fertilizers: statistically based model for diffusion release.

    PubMed

    Shaviv, Avi; Raban, Smadar; Zaidel, Elina

    2003-05-15

    A statistically based model for describing the release from a population of polymer coated controlled release fertilizer (CRF) granules by the diffusion mechanism was constructed. The model is based on a mathematical-mechanistic description of the release from a single granule of a coated CRF accounting for its complex and nonlinear nature. The large variation within populations of coated CRFs poses the need for a statistically based approach to integrate over the release from the individual granules within a given population for which the distribution and range of granule radii and coating thickness are known. The model was constructed and verified using experimentally determined parameters and release curves of polymer-coated CRFs. A sensitivity analysis indicated the importance of water permeability in controlling the lag period and that of solute permeability in governing the rate of linear release and the total duration of the release. Increasing the mean values of normally distributed granule radii or coating thickness, increases the lag period and the period of linear release. The variation of radii and coating thickness, within realistic ranges, affects the release only when the standard deviation is very large or when water permeability is reduced without affecting solute permeability. The model provides an effective tool for designing and improving agronomic and environmental effectiveness of polymer-coated CRFs. PMID:12785533

  2. Finding the Balance: Fertility Control for the Management of Fragmented Populations of a Threatened Rock-Wallaby Species.

    PubMed

    Willers, Nicole; Martin, Graeme B; Matson, Phill; Mawson, Peter R; Morris, Keith; Bencini, Roberta

    2015-01-01

    Populations of Australian marsupials can become overabundant, resulting in detrimental impacts on the environment. For example, the threatened black-flanked rock-wallaby ( Petrogale lateralis lateralis ) has previously been perceived as overabundant and thus 'unwanted' when they graze crops and cause habitat degradation. Hormonally-induced fertility control has been increasingly used to manage population size in other marsupials where alternative management options are not viable. We tested whether deslorelin, a superagonist of gonadotropin-releasing hormone (GnRH), would suppress reproduction in free-living adult female rock-wallabies without adversely impacting body condition. We trapped, synchronised reproduction and allocated female rock-wallabies to a placebo implant (control, n = 22), one (n = 22) or two (n = 20) subcutaneous implants of deslorelin. Females were then recaptured over the following 36 months to monitor reproduction, including Luteinising Hormone levels, and body condition. Following treatment, diapaused blastocysts reactivated in five females and the resulting young were carried through to weaning. No wallabies treated with deslorelin, conceivede a new young for at least 27 months. We did not observe adverse effects on body condition on treated females. We conclude that deslorelin implants are effective for the medium-term suppression of reproduction in female black-flanked rock-wallabies and for managing overabundant populations of some marsupials. PMID:26694471

  3. Quantitative trait locus mapping with background control in genetic populations of clonal F1 and double cross

    PubMed Central

    Zhang, Luyan; Li, Huihui; Ding, Junqiang; Wu, Jianyu

    2015-01-01

    Abstract In this study, we considered five categories of molecular markers in clonal F1 and double cross populations, based on the number of distinguishable alleles and the number of distinguishable genotypes at the marker locus. Using the completed linkage maps, incomplete and missing markers were imputed as fully informative markers in order to simplify the linkage mapping approaches of quantitative trait genes. Under the condition of fully informative markers, we demonstrated that dominance effect between the female and male parents in clonal F1 and double cross populations can cause the interactions between markers. We then developed an inclusive linear model that includes marker variables and marker interactions so as to completely control additive effects of the female and male parents, as well as the dominance effect between the female and male parents. The linear model was finally used for background control in inclusive composite interval mapping (ICIM) of quantitative trait locus (QTL). The efficiency of ICIM was demonstrated by extensive simulations and by comparisons with simple interval mapping, multiple‐QTL models and composite interval mapping. Finally, ICIM was applied in one actual double cross population to identify QTL on days to silking in maize. PMID:25881980

  4. Modeling controlled nutrient release from a population of polymer coated fertilizers: statistically based model for diffusion release.

    PubMed

    Shaviv, Avi; Raban, Smadar; Zaidel, Elina

    2003-05-15

    A statistically based model for describing the release from a population of polymer coated controlled release fertilizer (CRF) granules by the diffusion mechanism was constructed. The model is based on a mathematical-mechanistic description of the release from a single granule of a coated CRF accounting for its complex and nonlinear nature. The large variation within populations of coated CRFs poses the need for a statistically based approach to integrate over the release from the individual granules within a given population for which the distribution and range of granule radii and coating thickness are known. The model was constructed and verified using experimentally determined parameters and release curves of polymer-coated CRFs. A sensitivity analysis indicated the importance of water permeability in controlling the lag period and that of solute permeability in governing the rate of linear release and the total duration of the release. Increasing the mean values of normally distributed granule radii or coating thickness, increases the lag period and the period of linear release. The variation of radii and coating thickness, within realistic ranges, affects the release only when the standard deviation is very large or when water permeability is reduced without affecting solute permeability. The model provides an effective tool for designing and improving agronomic and environmental effectiveness of polymer-coated CRFs.

  5. Quantitative trait locus mapping with background control in genetic populations of clonal F1 and double cross.

    PubMed

    Zhang, Luyan; Li, Huihui; Ding, Junqiang; Wu, Jianyu; Wang, Jiankang

    2015-12-01

    In this study, we considered five categories of molecular markers in clonal F1 and double cross populations, based on the number of distinguishable alleles and the number of distinguishable genotypes at the marker locus. Using the completed linkage maps, incomplete and missing markers were imputed as fully informative markers in order to simplify the linkage mapping approaches of quantitative trait genes. Under the condition of fully informative markers, we demonstrated that dominance effect between the female and male parents in clonal F1 and double cross populations can cause the interactions between markers. We then developed an inclusive linear model that includes marker variables and marker interactions so as to completely control additive effects of the female and male parents, as well as the dominance effect between the female and male parents. The linear model was finally used for background control in inclusive composite interval mapping (ICIM) of quantitative trait locus (QTL). The efficiency of ICIM was demonstrated by extensive simulations and by comparisons with simple interval mapping, multiple-QTL models and composite interval mapping. Finally, ICIM was applied in one actual double cross population to identify QTL on days to silking in maize.

  6. Modification of Traffic-related Respiratory Response by Asthma Control in a Population of Car Commuters

    PubMed Central

    Mirabelli, Maria C.; Golan, Rachel; Greenwald, Roby; Raysoni, Amit U.; Holguin, Fernando; Kewada, Priya; Winquist, Andrea; Flanders, W. Dana; Sarnat, Jeremy A.

    2015-01-01

    Background Effects of traffic-related exposures on respiratory health are well documented, but little information is available about whether asthma control influences individual susceptibility. We analyzed data from the Atlanta Commuter Exposure study to evaluate modification of associations between rush-hour commuting, in-vehicle air pollution, and selected respiratory health outcomes by asthma control status. Methods Between 2009 and 2011, 39 adults participated in Atlanta Commuter Exposure, and each conducted two scripted rush-hour highway commutes. In-vehicle particulate components were measured during all commutes. Among adults with asthma, we evaluated asthma control by questionnaire and spirometry. Exhaled nitric oxide, forced expiratory volume in 1 second (FEV1), and other metrics of respiratory health were measured precommute and 0, 1, 2, and 3 hours postcommute. We used mixed effects linear regression to evaluate associations between commute-related exposures and postcommute changes in metrics of respiratory health by level of asthma control. Results We observed increased exhaled nitric oxide across all levels of asthma control compared with precommute measurements, with largest postcommute increases observed among participants with below-median asthma control (2 hours postcommute: 14.6% [95% confidence interval {CI} = 5.7, 24.2]; 3 hours postcommute: 19.5% [95% CI = 7.8, 32.5]). No associations between in-vehicle pollutants and percent of predicted FEV1 were observed, although higher PM2.5 was associated with lower FEV1 % predicted among participants with below-median asthma control (3 hours postcommute: −7.2 [95% CI = −11.8, −2.7]). Conclusions Level of asthma control may influence respiratory response to in-vehicle exposures experienced during rush-hour commuting. PMID:25901844

  7. Schistosomiasis in a migrating population in the lake region of China and its potential impact on control operation.

    PubMed

    Cao, Chun-li; Bao, Zi-ping; Li, Shi-zhu; Wei, Wang-yuan; Yi, Ping; Yu, Qing; Zhu, Hong-qing; Xu, Jing; Guo, Jia-gang; Feng, Zheng

    2015-05-01

    Coverage of migrating people in schistosomiasis control program is a growing concern in China. Schistosomiasis caused by Schistosoma japonicum is still one of the major infectious diseases of public health importance in China though tremendous efforts have been made to control the transmission over the past decades. Along with the rapid social-economic development, migrant population has been remarkably increasing across the country. The infected migrants may introduce a new souse of infection to endemic areas or the areas where the transmission had been controlled or interrupted but the intermediate host Oncomelania snail is still present. Preliminary studies for surveillance on schistosomiasis prevalence in migrants were reported, but there is little basic information provided. We carried out an investigation on the prevalence in immigrants, emigrants and permanent residents in three villages of Hunan province located in the main endemic area of lake region, and analyzed the potential impact of migration on control practice. In the study villages, the migrant population accounts for 53.6% of the total. Schistosoma infection was detected by modified Kato-Katz method and miracidium hatching test. Questionnaire survey was conducted comprising knowledge of disease and its transmission, water contact, personal protective measures, and whether examined and treated after water contact. The survey indicated that the migrants and permanent residents had similar life style, and the majority of them experienced water contact in agricultural work or routine life activities. However, the infection rate in immigrants was significantly higher than that in permanent residents. It was also found that the migrants had significantly less knowledge about the disease than the permanent residents, and took no personal protective measures. This is due to that the control program could not cover the migrants when they were absent at the time the program being implemented. The present

  8. Comprehensive Approach for Hypertension Control in Low-income Populations: Rationale and Study Design for the Hypertension Control Program in Argentina (HCPIA)

    PubMed Central

    Mills, Katherine T.; Rubinstein, Adolfo; Irazola, Vilma; Chen, Jing; Beratarrechea, Andrea; Poggio, Rosana; Dolan, Jacquelyn; Augustovski, Federico; Shi, Lizheng; Krousel-Wood, Marie; Bazzano, Lydia A.; He, Jiang

    2014-01-01

    Although the efficacy and effectiveness of lifestyle modifications and antihypertensive pharmaceutical treatment for the prevention and control of hypertension and concomitant cardiovascular disease have been demonstrated in randomized controlled trials, this scientific knowledge has not been fully applied in the general population, especially in low-income communities. This paper summarizes interventions to improve hypertension management and describes the rationale and study design for a cluster randomized trial testing whether a comprehensive intervention program within a national public primary care system will improve hypertension control among uninsured hypertensive men and women and their families. We will recruit 1,890 adults from 18 clinics within a public primary care network in Argentina. Clinic patients with uncontrolled hypertension, their spouses and hypertensive family members will be enrolled. The comprehensive intervention program targets the primary care system through health care provider education, a home-based intervention among patients and their families (home delivery of antihypertensive medication, self-monitoring of blood pressure, health education for medication adherence and lifestyle modification) conducted by community health workers, and a mobile health intervention. The primary outcome is net change in systolic blood pressure from baseline to month 18 between intervention and control groups among hypertensive study participants. The secondary outcomes are net change in diastolic blood pressure, blood pressure control, and cost-effectiveness of the intervention. This study will generate urgently needed data on effective, practical, and sustainable intervention programs aimed at controlling hypertension and concomitant cardiovascular disease in underserved populations in low- and middle-income countries. PMID:24978148

  9. Controlling the Growth of Future LEO Debris Populations with Active Debris Removal

    NASA Technical Reports Server (NTRS)

    Liou, J.-C.; Johnson, N. L.; Hill, N. M.

    2008-01-01

    Active debris removal (ADR) was suggested as a potential means to remediate the low Earth orbit (LEO) debris environment as early as the 1980s. The reasons ADR has not become practical are due to its technical difficulties and the high cost associated with the approach. However, as the LEO debris populations continue to increase, ADR may be the only option to preserve the near-Earth environment for future generations. An initial study was completed in 2007 to demonstrate that a simple ADR target selection criterion could be developed to reduce the future debris population growth. The present paper summarizes a comprehensive study based on more realistic simulation scenarios, including fragments generated from the 2007 Fengyun-1C event, mitigation measures, and other target selection options. The simulations were based on the NASA long-term orbital debris projection model, LEGEND. A scenario, where at the end of mission lifetimes, spacecraft and upper stages were moved to 25-year decay orbits, was adopted as the baseline environment for comparison. Different annual removal rates and different ADR target selection criteria were tested, and the resulting 200-year future environment projections were compared with the baseline scenario. Results of this parametric study indicate that (1) an effective removal strategy can be developed based on the mass and collision probability of each object as the selection criterion, and (2) the LEO environment can be stabilized in the next 200 years with an ADR removal rate of five objects per year.

  10. Optimal control strategies for disinfection of bacterial populations with persister and susceptible dynamics.

    PubMed

    Cogan, N G; Brown, Jason; Darres, Kyle; Petty, Katherine

    2012-09-01

    It is increasingly clear that bacteria manage to evade killing by antibiotics and antimicrobials in a variety of ways, including mutation, phenotypic variations, and formation of biofilms. With recent advances in understanding the dynamics of the tolerance mechanisms, there have been subsequent advances in understanding how to manipulate the bacterial environments to eradicate the bacteria. This study focuses on using mathematical techniques to find the optimal disinfection strategy to eliminate the bacteria while managing the load of antibiotic that is applied. In this model, the bacterial population is separated into those that are tolerant to the antibiotic and those that are susceptible to disinfection. There are transitions between the two populations whose rates depend on the chemical environment. Our results extend previous mathematical studies to include more realistic methods of applying the disinfectant. The goal is to provide experimentally testable predictions that have been lacking in previous mathematical studies. In particular, we provide the optimal disinfection protocol under a variety of assumptions within the model that can be used to validate or invalidate our simplifying assumptions and the experimental hypotheses that we used to develop the model. We find that constant dosing is not the optimal method for disinfection. Rather, cycling between application and withdrawal of the antibiotic yields the fastest killing of the bacteria.

  11. Antiglycolipid antibodies, immunoglobulins and paraproteins in motor neuron disease: a population based case-control study.

    PubMed

    Willison, H J; Chancellor, A M; Paterson, G; Veitch, J; Singh, S; Whitelaw, J; Kennedy, P G; Warlow, C P

    1993-02-01

    The role of humoral autoimmune factors in the pathogenesis of motor neuron disease (MND) is currently under considerable scrutiny. In particular, there have been many reports of abnormal serum immunoglobulin patterns and elevated titres of anti-ganglioside antibodies in patients with MND. However, many of these studies may be biased by the selection criteria for patients and controls. In order to carefully address this issue we obtained 82 blood samples from consecutive MND patients identified through a national MND register in combination with 82 community controls matched for age, sex and geographical area. We used these samples to determine the frequency of monoclonal immunoglobulins (mIgs) and measure the levels of serum immunoglobulins and anti-GM1 ganglioside antibodies in sporadic cases of MND in comparison with normal controls. Serum mIgs detected using high resolution and immunofixation agarose electrophoresis were present in 1.2% of MND patients and 2.4% of controls. Using a highly sensitive isoelectric focusing and immunoblotting method, monoclonal or oligoclonal immunoglobulins were found in 28% of MND patients and 27% of controls. Anti-GM1 antibodies were present in 26% of MND patients and 18% of controls (odds ratio = 1.5, 95%, CI 0.7-3.6) with no significant differences in titres between the 2 groups. Mean immunoglobulin G, A and M levels were equal in 2 groups. Thus, although alterations in these parameters were identified, we were unable to demonstrate any significant difference between MND patients and controls. We conclude that the majority of sporadic cases of MND are unlikely to have an autoimmune basis as judged by the lack of abnormalities in these parameters.

  12. Patient-related barriers to hypertension control in a Nigerian population

    PubMed Central

    Okwuonu, Chimezie Godswill; Ojimadu, Nnamdi Ezekiel; Okaka, Enajite Ibiene; Akemokwe, Fatai Momodu

    2014-01-01

    Background Hypertension control is a challenge globally. Barriers to optimal control exist at the patient, physician, and health system levels. Patient-related barriers in our environment are not clear. The aim of this study was to identify patient-related barriers to control of hypertension among adults with hypertension in a semiurban community in South-East Nigeria. Methods This was a cross-sectional descriptive study of patients with a diagnosis of hypertension and on antihypertensive medication. Results A total of 252 participants were included in the survey, and comprised 143 males (56.7%) and 109 females (43.3%). The mean age of the participants was 56.6±12.7 years, with a diagnosis of hypertension for a mean duration of 6.1±3.3 years. Among these patients, 32.9% had controlled blood pressure, while 39.3% and 27.8%, respectively, had stage 1 and stage 2 hypertension according to the Seventh Report of the Joint National Committee on Prevention, Detection and Evaluation of High Blood Pressure. Only 23.4% knew the consequences of poor blood pressure control and 64% were expecting a cure from treatment even when the cause of hypertension was not known. Furthermore, 68.7% showed low adherence to medication, the reported reasons for which included forgetfulness (61.2%), financial constraints (56.6%), high pill burden (22.5%), side effects of medication (17.3%), and low measured blood pressure (12.1%). Finally, knowledge and practice of the lifestyle modifications necessary for blood pressure control was inadequate among the participants. Conclusion Poor knowledge regarding hypertension, unrealistic expectations of treatment, poor adherence with medication, unawareness of lifestyle modification, and failure to apply these were identified as patient-related barriers to blood pressure control in this study. PMID:25061335

  13. Evaluation of 22 genetic variants with Crohn's Disease risk in the Ashkenazi Jewish population: a case-control study

    PubMed Central

    2011-01-01

    Background Crohn's disease (CD) has the highest prevalence among individuals of Ashkenazi Jewish (AJ) descent compared to non-Jewish Caucasian populations (NJ). We evaluated a set of well-established CD-susceptibility variants to determine if they can explain the increased CD risk in the AJ population. Methods We recruited 369 AJ CD patients and 503 AJ controls, genotyped 22 single nucleotide polymorphisms (SNPs) at or near 10 CD-associated genes, NOD2, IL23R, IRGM, ATG16L1, PTGER4, NKX2-3, IL12B, PTPN2, TNFSF15 and STAT3, and assessed their association with CD status. We generated genetic scores based on the risk allele count alone and the risk allele count weighed by the effect size, and evaluated their predictive value. Results Three NOD2 SNPs, two IL23R SNPs, and one SNP each at IRGM and PTGER4 were independently associated with CD risk. Carriage of 7 or more copies of these risk alleles or the weighted genetic risk score of 7 or greater correctly classified 92% (allelic count score) and 83% (weighted score) of the controls; however, only 29% and 47% of the cases were identified as having the disease, respectively. This cutoff was associated with a >4-fold increased disease risk (p < 10e-16). Conclusions CD-associated genetic risks were similar to those reported in NJ population and are unlikely to explain the excess prevalence of the disease in AJ individuals. These results support the existence of novel, yet unidentified, genetic variants unique to this population. Understanding of ethnic and racial differences in disease susceptibility may help unravel the pathogenesis of CD leading to new personalized diagnostic and therapeutic approaches. PMID:21548950

  14. Congenital adrenal hyperplasia and risk for psychiatric disorders in girls and women born between 1915 and 2010: A total population study.

    PubMed

    Engberg, Hedvig; Butwicka, Agnieszka; Nordenström, Anna; Hirschberg, Angelica Lindén; Falhammar, Henrik; Lichtenstein, Paul; Nordenskjöld, Agneta; Frisén, Louise; Landén, Mikael

    2015-10-01

    Congenital adrenal hyperplasia (CAH) is a chronic condition and individuals are exposed to elevated androgen levels in utero as a result of the endogenous cortisol deficiency. Prenatal androgen exposure has been suggested to influence mental health, but population based studies on psychiatric morbidity among girls and women with CAH are lacking. Therefore, we performed a cohort study based on Swedish nationwide registers linked with the national CAH register. Girls and women with CAH due to 21-hydroxylase deficiency (n = 335) born between January 1915 and January 2010 were compared with aged-matched female (n = 33500) and male controls (n = 33500). Analyses were stratified by phenotype [salt wasting (SW), simple virilizing (SV), and non-classical type (NC)] and by CYP21A2 genotype subgroups (null, I2splice, I172N, and P30L). Results are presented as estimated risks (OR, 95%CI) of psychiatric disorders among girls and women with CAH compared with age-matched controls. Any psychiatric diagnoses were more common in CAH females compared with female and male population controls [1.9 (1.4-2.5), and 2.2 (1.7-2.9)]. In particular, the risk of alcohol misuse was increased compared with female and male population controls [2.8 (1.7-4.7) and 2.1 (1.2-3.5)], and appeared most common among the girls and women with the most severe null genotype [6.7 (2.6-17.8)]. The risk of stress and adjustment disorders was doubled compared with female population controls [2.1 (1.3-3.6)]. Girls and women with CAH have an increased risk of psychiatric disorders in general and substance use disorders in particular compared with unexposed females, with the highest risk among those with the most severe genotype. Prenatal androgen exposure and deficient endogenous cortisol and/or adrenaline production may provide explanations for these findings, but other factors related to CAH cannot be excluded. PMID:26184920

  15. Reducing Eurasian wild boar (Sus scrofa) population density as a measure for bovine tuberculosis control: effects in wild boar and a sympatric fallow deer (Dama dama) population in Central Spain.

    PubMed

    García-Jiménez, W L; Fernández-Llario, P; Benítez-Medina, J M; Cerrato, R; Cuesta, J; García-Sánchez, A; Gonçalves, P; Martínez, R; Risco, D; Salguero, F J; Serrano, E; Gómez, L; Hermoso-de-Mendoza, J

    2013-07-01

    Research on management of bovine tuberculosis (bTB) in wildlife reservoir hosts is crucial for the implementation of effective disease control measures and the generation of practical bTB management recommendations. Among the management methods carried out on wild species to reduce bTB prevalence, the control of population density has been frequently used, with hunting pressure a practical strategy to reduce bTB prevalence. However, despite the number of articles about population density control in different bTB wildlife reservoirs, there is little information regarding the application of such measures on the Eurasian wild boar (Sus scrofa), which is considered the main bTB wildlife reservoir within Mediterranean ecosystems. This study shows the effects of a management measure leading to a radical decrease in wild boar population density at a large hunting estate in Central Spain, in order to assess the evolution of bTB prevalence in both the wild boar population and the sympatric fallow deer population. The evolution of bTB prevalence was monitored in populations of the two wild ungulate species over a 5-year study period (2007-2012). The results showed that bTB prevalence decreased in fallow deer, corresponding to an important reduction in the wild boar population. However, this decrease was not homogeneous: in the last season of study there was an increase in bTB-infected male animals. Moreover, bTB prevalence remained high in the remnant wild boar population.

  16. Ecosystem scale declines in elk recruitment and population growth with wolf colonization: a before-after-control-impact approach.

    PubMed

    Christianson, David; Creel, Scott

    2014-01-01

    The reintroduction of wolves (Canis lupus) to Yellowstone provided the unusual opportunity for a quasi-experimental test of the effects of wolf predation on their primary prey (elk--Cervus elaphus) in a system where top-down, bottom-up, and abiotic forces on prey population dynamics were closely and consistently monitored before and after reintroduction. Here, we examined data from 33 years for 12 elk population segments spread across southwestern Montana and northwestern Wyoming in a large scale before-after-control-impact analysis of the effects of wolves on elk recruitment and population dynamics. Recruitment, as measured by the midwinter juvenile∶female ratio, was a strong determinant of elk dynamics, and declined by 35% in elk herds colonized by wolves as annual population growth shifted from increasing to decreasing. Negative effects of population density and winter severity on recruitment, long recognized as important for elk dynamics, were detected in uncolonized elk herds and in wolf-colonized elk herds prior to wolf colonization, but not after wolf colonization. Growing season precipitation and harvest had no detectable effect on recruitment in either wolf treatment or colonization period, although harvest rates of juveniles∶females declined by 37% in wolf-colonized herds. Even if it is assumed that mortality due to predation is completely additive, liberal estimates of wolf predation rates on juvenile elk could explain no more than 52% of the total decline in juvenile∶female ratios in wolf-colonized herds, after accounting for the effects of other limiting factors. Collectively, these long-term, large-scale patterns align well with prior studies that have reported substantial decrease in elk numbers immediately after wolf recolonization, relatively weak additive effects of direct wolf predation on elk survival, and decreased reproduction and recruitment with exposure to predation risk from wolves.

  17. Ecosystem scale declines in elk recruitment and population growth with wolf colonization: a before-after-control-impact approach.

    PubMed

    Christianson, David; Creel, Scott

    2014-01-01

    The reintroduction of wolves (Canis lupus) to Yellowstone provided the unusual opportunity for a quasi-experimental test of the effects of wolf predation on their primary prey (elk--Cervus elaphus) in a system where top-down, bottom-up, and abiotic forces on prey population dynamics were closely and consistently monitored before and after reintroduction. Here, we examined data from 33 years for 12 elk population segments spread across southwestern Montana and northwestern Wyoming in a large scale before-after-control-impact analysis of the effects of wolves on elk recruitment and population dynamics. Recruitment, as measured by the midwinter juvenile∶female ratio, was a strong determinant of elk dynamics, and declined by 35% in elk herds colonized by wolves as annual population growth shifted from increasing to decreasing. Negative effects of population density and winter severity on recruitment, long recognized as important for elk dynamics, were detected in uncolonized elk herds and in wolf-colonized elk herds prior to wolf colonization, but not after wolf colonization. Growing season precipitation and harvest had no detectable effect on recruitment in either wolf treatment or colonization period, although harvest rates of juveniles∶females declined by 37% in wolf-colonized herds. Even if it is assumed that mortality due to predation is completely additive, liberal estimates of wolf predation rates on juvenile elk could explain no more than 52% of the total decline in juvenile∶female ratios in wolf-colonized herds, after accounting for the effects of other limiting factors. Collectively, these long-term, large-scale patterns align well with prior studies that have reported substantial decrease in elk numbers immediately after wolf recolonization, relatively weak additive effects of direct wolf predation on elk survival, and decreased reproduction and recruitment with exposure to predation risk from wolves. PMID:25028933

  18. Ecosystem Scale Declines in Elk Recruitment and Population Growth with Wolf Colonization: A Before-After-Control-Impact Approach

    PubMed Central

    Christianson, David; Creel, Scott

    2014-01-01

    The reintroduction of wolves (Canis lupus) to Yellowstone provided the unusual opportunity for a quasi-experimental test of the effects of wolf predation on their primary prey (elk – Cervus elaphus) in a system where top-down, bottom-up, and abiotic forces on prey population dynamics were closely and consistently monitored before and after reintroduction. Here, we examined data from 33 years for 12 elk population segments spread across southwestern Montana and northwestern Wyoming in a large scale before-after-control-impact analysis of the effects of wolves on elk recruitment and population dynamics. Recruitment, as measured by the midwinter juvenile∶female ratio, was a strong determinant of elk dynamics, and declined by 35% in elk herds colonized by wolves as annual population growth shifted from increasing to decreasing. Negative effects of population density and winter severity on recruitment, long recognized as important for elk dynamics, were detected in uncolonized elk herds and in wolf-colonized elk herds prior to wolf colonization, but not after wolf colonization. Growing season precipitation and harvest had no detectable effect on recruitment in either wolf treatment or colonization period, although harvest rates of juveniles∶females declined by 37% in wolf-colonized herds. Even if it is assumed that mortality due to predation is completely additive, liberal estimates of wolf predation rates on juvenile elk could explain no more than 52% of the total decline in juvenile∶female ratios in wolf-colonized herds, after accounting for the effects of other limiting factors. Collectively, these long-term, large-scale patterns align well with prior studies that have reported substantial decrease in elk numbers immediately after wolf recolonization, relatively weak additive effects of direct wolf predation on elk survival, and decreased reproduction and recruitment with exposure to predation risk from wolves. PMID:25028933

  19. Investigating the factorial structure and availability of work time control in a representative sample of the Swedish working population

    PubMed Central

    Albrecht, Sophie C.; Kecklund, Göran; Tucker, Philip; Leineweber, Constanze

    2015-01-01

    Aims: Past research has often neglected the sub-dimensions of work time control (WTC). Moreover, differences in levels of WTC with respect to work and demographic characteristics have not yet been examined in a representative sample. We investigated these matters in a recent sample of the Swedish working population. Methods: The study was based on the 2014 data collection of the Swedish Longitudinal Occupational Survey of Health. We assessed the structure of the WTC measure using exploratory and confirmatory factor analysis. Differences in WTC by work and demographic characteristics were examined with independent sample t-tests, one-way ANOVAs and gender-stratified logistic regressions. Results: Best model fit was found for a two-factor structure that distinguished between control over daily hours and control over time off (root mean square error of approximation = 0.06; 95% CI 0.04 to 0.09; Comparative Fit Index (CFI) = 0.99). Women, shift and public-sector workers reported lower control in relation to both factors. Age showed small associations with WTC, while a stronger link was suggested for civil status and family situation. Night, roster and rotating shift work seemed to be the most influential factors on reporting low control over daily hours and time off. Conclusions: Our data confirm the two-dimensional structure underlying WTC, namely the components ‘control over daily hours’ and ‘control over time off’. Women, public-sector and shift workers reported lower levels of control. Future research should examine the public health implications of WTC, in particular whether increased control over daily hours and time off can reduce health problems associated with difficult working-time arrangements. PMID:26620363

  20. A Randomised Controlled Trial of Social Network Targeting to Maximise Population Behaviour Change

    PubMed Central

    Kim, David A.; Hwong, Alison R.; Stafford, Derek; Hughes, D. Alex; O’Malley, A. James; Fowler, James H.; Christakis, Nicholas A.

    2015-01-01

    Background Information and behaviour can spread through interpersonal ties. By targeting influential individuals, health interventions that harness the distributive properties of social networks may be made more effective and efficient than those that do not. Methods In this block-randomised trial of network targeting methods, we delivered two dissimilar public health interventions to 32 villages in rural Honduras (22–541 participants each; total study population of 5,773): chlorine for water purification, and multivitamins for micronutrient deficiencies. We blocked villages on the basis of network size, socioeconomic status, and baseline rates of water purification. We then randomised villages, separately for each intervention, to one of three targeting methods, introducing the interventions to 5% samples composed either of: (1) randomly selected villagers (n=9 villages for each intervention), (2) villagers with the most social ties (n=9), or (3) nominated friends of random villagers (n=9; the last strategy exploiting the “friendship paradox” of social networks). Primary endpoints were the proportion of available products redeemed by the entire population under each targeting method. Participants and data collectors were not aware of the targeting methods. The trial is registered with ClinicalTrials.gov (NCT01672580). Findings For each intervention, 9 villages (each with 1–20 initial target individuals) were randomised to each of the three targeting methods. Targeting the most highly connected individuals produced no greater adoption of the interventions than random targeting. Targeting nominated friends, however, increased adoption of the nutritional intervention by 12·2% compared to random targeting (95% CI, 6·9 to 17·9). Interpretation Introducing a health intervention to the nominated friends of random individuals can enhance that intervention’s diffusion by exploiting intrinsic properties of human social networks. This method has the additional

  1. Long-term assessment of wild boar harvesting and cattle removal for bovine tuberculosis control in free ranging populations.

    PubMed

    Mentaberre, Gregorio; Romero, Beatriz; de Juan, Lucía; Navarro-González, Nora; Velarde, Roser; Mateos, Ana; Marco, Ignasi; Olivé-Boix, Xavier; Domínguez, Lucas; Lavín, Santiago; Serrano, Emmanuel

    2014-01-01

    Wild boar is a recognized reservoir of bovine tuberculosis (TB) in the Mediterranean ecosystems, but information is scarce outside of hotspots in southern Spain. We describe the first high-prevalence focus of TB in a non-managed wild boar population in northern Spain and the result of eight years of TB management. Measures implemented for disease control included the control of the local wild boar population through culling and stamping out of a sympatric infected cattle herd. Post-mortem inspection for detection of tuberculosis-like lesions as well as cultures from selected head and cervical lymph nodes was done in 745 wild boar, 355 Iberian ibexes and five cattle between 2004 and 2012. The seasonal prevalence of TB reached 70% amongst adult wild boar and ten different spoligotypes and 13 MIRU-VNTR profiles were detected, although more than half of the isolates were included in the same clonal complex. Only 11% of infected boars had generalized lesions. None of the ibexes were affected, supporting their irrelevance in the epidemiology of TB. An infected cattle herd grazed the zone where 168 of the 197 infected boars were harvested. Cattle removal and wild boar culling together contributed to a decrease in TB prevalence. The need for holistic, sustained over time, intensive and adapted TB control strategies taking into account the multi-host nature of the disease is highlighted. The potential risk for tuberculosis emergence in wildlife scenarios where the risk is assumed to be low should be addressed. PMID:24558435

  2. Long-Term Assessment of Wild Boar Harvesting and Cattle Removal for Bovine Tuberculosis Control in Free Ranging Populations

    PubMed Central

    Mentaberre, Gregorio; Romero, Beatriz; de Juan, Lucía; Navarro-González, Nora; Velarde, Roser; Mateos, Ana; Marco, Ignasi; Olivé-Boix, Xavier; Domínguez, Lucas; Lavín, Santiago; Serrano, Emmanuel

    2014-01-01

    Wild boar is a recognized reservoir of bovine tuberculosis (TB) in the Mediterranean ecosystems, but information is scarce outside of hotspots in southern Spain. We describe the first high-prevalence focus of TB in a non-managed wild boar population in northern Spain and the result of eight years of TB management. Measures implemented for disease control included the control of the local wild boar population through culling and stamping out of a sympatric infected cattle herd. Post-mortem inspection for detection of tuberculosis-like lesions as well as cultures from selected head and cervical lymph nodes was done in 745 wild boar, 355 Iberian ibexes and five cattle between 2004 and 2012. The seasonal prevalence of TB reached 70% amongst adult wild boar and ten different spoligotypes and 13 MIRU-VNTR profiles were detected, although more than half of the isolates were included in the same clonal complex. Only 11% of infected boars had generalized lesions. None of the ibexes were affected, supporting their irrelevance in the epidemiology of TB. An infected cattle herd grazed the zone where 168 of the 197 infected boars were harvested. Cattle removal and wild boar culling together contributed to a decrease in TB prevalence. The need for holistic, sustained over time, intensive and adapted TB control strategies taking into account the multi-host nature of the disease is highlighted. The potential risk for tuberculosis emergence in wildlife scenarios where the risk is assumed to be low should be addressed. PMID:24558435

  3. Finding the Balance: Fertility Control for the Management of Fragmented Populations of a Threatened Rock-Wallaby Species

    PubMed Central

    Willers, Nicole; Martin, Graeme B.; Matson, Phill; Mawson, Peter R.; Morris, Keith; Bencini, Roberta

    2015-01-01

    Simple Summary Black-flanked rock-wallabies (Petrogale lateralis lateralis) can reach high numbers in fragmented populations in the West Australian wheat-belt, where they can damage crops and cause habitat degradation. As they are threatened, we wanted a non-permanent control method that did not adversely affect the body condition of treated females compared to untreated females, using body condition as an indicator of general health and fitness. We gave adult female rock-wallabies deslorelin contraceptive implants to suppress their fertility and monitored the impact for three years. Treated females did not conceive new young for over two years. We did not detect any negative effects on body condition, suggesting that deslorelin may be an effective tool for managing overabundant populations of marsupials. Abstract Populations of Australian marsupials can become overabundant, resulting in detrimental impacts on the environment. For example, the threatened black-flanked rock-wallaby (Petrogale lateralis lateralis) has previously been perceived as overabundant and thus ‘unwanted’ when they graze crops and cause habitat degradation. Hormonally-induced fertility control has been increasingly used to manage population size in other marsupials where alternative management options are not viable. We tested whether deslorelin, a superagonist of gonadotropin-releasing hormone (GnRH), would suppress reproduction in free-living adult female rock-wallabies without adversely impacting body condition. We trapped, synchronised reproduction and allocated female rock-wallabies to a placebo implant (control, n = 22), one (n = 22) or two (n = 20) subcutaneous implants of deslorelin. Females were then recaptured over the following 36 months to monitor reproduction, including Luteinising Hormone levels, and body condition. Following treatment, diapaused blastocysts reactivated in five females and the resulting young were carried through to weaning. No wallabies treated with

  4. Image-driven population analysis through mixture modeling.

    PubMed

    Sabuncu, Mert R; Balci, Serdar K; Shenton, Martha E; Golland, Polina

    2009-09-01

    We present iCluster, a fast and efficient algorithm that clusters a set of images while co-registering them using a parameterized, nonlinear transformation model. The output of the algorithm is a small number of template images that represent different modes in a population. This is in contrast with traditional, hypothesis-driven computational anatomy approaches that assume a single template to construct an atlas. We derive the algorithm based on a generative model of an image population as a mixture of deformable template images. We validate and explore our method in four experiments. In the first experiment, we use synthetic data to explore the behavior of the algorithm and inform a design choice on parameter settings. In the second experiment, we demonstrate the utility of having multiple atlases for the application of localizing temporal lobe brain structures in a pool of subjects that contains healthy controls and schizophrenia patients. Next, we employ iCluster to partition a data set of 415 whole brain MR volumes of subjects aged 18 through 96 years into three anatomical subgroups. Our analysis suggests that these subgroups mainly correspond to age groups. The templates reveal significant structural differences across these age groups that confirm previous findings in aging research. In the final experiment, we run iCluster on a group of 15 patients with dementia and 15 age-matched healthy controls. The algorithm produces two modes, one of which contains dementia patients only. These results suggest that the algorithm can be used to discover subpopulations that correspond to interesting structural or functional "modes."

  5. A Quality-Control Mechanism Removes Unfit Cells from a Population of Sporulating Bacteria.

    PubMed

    Tan, Irene S; Weiss, Cordelia A; Popham, David L; Ramamurthi, Kumaran S

    2015-09-28

    Recent discoveries of regulated cell death in bacteria have led to speculation about possible benefits that apoptosis-like pathways may confer to single-celled organisms. However, establishing how these pathways provide increased ecological fitness has remained difficult to determine. Here, we report a pathway in Bacillus subtilis in which regulated cell death maintains the fidelity of sporulation through selective removal of cells that misassemble the spore envelope. The spore envelope, which protects the dormant spore's genome from environmental insults, uses the protein SpoIVA as a scaffold for assembly. We found that disrupting envelope assembly activates a cell death pathway wherein the small protein CmpA acts as an adaptor to the AAA+ ClpXP protease to degrade SpoIVA, thereby halting sporulation and resulting in lysis of defective sporulating cells. We propose that removal of unfit cells from a population of terminally differentiating cells protects against evolutionary deterioration and ultimately loss of the sporulation program.

  6. A New Population of Parvocellular Oxytocin Neurons Controlling Magnocellular Neuron Activity and Inflammatory Pain Processing.

    PubMed

    Eliava, Marina; Melchior, Meggane; Knobloch-Bollmann, H Sophie; Wahis, Jérôme; da Silva Gouveia, Miriam; Tang, Yan; Ciobanu, Alexandru Cristian; Triana del Rio, Rodrigo; Roth, Lena C; Althammer, Ferdinand; Chavant, Virginie; Goumon, Yannick; Gruber, Tim; Petit-Demoulière, Nathalie; Busnelli, Marta; Chini, Bice; Tan, Linette L; Mitre, Mariela; Froemke, Robert C; Chao, Moses V; Giese, Günter; Sprengel, Rolf; Kuner, Rohini; Poisbeau, Pierrick; Seeburg, Peter H; Stoop, Ron; Charlet, Alexandre; Grinevich, Valery

    2016-03-16

    Oxytocin (OT) is a neuropeptide elaborated by the hypothalamic paraventricular (PVN) and supraoptic (SON) nuclei. Magnocellular OT neurons of these nuclei innervate numerous forebrain regions and release OT into the blood from the posterior pituitary. The PVN also harbors parvocellular OT cells that project to the brainstem and spinal cord, but their function has not been directly assessed. Here, we identified a subset of approximately 30 parvocellular OT neurons, with collateral projections onto magnocellular OT neurons and neurons of deep layers of the spinal cord. Evoked OT release from these OT neurons suppresses nociception and promotes analgesia in an animal model of inflammatory pain. Our findings identify a new population of OT neurons that modulates nociception in a two tier process: (1) directly by release of OT from axons onto sensory spinal cord neurons and inhibiting their activity and (2) indirectly by stimulating OT release from SON neurons into the periphery.

  7. Aqueous precipitation: Population balance modeling and control in multi-cation systems

    SciTech Connect

    Voigt, J.A.

    1996-03-01

    Efficient separation of metal species from aqueous streams by precipitation techniques requires a fundamental understanding of the processes that occur during precipitation. These processes include particle nucleation, particle growth by solute deposition, agglomerate formation, and agglomerate breakup. Population balance method has been used to develop a kinetic model that accounts for these competing kinetic processes. The usefulness of the model is illustrated through its application to precipitation of yttrium hydroxynitrate, YHN. Kinetic parameters calculated from the model equations and system-specific solution chemistry are used to describe several aspects of the effect of pH on YHN precipitation. Implications for simultaneous precipitation of more than one cation type are discussed with examples. Effects of solution chemistry, precipitator design, and solvent choice are considered.

  8. A New Population of Parvocellular Oxytocin Neurons Controlling Magnocellular Neuron Activity and Inflammatory Pain Processing.

    PubMed

    Eliava, Marina; Melchior, Meggane; Knobloch-Bollmann, H Sophie; Wahis, Jérôme; da Silva Gouveia, Miriam; Tang, Yan; Ciobanu, Alexandru Cristian; Triana del Rio, Rodrigo; Roth, Lena C; Althammer, Ferdinand; Chavant, Virginie; Goumon, Yannick; Gruber, Tim; Petit-Demoulière, Nathalie; Busnelli, Marta; Chini, Bice; Tan, Linette L; Mitre, Mariela; Froemke, Robert C; Chao, Moses V; Giese, Günter; Sprengel, Rolf; Kuner, Rohini; Poisbeau, Pierrick; Seeburg, Peter H; Stoop, Ron; Charlet, Alexandre; Grinevich, Valery

    2016-03-16

    Oxytocin (OT) is a neuropeptide elaborated by the hypothalamic paraventricular (PVN) and supraoptic (SON) nuclei. Magnocellular OT neurons of these nuclei innervate numerous forebrain regions and release OT into the blood from the posterior pituitary. The PVN also harbors parvocellular OT cells that project to the brainstem and spinal cord, but their function has not been directly assessed. Here, we identified a subset of approximately 30 parvocellular OT neurons, with collateral projections onto magnocellular OT neurons and neurons of deep layers of the spinal cord. Evoked OT release from these OT neurons suppresses nociception and promotes analgesia in an animal model of inflammatory pain. Our findings identify a new population of OT neurons that modulates nociception in a two tier process: (1) directly by release of OT from axons onto sensory spinal cord neurons and inhibiting their activity and (2) indirectly by stimulating OT release from SON neurons into the periphery. PMID:26948889

  9. Atmospheric control of Aedes aegypti populations in Buenos Aires (Argentina) and its variability

    NASA Astrophysics Data System (ADS)

    de Garín, A.; Bejarán, R. A.; Carbajo, A. E.; de Casas, S. C.; Schweigmann, N. J.

    The mosquito Aedes aegypti is the main urban vector responsible for the transmission of dengue fever and dengue hemorrhagic fever. The city of Buenos Aires, Argentina, is located at the southern end of the world distribution of the species. The population abundance of Ae. aegypti is mainly regulated by environmental factors. We calculated the potential number of times that a female could lay eggs during its mean life expectancy, based on potential egg production and daily meteorological records. The model considers those variables implying physical hazard to the survival of Ae. aegypti, mosquito flying activity and oviposition. The results, obtained after calibration and validation of the model with field observations, show significant correlation (P<0.001) for different lags depending on the life stage. From these results, more favorable atmospheric conditions for Ae. aegypti reproduction (linked to the urban climatic change) can be observed. The climatic variability in the last decade resembles conditions at the end of 19th century.

  10. Population size drives industrial Saccharomyces cerevisiae alcoholic fermentation and is under genetic control.

    PubMed

    Albertin, Warren; Marullo, Philippe; Aigle, Michel; Dillmann, Christine; de Vienne, Dominique; Bely, Marina; Sicard, Delphine

    2011-04-01

    Alcoholic fermentation (AF) conducted by Saccharomyces cerevisiae has been exploited for millennia in three important human food processes: beer and wine production and bread leavening. Most of the efforts to understand and improve AF have been made separately for each process, with strains that are supposedly well adapted. In this work, we propose a first comparison of yeast AFs in three synthetic media mimicking the dough/wort/grape must found in baking, brewing, and wine making. The fermentative behaviors of nine food-processing strains were evaluated in these media, at the cellular, populational, and biotechnological levels. A large variation in the measured traits was observed, with medium effects usually being greater than the strain effects. The results suggest that human selection targeted the ability to complete fermentation for wine strains and trehalose content for beer strains. Apart from these features, the food origin of the strains did not significantly affect AF, suggesting that an improvement program for a specific food processing industry could exploit the variability of strains used in other industries. Glucose utilization was analyzed, revealing plastic but also genetic variation in fermentation products and indicating that artificial selection could be used to modify the production of glycerol, acetate, etc. The major result was that the overall maximum CO(2) production rate (V(max)) was not related to the maximum CO(2) production rate per cell. Instead, a highly significant correlation between V(max) and the maximum population size was observed in all three media, indicating that human selection targeted the efficiency of cellular reproduction rather than metabolic efficiency. This result opens the way to new strategies for yeast improvement.

  11. Population size drives industrial Saccharomyces cerevisiae alcoholic fermentation and is under genetic control.

    PubMed

    Albertin, Warren; Marullo, Philippe; Aigle, Michel; Dillmann, Christine; de Vienne, Dominique; Bely, Marina; Sicard, Delphine

    2011-04-01

    Alcoholic fermentation (AF) conducted by Saccharomyces cerevisiae has been exploited for millennia in three important human food processes: beer and wine production and bread leavening. Most of the efforts to understand and improve AF have been made separately for each process, with strains that are supposedly well adapted. In this work, we propose a first comparison of yeast AFs in three synthetic media mimicking the dough/wort/grape must found in baking, brewing, and wine making. The fermentative behaviors of nine food-processing strains were evaluated in these media, at the cellular, populational, and biotechnological levels. A large variation in the measured traits was observed, with medium effects usually being greater than the strain effects. The results suggest that human selection targeted the ability to complete fermentation for wine strains and trehalose content for beer strains. Apart from these features, the food origin of the strains did not significantly affect AF, suggesting that an improvement program for a specific food processing industry could exploit the variability of strains used in other industries. Glucose utilization was analyzed, revealing plastic but also genetic variation in fermentation products and indicating that artificial selection could be used to modify the production of glycerol, acetate, etc. The major result was that the overall maximum CO(2) production rate (V(max)) was not related to the maximum CO(2) production rate per cell. Instead, a highly significant correlation between V(max) and the maximum population size was observed in all three media, indicating that human selection targeted the efficiency of cellular reproduction rather than metabolic efficiency. This result opens the way to new strategies for yeast improvement. PMID:21357433

  12. Neural Autoantibody Evaluation in Functional Gastrointestinal Disorders: A Population-Based Case–Control Study

    PubMed Central

    Pittock, Sean J.; Lennon, Vanda A.; Dege, Carissa L.; Talley, Nicholas J.; Richard Locke, G.

    2011-01-01

    Background Our goal is to investigate the serum profile of neural autoantibodies in community-based patients with irritable bowel syndrome (IBS) or functional dyspepsia. The pathogenesis of functional gastrointestinal (GI) disorders, including IBS and dyspepsia, are unknown. Theories range from purely psychological to autoimmune alterations in GI tract neuromuscular function. Methods The study subjects, based in Olmsted County, MN, reported symptoms of functional dyspepsia or IBS (n = 69), or were asymptomatic controls (n = 64). Their coded sera were screened for antibodies targeting neuronal, glial, and muscle autoantigens. Results The prevalence of neural autoantibodies with functional GI disorders did not differ significantly from controls (17% vs. 13%; P = 0.43). In no case was a neuronal or glial nuclear autoantibody or enteric neuronal autoantibody identified. Neuronal cation channel antibodies were identified in 9% of cases (voltage-gated potassium channel [VGKC] in one dyspepsia case and one IBS case, ganglionic acetylcholine receptor [AChR] in four IBS cases) and in 6% of controls (ganglionic AChR in one, voltage-gated calcium channel [VGCC], N-type, in two and VGKC in one; P = 0.36). The frequency of glutamic acid decarboxylase-65 (GAD65) autoantibodies was similar in cases (10%) and controls (5%; P = 0.23). Conclusions Our data do not support neural autoimmunity as the basis for most IBS or functional dyspepsia cases. PMID:21181442

  13. Physical control of patients on an inpatient setting: forensic vs. civil populations.

    PubMed

    Heilbrun, K; Golloway, G G; Shoukry, V E; Gustafson, D

    1995-01-01

    The current study examines the use of physical control (seclusion and restraint) in a sample of patients hospitalized in a public mental hospital during 1989. A total of 243 patient records involving physical control were examined; of these, 124 had been civilly committed and the remaining 119 were forensic (Incompetent to Stand Trial or Not Guilty by Reason of Insanity). Some 870 physical control events occurred in the sample, a rate that is intermediate when compared with other facilities described in the literature. Seclusion was employed most often (46% of events), with the combination of seclusion and restraint used in 32% of events and the remaining 22% of physical control events being restraint. Seclusion tended to be used more often with civilly committed patients, with restraint more frequently employed with forensic patients. Forensic patients differed from civil subjects in their greater frequency of threats, agitation, and verbal hostility. However, civil patients were more frequently aggressive toward others and destructive of property. These findings are discussed in the context of previous evidence also describing forensic patients as being perceived as more dangerous, but behaving in a fashion no more physically aggressive than civil patients.

  14. Zero Tolerance for Marginal Populations: Examining Neoliberal Social Controls in American Schools

    ERIC Educational Resources Information Center

    Sellers, Brian G.

    2013-01-01

    This study's purpose is to investigate the expansion of social control efforts in American elementary and secondary school settings, particularly the use of zero-tolerance policies. These policies entail automatic punishments, such as suspensions, expulsions, and referrals to the juvenile and criminal justice systems for a host of school-based…

  15. The Mortality Penalty of Incarceration: Evidence from a Population-based Case-control Study of Working-age Males.

    PubMed

    Pridemore, William Alex

    2014-05-01

    There is a growing body of research on the effects of incarceration on health, though there are few studies in the sociological literature of the association between incarceration and premature mortality. This study examined the risk of male premature mortality associated with incarceration. Data came from the Izhevsk (Russia) Family Study, a large-scale population-based case-control design. Cases (n = 1,750) were male deaths aged 25 to 54 in Izhevsk between October 2003 and October 2005. Controls (n = 1,750) were selected at random from a city population register. The key independent variable was lifetime prevalence of incarceration. I used logistic regression to estimate mortality odds ratios, controlling for age, hazardous drinking, smoking status, marital status, and education. Seventeen percent of cases and 5 percent of controls had been incarcerated. Men who had been incarcerated were more than twice as likely as those who had not to experience premature mortality (odds ratio = 2.2, 95 percent confidence interval: 1.6-3.0). Relative to cases with no prior incarceration, cases who had been incarcerated were more likely to die from infectious diseases, respiratory diseases, non-alcohol-related accidental poisonings, and homicide. Taken together with other recent research, these results from a rigorous case-control design reveal not only that incarceration has durable effects on illness, but that its consequences extend to a greater risk of early death. I draw on the sociology of health literature on exposure, stress, and social integration to speculate about the reasons for this mortality penalty of incarceration.

  16. The Mortality Penalty of Incarceration: Evidence from a Population-based Case-control Study of Working-age Males.

    PubMed

    Pridemore, William Alex

    2014-05-01

    There is a growing body of research on the effects of incarceration on health, though there are few studies in the sociological literature of the association between incarceration and premature mortality. This study examined the risk of male premature mortality associated with incarceration. Data came from the Izhevsk (Russia) Family Study, a large-scale population-based case-control design. Cases (n = 1,750) were male deaths aged 25 to 54 in Izhevsk between October 2003 and October 2005. Controls (n = 1,750) were selected at random from a city population register. The key independent variable was lifetime prevalence of incarceration. I used logistic regression to estimate mortality odds ratios, controlling for age, hazardous drinking, smoking status, marital status, and education. Seventeen percent of cases and 5 percent of controls had been incarcerated. Men who had been incarcerated were more than twice as likely as those who had not to experience premature mortality (odds ratio = 2.2, 95 percent confidence interval: 1.6-3.0). Relative to cases with no prior incarceration, cases who had been incarcerated were more likely to die from infectious diseases, respiratory diseases, non-alcohol-related accidental poisonings, and homicide. Taken together with other recent research, these results from a rigorous case-control design reveal not only that incarceration has durable effects on illness, but that its consequences extend to a greater risk of early death. I draw on the sociology of health literature on exposure, stress, and social integration to speculate about the reasons for this mortality penalty of incarceration. PMID:24793163

  17. A control profile of adult children of alcoholics: a preliminary investigation.

    PubMed

    Shapiro, D H; Weatherford, V; Kaufman, E; Broenen, R E

    1994-01-01

    In order to more precisely investigate the nature of control and self-control issues for adult children of alcoholics (ACA), a group of ACAs was compared to a group of sex and age matched healthy normals and a sex matched group of college students on the Shapiro Control Inventory (SCI). The SCI provides a profile that is both general domain (positive sense of control, desire/efforts for control, agency of control, and mode of control) and domain specific (body, mind, interpersonal, self, career, environment). Analysis of variance and subsequent planned comparisons on the SCI showed significant differences between the ACA and the two comparison groups in general domain sense of control, in three of the four general domain mode quadrants, and in the domain specific areas of body, mind, interpersonal, and career. Individual areas where ACA subjects felt most out of control were weight, significant other, and family of origin; 89.5% felt concern with self-concept, stress, and relationship with significant other. Although a small subset of ACAs had a strikingly high "in control" profile, most did not. Finally, the sense of control profile of ACAs is compared with two clinical populations--borderline and depression--and is shown to fall midway between the clinical and normative groups. Guidelines and suggestions for further research are offered.

  18. Human Population Problems

    ERIC Educational Resources Information Center

    Emmel, Thomas C.; Sligh, Michael M.

    1970-01-01

    Asserts that overpopulation is the most pressing world problem. Topics discussed include population control in primitive societies, population growth and control in modern societies, methods of motivational population control, consequences of no population control, and mass famines during the 1970's in underdeveloped countries. Cities 33…

  19. Controlling coherence via tuning of the population imbalance in a bipartite optical lattice

    NASA Astrophysics Data System (ADS)

    di Liberto, Marco Fedele

    2015-03-01

    The control of transport properties is a key tool at the basis of many technologically relevant effects in condensed matter. The clean and precisely controlled environment of ultracold atoms in optical lattices allows one to prepare simplified but instructive models, which can help to better understand the underlying physical mechanisms. Here we show that by tuning a structural deformation of the unit cell in a bipartite optical lattice, one can induce a phase transition from a superfluid into various Mott insulating phases forming a shell structure in the superimposed harmonic trap. The Mott shells are identified via characteristic features in the visibility of Bragg maxima in momentum spectra. The experimental findings are explained by Gutzwiller mean-field and quantum Monte Carlo calculations. Our system bears similarities with the loss of coherence in cuprate superconductors, known to be associated with the doping induced buckling of the oxygen octahedra surrounding the copper sites.

  20. Controlling coherence via tuning of the population imbalance in a bipartite optical lattice

    NASA Astrophysics Data System (ADS)

    di Liberto, M.; Comparin, T.; Kock, T.; Ölschläger, M.; Hemmerich, A.; Smith, C. Morais

    2014-12-01

    The control of transport properties is a key tool at the basis of many technologically relevant effects in condensed matter. The clean and precisely controlled environment of ultracold atoms in optical lattices allows one to prepare simplified but instructive models, which can help to better understand the underlying physical mechanisms. Here we show that by tuning a structural deformation of the unit cell in a bipartite optical lattice, one can induce a phase transition from a superfluid into various Mott insulating phases forming a shell structure in the superimposed harmonic trap. The Mott shells are identified via characteristic features in the visibility of Bragg maxima in momentum spectra. The experimental findings are explained by Gutzwiller mean-field and quantum Monte Carlo calculations. Our system bears similarities with the loss of coherence in cuprate superconductors, known to be associated with the doping-induced buckling of the oxygen octahedra surrounding the copper sites.

  1. Statin use and risk of glioma: population-based case-control analysis.

    PubMed

    Seliger, Corinna; Meier, Christoph Rudolf; Becker, Claudia; Jick, Susan Sara; Bogdahn, Ulrich; Hau, Peter; Leitzmann, Michael Fred

    2016-09-01

    Statins have been reported to decrease the incidence of cancer, but the risk of glioma among statin users has been investigated in only two prior observational studies, both of them suggesting a modest protective effect of statins. We conducted a matched case-control study using data from the UK-based Clinical Practice Research Datalink to analyse use of statins among 2469 cases with glioma and 24,690 controls. We performed conditional logistic regression analysis to calculate relative risks, estimated as odds ratios (ORs) with 95 % confidence intervals (CIs) adjusting for multiple confounding factors. As compared with non-use of statins, use of statins was not associated with risk of glioma (OR for ≥90 prescriptions=0.75; 95 % CI 0.48-1.17). Our findings do not support previous sparse evidence of a possible inverse association between statin use and glioma risk. PMID:27041698

  2. Controls of stream chemistry and fish populations in the Neversink watershed, Catskill Mountains, New York

    USGS Publications Warehouse

    Lawrence, Gregory B.; Burns, Douglas A.; Baldigo, Barry P.; Murdoch, Peter S.; Lovett, Gary M.

    2001-01-01

    The Neversink Watershed Study was initiated in 1991 to develop an understanding of the key natural processes that control water quality within the forested, 166 km 2 (64 mi 2 ),Neversink River watershed;part of the New York City drinking water supply system,in the Catskill Mountain region of New York.The study entailed (1)hydrological investigations of water movement from the atmosphere to streams,(2) biogeochemical investigations of nitrogen and calcium,important nutrients in forest and aquatic ecosystems whose availability has been altered by acidic deposition,(3)an investigation of elevational patterns in atmospheric deposition,and (4)fisheries investigations to determine the relative importance of physical habitat and acidic deposition in controlling the abundance and diversity of fish species in the watershed.This report summarizes the results of these investigations,which have also been presented, in detail,in peer-reviewed technical articles and reports that are cited throughout the text.

  3. Effects of land use on bird populations and pest control services on coffee farms.

    PubMed

    Railsback, Steven F; Johnson, Matthew D

    2014-04-22

    Global increases in both agriculture and biodiversity awareness raise a key question: Should cropland and biodiversity habitat be separated, or integrated in mixed land uses? Ecosystem services by wildlife make this question more complex. For example, birds benefit agriculture by preying on pest insects, but other habitat is needed to maintain the birds. Resulting land use questions include what areas and arrangements of habitat support sufficient birds to control pests, whether this pest control offsets the reduced cropland, and the comparative benefits of "land sharing" (i.e., mixed cropland and habitat) vs. "land sparing" (i.e., separate areas of intensive agriculture and habitat). Such questions are difficult to answer using field studies alone, so we use a simulation model of Jamaican coffee farms, where songbirds suppress the coffee berry borer (CBB). Simulated birds select habitat and prey in five habitat types: intact forest, trees (including forest fragments), shade coffee, sun coffee, and unsuitable habitat. The trees habitat type appears to be especially important, providing efficient foraging and roosting sites near coffee plots. Small areas of trees (but not forest alone) could support a sufficient number of birds to suppress CBB in sun coffee; the degree to which trees are dispersed within coffee had little effect. In simulations without trees, shade coffee supported sufficient birds to offset its lower yield. High areas of both trees and shade coffee reduced pest control because CBB was less often profitable prey. Because of the pest control service provided by birds, land sharing was predicted to be more beneficial than land sparing in this system. PMID:24711377

  4. Surveillance, insecticide resistance and control of an invasive Aedes aegypti (Diptera: Culicidae) population in California.

    PubMed

    Cornel, Anthony J; Holeman, Jodi; Nieman, Catelyn C; Lee, Yoosook; Smith, Charles; Amorino, Mark; Brisco, Katherine K; Barrera, Roberto; Lanzaro, Gregory C; Mulligan Iii, F Stephen

    2016-01-01

    The invasion and subsequent establishment in California of Aedes aegypti in 2013 has created new challenges for local mosquito abatement and vector control districts. Studies were undertaken to identify effective and economical strategies to monitor the abundance and spread of this mosquito species as well as for its control. Overall, BG Sentinel (BGS) traps were found to be the most sensitive trap type to measure abundance and spread into new locations. Autocidal-Gravid-Ovitraps (AGO-B), when placed at a site for a week, performed equally to BGS in detecting the presence of female Ae. aegypti. Considering operational cost and our findings, we recommend use of BGS traps for surveillance in response to service requests especially in locations outside the known infestation area. We recommend AGO-Bs be placed at fixed sites, cleared and processed once a week to monitor mosquito abundance within a known infestation area. Long-term high density placements of AGO-Bs were found to show promise as an environmentally friendly trap-kill control strategy. California Ae. aegypti were found to be homozygous for the V1016I mutation in the voltage gated sodium channel gene, which is implicated to be involved in insecticide resistance. This strain originating from Clovis, California was resistant to some pyrethroids but not to deltamethrin in bottle bio-assays. Sentinel cage ultra-low-volume (ULV) trials using a new formulation of deltamethrin (DeltaGard®) demonstrated that it provided some control (average of 56% death in sentinel cages in a 91.4 m spray swath) after a single truck mounted aerial ULV application in residential areas. PMID:27158450

  5. Effects of land use on bird populations and pest control services on coffee farms.

    PubMed

    Railsback, Steven F; Johnson, Matthew D

    2014-04-22

    Global increases in both agriculture and biodiversity awareness raise a key question: Should cropland and biodiversity habitat be separated, or integrated in mixed land uses? Ecosystem services by wildlife make this question more complex. For example, birds benefit agriculture by preying on pest insects, but other habitat is needed to maintain the birds. Resulting land use questions include what areas and arrangements of habitat support sufficient birds to control pests, whether this pest control offsets the reduced cropland, and the comparative benefits of "land sharing" (i.e., mixed cropland and habitat) vs. "land sparing" (i.e., separate areas of intensive agriculture and habitat). Such questions are difficult to answer using field studies alone, so we use a simulation model of Jamaican coffee farms, where songbirds suppress the coffee berry borer (CBB). Simulated birds select habitat and prey in five habitat types: intact forest, trees (including forest fragments), shade coffee, sun coffee, and unsuitable habitat. The trees habitat type appears to be especially important, providing efficient foraging and roosting sites near coffee plots. Small areas of trees (but not forest alone) could support a sufficient number of birds to suppress CBB in sun coffee; the degree to which trees are dispersed within coffee had little effect. In simulations without trees, shade coffee supported sufficient birds to offset its lower yield. High areas of both trees and shade coffee reduced pest control because CBB was less often profitable prey. Because of the pest control service provided by birds, land sharing was predicted to be more beneficial than land sparing in this system.

  6. Surveillance, insecticide resistance and control of an invasive Aedes aegypti (Diptera: Culicidae) population in California.

    PubMed

    Cornel, Anthony J; Holeman, Jodi; Nieman, Catelyn C; Lee, Yoosook; Smith, Charles; Amorino, Mark; Brisco, Katherine K; Barrera, Roberto; Lanzaro, Gregory C; Mulligan Iii, F Stephen

    2016-01-01

    The invasion and subsequent establishment in California of Aedes aegypti in 2013 has created new challenges for local mosquito abatement and vector control districts. Studies were undertaken to identify effective and economical strategies to monitor the abundance and spread of this mosquito species as well as for its control. Overall, BG Sentinel (BGS) traps were found to be the most sensitive trap type to measure abundance and spread into new locations. Autocidal-Gravid-Ovitraps (AGO-B), when placed at a site for a week, performed equally to BGS in detecting the presence of female Ae. aegypti. Considering operational cost and our findings, we recommend use of BGS traps for surveillance in response to service requests especially in locations outside the known infestation area. We recommend AGO-Bs be placed at fixed sites, cleared and processed once a week to monitor mosquito abundance within a known infestation area. Long-term high density placements of AGO-Bs were found to show promise as an environmentally friendly trap-kill control strategy. California Ae. aegypti were found to be homozygous for the V1016I mutation in the voltage gated sodium channel gene, which is implicated to be involved in insecticide resistance. This strain originating from Clovis, California was resistant to some pyrethroids but not to deltamethrin in bottle bio-assays. Sentinel cage ultra-low-volume (ULV) trials using a new formulation of deltamethrin (DeltaGard®) demonstrated that it provided some control (average of 56% death in sentinel cages in a 91.4 m spray swath) after a single truck mounted aerial ULV application in residential areas.

  7. Effects of land use on bird populations and pest control services on coffee farms

    PubMed Central

    Railsback, Steven F.; Johnson, Matthew D.

    2014-01-01

    Global increases in both agriculture and biodiversity awareness raise a key question: Should cropland and biodiversity habitat be separated, or integrated in mixed land uses? Ecosystem services by wildlife make this question more complex. For example, birds benefit agriculture by preying on pest insects, but other habitat is needed to maintain the birds. Resulting land use questions include what areas and arrangements of habitat support sufficient birds to control pests, whether this pest control offsets the reduced cropland, and the comparative benefits of “land sharing” (i.e., mixed cropland and habitat) vs. “land sparing” (i.e., separate areas of intensive agriculture and habitat). Such questions are difficult to answer using field studies alone, so we use a simulation model of Jamaican coffee farms, where songbirds suppress the coffee berry borer (CBB). Simulated birds select habitat and prey in five habitat types: intact forest, trees (including forest fragments), shade coffee, sun coffee, and unsuitable habitat. The trees habitat type appears to be especially important, providing efficient foraging and roosting sites near coffee plots. Small areas of trees (but not forest alone) could support a sufficient number of birds to suppress CBB in sun coffee; the degree to which trees are dispersed within coffee had little effect. In simulations without trees, shade coffee supported sufficient birds to offset its lower yield. High areas of both trees and shade coffee reduced pest control because CBB was less often profitable prey. Because of the pest control service provided by birds, land sharing was predicted to be more beneficial than land sparing in this system. PMID:24711377

  8. Water nitrates and CNS birth defects: a population-based case-control study

    SciTech Connect

    Arbuckle, T.E.; Sherman, G.J.; Corey, P.N.; Walters, D.; Lo, B.

    1988-03-01

    The relation between maternal exposure to nitrates in drinking water and risk of delivering an infant with a central nervous system (CNS) malformation was examined by means of a case-control study in New Brunswick, Canada. All cases of CNS defects for a high and a low prevalence area of New Brunswick, for the years 1973-1983, were included in the study. Controls were selected randomly from the livebirth files for the province, matched on county of maternal residence and date of birth. One hundred and thirty (130) cases were identified and individually matched with two controls each. Individual water samples were collected from the case and control mother's address given on the birth or stillbirth records. The study revealed that the effect of nitrate exposure in water was modified by whether the source of the drinking water was a private well or a public municipal distribution system. Compared to a baseline nitrate level of 0.1 ppm, exposure to nitrate levels of 26 ppm from private well water sources was associated with a moderate, but not statistically significant, increase in risk (risk odds ratio = 2.30; 95% confidence interval = 0.73-7.29). If the source of drinking water was a municipal distribution system or a private spring, an increase in nitrate exposure was associated with a decrease in risk of delivering a CNS-malformed infant; however, these effect estimates were not statistically significant. The positive increase in risk with nitrate exposure from well water sources requires further study using a larger case series and a larger proportion of exposures to nitrate levels exceeding 5 ppm.

  9. Surveillance, insecticide resistance and control of an invasive Aedes aegypti (Diptera: Culicidae) population in California

    PubMed Central

    Cornel, Anthony J.; Holeman, Jodi; Nieman, Catelyn C.; Lee, Yoosook; Smith, Charles; Amorino, Mark; Brisco, Katherine K.; Barrera, Roberto; Lanzaro, Gregory C.; Mulligan III, F. Stephen

    2016-01-01

    The invasion and subsequent establishment in California of Aedes aegypti in 2013 has created new challenges for local mosquito abatement and vector control districts. Studies were undertaken to identify effective and economical strategies to monitor the abundance and spread of this mosquito species as well as for its control. Overall, BG Sentinel (BGS) traps were found to be the most sensitive trap type to measure abundance and spread into new locations. Autocidal-Gravid-Ovitraps (AGO-B), when placed at a site for a week, performed equally to BGS in detecting the presence of female Ae. aegypti. Considering operational cost and our findings, we recommend use of BGS traps for surveillance in response to service requests especially in locations outside the known infestation area. We recommend AGO-Bs be placed at fixed sites, cleared and processed once a week to monitor mosquito abundance within a known infestation area. Long-term high density placements of AGO-Bs were found to show promise as an environmentally friendly trap-kill control strategy. California Ae. aegypti were found to be homozygous for the V1016I mutation in the voltage gated sodium channel gene, which is implicated to be involved in insecticide resistance. This strain originating from Clovis, California was resistant to some pyrethroids but not to deltamethrin in bottle bio-assays. Sentinel cage ultra-low-volume (ULV) trials using a new formulation of deltamethrin (DeltaGard®) demonstrated that it provided some control (average of 56% death in sentinel cages in a 91.4 m spray swath) after a single truck mounted aerial ULV application in residential areas. PMID:27158450

  10. Biogeochemical controls on the bacterial population in the eastern Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Neogi, S. B.; Koch, B. P.; Schmitt-Kopplin, P.; Pohl, C.; Kattner, G.; Yamasaki, S.; Lara, R. J.

    2011-08-01

    Little is known about bacterial dynamics in the oligotrophic ocean, particularly about its cultivable population. We examined the abundance of total and cultivable bacteria in relation to changes in biogeochemical conditions in the eastern Atlantic Ocean with special regard to Vibrio spp., a group of bacteria that can cause diseases in human and aquatic organisms. Surface, deep water and plankton samples (<20 μm, 20-55 μm and >55 μm) were collected between 50° N and 24° S. Chlorophyll-a was very low (<0.3 μg l-1) in most areas of the nutrient-poor Atlantic, except at a few locations near upwelling regions. In surface water, dissolved organic carbon (DOC) and nitrogen (DON) concentrations were 64-95 μM C and 2-10 μM N accounting for ≥90 % and ≥76 % of total organic C and N, respectively. DOC and DON gradually decreased to ~45 μM C and <5 μM N in the bottom water while dissolved inorganic nutrients (Si, P, N) increased with depth. In the surface layer, culture independent total bacteria, represented by 4´-6-diamidino-2-phenylindole (DAPI) counts, ranged mostly between 107 and 108 cells l-1, while cultivable bacterial counts (CBC) and Vibrio spp. were found at concentrations of 104-107 and 102-105 colony forming units (CFU) l-1, respectively. Most bacteria (>99 %) were found in the nanoplankton fraction (<20 μm), however, bacterial abundance did not correlate with suspended particulates (chlorophyll-a, particulate organic C and N). Instead, we found a highly significant correlation between bacterial abundance and temperature (p < 0.001) and a significant correlation with DOC and DON. Among the cultivable bacteria, the abundance of Vibrio was also highly significantly correlated with DOC and DON (p < 0.0005 and p < 0.005, respectively). In cold waters of the mid-pelagic and abyssal zones, CBC was 50 to 100-times lower than in the surface layer; however, cultivable Vibrio spp. could be isolated from the bathypelagic zone and even near the seafloor

  11. Algal populations controlled by fish herbivory across a wave exposure gradient on southern temperate shores.

    PubMed

    Taylor, David I; Schiel, David R

    2010-01-01

    Consumers that forage across habitats can affect communities by altering the abundance and distribution of key species. In marine communities, studies of trophic interactions have generally focused on the effects of herbivorous and predatory invertebrates on benthic algae and mussel populations. However, large mobile consumers that move across habitats, such as fishes, can strongly affect community dynamics through consumption of habitat-dominating species, but their effects often vary over environmental gradients. On temperate rocky shores, herbivorous fishes are generally a small part of the fish fauna compared to the tropics, and there is sparse evidence that they play a major direct role in algal community dynamics, particularly of large brown algae that dominate many reefs. In New Zealand, however, a wide-ranging herbivorous fish, Odax pullus, feeds exclusively on macroalgae, including Durvillaea antarctica, a large low-intertidal fucoid reaching 10 m in length and 70 kg in mass. In four experiments we tested the extent of fish herbivory and how it was affected by algal canopy structure across a gradient of wave exposure at multiple sites. Exclusion experiments showed that fish impacts greatly reduced the cover and biomass of Durvillaea and that these effects decreased with increasing wave stress and algal canopy cover, effectively restricting the alga to exposed conditions. Almost all plants were entirely removed by fish where there was a sparse algal canopy in sheltered and semi-exposed sites, but there was significantly less grazing in exposed sites. Recruit Durvillaea beneath canopies were less affected by fish grazing, but they grew slowly. Successful natural recruitment, therefore, occurred almost exclusively on exposed shores outside canopies where many plants escaped severe grazing, and growth to maturity was far greater than elsewhere. Such large and direct impacts on the local and regional distribution of large brown algal populations by mobile

  12. Estimation of the probability of exposure to machining fluids in a population-based case-control study.

    PubMed

    Park, Dong-Uk; Colt, Joanne S; Baris, Dalsu; Schwenn, Molly; Karagas, Margaret R; Armenti, Karla R; Johnson, Alison; Silverman, Debra T; Stewart, Patricia A

    2014-01-01

    We describe an approach for estimating the probability that study subjects were exposed to metalworking fluids (MWFs) in a population-based case-control study of bladder cancer. Study subject reports on the frequency of machining and use of specific MWFs (straight, soluble, and synthetic/semi-synthetic) were used to estimate exposure probability when available. Those reports also were used to develop estimates for job groups, which were then applied to jobs without MWF reports. Estimates using both cases and controls and controls only were developed. The prevalence of machining varied substantially across job groups (0.1->0.9%), with the greatest percentage of jobs that machined being reported by machinists and tool and die workers. Reports of straight and soluble MWF use were fairly consistent across job groups (generally 50-70%). Synthetic MWF use was lower (13-45%). There was little difference in reports by cases and controls vs. controls only. Approximately, 1% of the entire study population was assessed as definitely exposed to straight or soluble fluids in contrast to 0.2% definitely exposed to synthetic/semi-synthetics. A comparison between the reported use of the MWFs and U.S. production levels found high correlations (r generally >0.7). Overall, the method described here is likely to have provided a systematic and reliable ranking that better reflects the variability of exposure to three types of MWFs than approaches applied in the past. [Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resources: a list of keywords in the occupational histories that were used to link study subjects to the metalworking fluids (MWFs) modules; recommendations from the literature on selection of MWFs based on type of machining operation, the metal being machined and decade; popular additives to MWFs; the number and proportion of controls who

  13. Estimation of the probability of exposure to machining fluids in a population-based case-control study.

    PubMed

    Park, Dong-Uk; Colt, Joanne S; Baris, Dalsu; Schwenn, Molly; Karagas, Margaret R; Armenti, Karla R; Johnson, Alison; Silverman, Debra T; Stewart, Patricia A

    2014-01-01

    We describe an approach for estimating the probability that study subjects were exposed to metalworking fluids (MWFs) in a population-based case-control study of bladder cancer. Study subject reports on the frequency of machining and use of specific MWFs (straight, soluble, and synthetic/semi-synthetic) were used to estimate exposure probability when available. Those reports also were used to develop estimates for job groups, which were then applied to jobs without MWF reports. Estimates using both cases and controls and controls only were developed. The prevalence of machining varied substantially across job groups (0.1->0.9%), with the greatest percentage of jobs that machined being reported by machinists and tool and die workers. Reports of straight and soluble MWF use were fairly consistent across job groups (generally 50-70%). Synthetic MWF use was lower (13-45%). There was little difference in reports by cases and controls vs. controls only. Approximately, 1% of the entire study population was assessed as definitely exposed to straight or soluble fluids in contrast to 0.2% definitely exposed to synthetic/semi-synthetics. A comparison between the reported use of the MWFs and U.S. production levels found high correlations (r generally >0.7). Overall, the method described here is likely to have provided a systematic and reliable ranking that better reflects the variability of exposure to three types of MWFs than approaches applied in the past. [Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resources: a list of keywords in the occupational histories that were used to link study subjects to the metalworking fluids (MWFs) modules; recommendations from the literature on selection of MWFs based on type of machining operation, the metal being machined and decade; popular additives to MWFs; the number and proportion of controls who

  14. Medication use in patients with restless legs syndrome compared with a control population.

    PubMed

    Pearson, V E; Gamaldo, C E; Allen, R P; Lesage, S; Hening, W A; Earley, C J

    2008-01-01

    Primary restless legs syndrome (RLS) is a sensorimotor disorder causing chronic sleep deprivation in those with moderate to severe symptoms. It has been associated with other medical conditions, such as high blood pressure, depression and attention deficit hyperactive disorder (ADHD). If these conditions are more prevalent for RLS patients, then it would be expected RLS patients would use relatively more of the medications treating these conditions. Current medication use was obtained from 110 RLS patients and 54 age, race and gender-matched local-community controls. Each subject was diagnosed as primary RLS or having no indications for RLS by a clinician board-certified in sleep medicine. The RLS group used more medications than the control group even when medications used for treating RLS were excluded. Significantly more of the RLS patients than controls used anti-depressants, gastro-intestinal (GI) medications and asthma/allergy medications. RLS patients compared with those without RLS are more likely to use medications not related to treating RLS. Moreover they use medications for conditions that have not previously been considered related to RLS, i.e. GI and asthma/allergy conditions.

  15. Caffeine intake and low birth weight: a population-based case-control study.

    PubMed

    Santos, I S; Victora, C G; Huttly, S; Carvalhal, J B

    1998-04-01

    The authors conducted a matched case-control study to investigate the effects of caffeine intake during pregnancy on birth weight. From January to November 1992, in the first 24 hours after delivery, 1,205 mothers (401 cases and 804 controls) were interviewed and their newborns were examined to assess birth weight and gestational age by means of the method of Capurro et al. (J Pediatr 1978;93:120-2). The cases were children with birth weight < 2,500 g and gestational age > or = 28 weeks. Cases and controls were matched for time of birth and hospital of delivery and were recruited from the four maternity hospitals in Pelotas, southern Brazil. Daily maternal caffeine intake during pregnancy for each trimester was estimated. To assess caffeine intake, 10% of the mothers were reinterviewed at their households and samples of reported information on drip coffee and maté (a caffeine-containing drink widely used in South America) were collected and sent to the laboratory for caffeine determination through liquid chromatography. When instant coffee was reported, the weight of powder was measured using a portable scale, and caffeine intake was estimated from a reference table. Caffeine intake from tea, chocolate, soft drinks, and medicines was estimated from a reference table. Analyses were performed by conditional logistic regression. Crude analyses showed no effect of caffeine on low birth weight, preterm births or intrauterine growth retardation. The results did not change after allowing for confounders.

  16. Control of Risk Factors for Cardiovascular Disease among Multinational Patient Population in the Arabian Gulf

    PubMed Central

    Al-Zakwani, Ibrahim; Al-Mahmeed, Wael; Arafah, Mohamed; Al-Hinai, Ali T.; Shehab, Abdullah; Al-Tamimi, Omer; Al-Awadhi, Mahmoud; Al-Herz, Shorook; Al-Anazi, Faisal; Al-Nemer, Khalid; Metwally, Othman; Al-Khadra, Akram; Fakhry, Mohammed; Elghetany, Hossam; Medani, Abdel R.; Yusufali, Afzal H.; Al-Jassim, Obaid; Al-Hallaq, Omar; Baslaib, Fahad O.A.S.; Amin, Haitham; Santos, Raul D.; Al-Waili, Khalid; Al-Hashmi, Khamis; Al-Rasadi, Khalid

    2016-01-01

    We evaluated the control of cardiovascular disease (CVD) risk factors among patients with atherosclerotic cardiovascular disease (ASCVD) in the Centralized Pan-Middle East Survey on the undertreatment of hypercholesterolaemia (CEPHEUS) in the Arabian Gulf. Of the 4398 enrolled patients, overall mean age was 57 ± 11 years, 60% were males, 13% were smokers, 76% had diabetes, 71% had metabolic syndrome and 78% had very high ASCVD risk status. The proportion of subjects with body mass index <25 kg/m2, HbA1c <7% (in diabetics), low-density lipoprotein cholesterol (LDL-C) <2.6 mmol/L (100 mg/dL) and <1.8 mmol/L (70 mg/dL) for high and very high ASCVD risk cohorts, respectively and controlled blood pressure (<140/90 mmHg) was 14, 26, 31% and 60%, respectively. Only 1.4% of the participants had all of their CVD risk factors controlled with significant differences among the countries (P < .001). CVD risk goal attainment rates were significantly lower in those with very high ASCVD risk compared with those with high ASCVD risk status (P < .001). Females were also, generally, less likely to attain goals when compared with males (P < .001). PMID:26496982

  17. Polymorphisms of STAT4 and the risk of inflammatory bowel disease: A case-control study in Chinese Han population.

    PubMed

    Zhu, Houbao; Liu, Jianbing; Zhang, Hongxin; Wang, Zhengting; Liu, Jie; Lu, Shunyuan; Xu, Wangyang; Zhong, Jie; Wang, Zhugang

    2013-03-01

    Signal transducer and activator of transcription 4 (STAT4) is a transcription factor involved in the signaling pathways of several cytokines, playing an essential role in the development of inflammation in various immune-mediated diseases. Genetic association studies have shown that the STAT4 gene was significantly associated with inflammatory bowel disease (IBD) in Spanish and Caucasian populations. However, these associations in other ethnic populations remain unknown. In the present study, we evaluated the role of the STAT4 rs7574865 and rs7582694 polymorphisms on IBD in 562 unrelated Chinese Han subjects by assessing distributions of genotypes and allele frequencies. Results showed that neither rs7574865 [Crohn's disease (CD): P=0.66, odds ratio (OR) = 0.95, 95% confidence interval (CI) 0.74-1.21; ulcerative colitis (UC): P=0.43, OR=0.85, 95% CI 0.56-1.28; IBD: P=0.52, OR=0.93, 95% CI 0.73-1.17] nor rs7582694 (CD: P=0.40, OR=1.12, 95% CI 0.86-1.44; UC: P=0.50, OR=0.86, 95% CI 0.56-1.33; IBD: P=0.62, OR=1.06, 95% CI 0.83-1.36) was significantly associated with IBD, although the genotype frequency of rs7574865 varied in patients and the controls. In conclusion, our data did not support that STAT4 variants contribute to IBD susceptibility in the Chinese Han population. PMID:24648942

  18. Sleep quality among internally displaced Georgian adolescents and population-based controls.

    PubMed

    Sakhelashvili, Irine; Eliozishvili, Marine; Lortkipanidze, Nani; Oniani, Nikoloz; Cervena, Katerina; Darchia, Nato

    2016-09-01

    Sleep problems in children and adolescents are a significant public health concern and may be linked to a variety of psychoemotional difficulties. This study aimed to evaluate sleep quality and associated factors in conflict-affected Georgian adolescents after 9 months of forced displacement. Thirty-three internally displaced adolescents (mean age 11.4 years) and 33 adolescents (mean age 10.8 years) from the general population completed the Epworth Sleepiness Scale and the Children's Depression Inventory (CDI). Parents completed the Children's Sleep-Wake Scale and provided information on their socioeconomic status (SES) and the adolescents' sleep behavior, academic performance, and peer social relationships. The groups differed significantly in sleep quality, peer relationships, SES, and CDI scores. In the internally displaced group, the only significant predictor of sleep quality was SES, which increased the predictive capacity of the model (demographic and psychosocial variables) by 20% in the hierarchical analyses. The most significant predictor in the non-internally displaced group was CDI. This research indicates that displacement may affect sleep quality and psychosocial functioning. The importance of family SES as a contributing factor to displaced adolescents' poor sleep quality is highlighted. An integrated approach designed to improve the psychosocial environment of internally displaced adolescents is needed for their protection. PMID:26311481

  19. Generation of isolated ultra-short attosecond pulses by coherent control of the population of excited states

    NASA Astrophysics Data System (ADS)

    Jooya, Hossein Z.; Li, Peng-Cheng; Liao, Sheng-Lun; Chu, Shih-I.

    2016-01-01

    We present an ab-initio theoretical investigation of the enhancement of ultra-broad super-continuum harmonic spectra by coherently controlling the electron quantum paths of the helium atom and He+ ion. The time-dependent Schrödinger equation is solved by means of the time-dependent generalized pseudo-spectral method, allowing non-uniform and optimal spatial grid discretization and accurate and efficient propagation of the wave function in space and time. The population of the first two low-lying excited states of He+ is selectively controlled by adding low intensity, high frequency laser pulses to a two color mid-infrared laser field. Although the intensity of the added field is weak, its high frequency makes the subsequent ionization probability from excited states become much larger than for the case of many photons (mid-IR filed), even though the intensity is smaller. We found that the intensity of the attosecond pulse generated by superposing a range of synchronized high harmonics is significantly enhanced by 20 orders of magnitude. Similar calculations have been performed for the neutral He atoms. We found that an intense and ultra-short isolated 18 as can be generated directly. To understand the underlying mechanism of such dramatic enhancement and the role of electron quantum paths, we perform wavelet time-frequency transform of high harmonic spectra. The results show that we can selectively control the domination of the two distinct long and short electron trajectories by controlling the population of different excited states.

  20. Measuring social class differences in cancer patient survival: is it necessary to control for social class differences in general population mortality? A Finnish population-based study

    PubMed Central

    Dickman, P. W.; Auvinen, A.; Voutilainen, E. T.; Hakulinen, T.

    1998-01-01

    STUDY OBJECTIVES: Estimation of cancer patient survival by social class has been performed using observed, corrected (cause specific), and relative (with expected survival based on the national population) survival rates. Each of these measures are potentially biased and the optimal method is to calculate relative survival rates using social class specific death rates to estimate expected survival. This study determined the degree to which the choice of survival measure affects the estimation of social class differences in cancer patient survival. SETTING AND PARTICIPANTS: All Finnish residents diagnosed with at least one of 10 common malignant neoplasms during the period 1977-1985 were identified from the Finnish Cancer Registry and followed up for deaths to the end of 1992. DESIGN: Survival rates were calculated by site, sex, and age at 5, 10, and 15 years subsequent to diagnosis for each of three measures of survival; relative survival, corrected (cause specific) survival, and relative survival adjusted for social class differences in general mortality. Regression models were fitted to each set of rates for the first five years of follow up. MAIN RESULTS: The degree of variation in relative survival resulting from social class decreased, althou