scholarly journals Environmental and population externalities

2009 ◽  
Vol 15 (1) ◽  
pp. 1-19 ◽  
Author(s):  
FRANK JÖST ◽  
MARTIN F. QUAAS

ABSTRACTWe analyze the external effects that arise in the decisions of firms on polluting emissions and in the decisions of parents on the number of births in an optimal control model with three stock variables representing population, economic capital, and pollution. We distinguish two different types of households, which represent opposite ends of a spectrum of potential familial structures: ‘dynastic households’, in which the family sticks together forever and ‘micro-households’, in which children leave their parent's household immediately after birth. We show that the decision of parents on the number of births involves an externality that is qualitatively different for both types of familial structure. Hence, population policy should be different, according to the type of household. A first best result may be obtained in the case of dynastic households if an appropriate tax on the household size is applied, or, in the case of micro-households, if an appropriate tax on children is applied.

2020 ◽  
Vol 7 (3) ◽  
pp. 200007
Author(s):  
Amandine Aftalion ◽  
Emmanuel Trélat

We introduce a new optimal control model which encompasses pace optimization and motor control effort for a runner on a fixed distance. The system couples mechanics, energetics, neural drive to an economic decision theory of cost and benefit. We find how effort is minimized to produce the best running strategy, in particular, in the bend. This allows us to discriminate between different types of tracks and estimate the discrepancy between lanes. Relating this model to the optimal path problem called the Dubins path, we are able to determine the geometry of the optimal track and estimate record times.


2016 ◽  
Vol 4 (6) ◽  
pp. 26
Author(s):  
Zaidan Ali Jassem

This paper traces the Arabic origins or cognates of the “definite articles” in English and Indo-European languages from a radical linguistic (or lexical root) theory perspective. The data comprises the definite articles in English, German, French, Spanish, Portuguese, Italian, Romanian, Latin, Greek, Macedonian, Russian, Polish, Sanskrit, Hindi, Bengali, Persian, and Arabic. The results clearly indicate that five different types of such articles emerged in the data, all of which have true Arabic cognates with the same or similar forms and meanings, whose differences are due to natural and plausible causes and different routes of linguistic change, especially lexical, semantic, or morphological shift. Therefore, the results support the adequacy of the radical linguistic theory according to which, unlike the Family Tree Model or Comparative Method, Arabic, English, German, French, Latin, Greek, and Sanskrit not only belong to the same language family, renamed Eurabian or Urban family, but also are dialects of the same language, with Arabic being their origin all because only it shares the whole cognates with them all and because it has a huge phonetic, morphological, grammatical, and lexical variety. They also manifest fundamental flaws and grave drawbacks which plague English and Indo-European lexicography for ignoring Arabic as an ultimate ancestor and progenitor not only in the treatment of the topic at hand but in all others in general. On a more general level, they also show that there is a radical language from which all human languages stemmed and which has been preserved almost intact in Arabic, thus being the most conservative and productive language


2021 ◽  
Vol 18 (1) ◽  
Author(s):  
He-Teng Zhang ◽  
Hao Wang ◽  
Hai-Sheng Wu ◽  
Jian Zeng ◽  
Yan Yang

Abstract Background Although some studies have investigated the bacterial community in vaginal tract of pregnant women, there are few reports about the viral community (virome) in this type of microenvironment. Methods To investigate the composition of virome in vaginal secretion samples, 40 vaginal secretion samples from pregnant women with vaginitis and 20 vaginal secretion samples from pregnant women without vaginitis, pooled into 4 and 2 sample pools, respectively, were subjected to viral metagenomic analysis. Results Results indicated virus sequences showing similarity to human papillomavirus (HPV), anellovirus, and norovirus were recovered from this cohort of pregnant women. Further analysis indicated that 15 different defined types and one unclassified type of HPV were detected from pregnant women with vaginitis while only 3 defined types of HPV were detected in pregnant women without vaginitis. Five different groups of viruses from the family Anelloviridae were present in pregnant women with but none of them were detected in pregnant women without vaginitis. Norovirus was detected in 3 out of the 4 sample pools from pregnant women with vaginitis but none in the pregnant women without vaginitis. Twelve complete genomes belonging to 10 different types of HPV, and 5 novel anllovirus genomes belonging 2 different genera in Anelloviridae were acquired from these libraries, based on which phylogenetical analysis and pairwise sequence comparison were performed. Phageome in these samples was also briefly characterized and compared between two groups. Conclusion Our data suggested that virome might play an important role in the progression of vaginitis in pregnant women.


2020 ◽  
Vol 32 (S1) ◽  
pp. 147-147
Author(s):  
Conceição Balsinha ◽  
Steve Iliffe ◽  
Sónia Dias ◽  
Manuel Gonçalves-Pereira

INTRODUCTION: Primary care visits of persons with dementia involve different types of communication, bringing together the patient, the family carer and the general practitioner (GP). A particular challenge is the necessary involvement of a third person (the carer) in patient-doctor encounters (or the patient in carer-doctor encounters, as dementia advances). These triad dynamics should be better understood, as health outcomes are expected to result from or be mediated by them.OBJECTIVE: Our aim is to explore triadic dynamics in Portuguese primary care consultations with persons with dementia, their family carers and GPs.METHODS: This is the first part of an ongoing project (Dementia in Primary Care: the Patient, the Carer and the Doctor in the Medical Encounter - Bayer Investigation Grant | NOVAsaúde Ageing 2018). Consultations with persons with dementia, their carers and GPs (purposive sampling) are audio-recorded, transcribed verbatim and thematically analysed. We report the analysis of interactions of the first six consultations, using NVIVO® software.RESULTS: The most frequent type of interaction was between GPs and carers, followed by interactions involving the whole triad. The patients who had more recent relationships with their GPs tended to participate less, irrespective of the stage of dementia. Carers were the ones most often initiating triadic interactions, and GPs the ones most often terminating them by directly addressing the patients. Doctor-carers interactions were very sparse in some consultations.DISCUSSION AND CONCLUSION: These preliminary findings suggest that doctor-patient interactions may be limited in a number of GPs’ consultations, seemingly compromising patient-centred approaches. Nevertheless, even when GPs were involved in triadic interactions they often tried to address the patient directly. We are looking forward to complete this part of the project: to our knowledge, there is practically no evidence from live-recorded primary care consultations about these triadic dynamics.


2009 ◽  
Vol 24 (S1) ◽  
pp. 1-1
Author(s):  
J. Wancata ◽  
M. Freidl ◽  
F. Friedrich ◽  
T. Matschnig ◽  
A. Unger ◽  
...  

Aims:The purpose of this study was to investigate disability among patients suffering from schizophrenia and to identify predictors of disability.Methods:101 patients from different types of psychiatric services in Vienna and diagnosed with schizophrenia according to ICD-10 were included. They were investigates by means of 36-Item self-administered version of the WHO Disability Assessment Schedule II (WHO-DAS-II) and the PANSS-scale. Patients’ mothers and fathers were asked to fill in the Family Problem Questionnaire.Results:The mean total score of the WHO-DAS-II was 74.1 (SD 21.9). When using weighted sub-scores the highest disability scores were found for social contacts, participation in society and household (means 2.58, 2.57 and 2.51 respectively). Using logistic regression, overall disability was positively associated with patient's age, overall severity of symptoms (PANSS) and number of previous hospital admissions. Overall disability was not associated with duration of illness and or patient's gender. The subjective burden experienced by patients’ fathers and mothers were increased by reduced social contacts and impaired participation in society, while we could not find an association with other domains of patient's disability (understanding, mobility, self-care, household).Conclusions:This study shows that schizophrenia results in disability in several domains. Family caregivers’ burden was predominantly increased by social consequences of schizophrenia.


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