2,290 research outputs found
Deaths Exceed Births in Most of Europe, But Not in the United States
In this brief, authors Kenneth Johnson, Layton Fields, and Dudley Poston, Jr. present important new findings about the diminishing number of births compared to deaths in Europe and the United States from their recent article in Population and Development Review. Their research focuses on the prevalence and dynamics of natural decrease in subareas of Europe and the United States in the first decade of the twenty-first century using counties (United States) or county-equivalents (Europe). The authors report that 58 percent of the 1,391 counties of Europe had more deaths than births during that period compared to just 28 percent of the 3,137 U.S. counties. Natural decrease is more widespread in Europe because its population is older, fertility rates are lower, and there are fewer women of child-bearing age. Natural decrease is a major policy concern because it drains the demographic resilience from a region, diminishing its economic viability and competitiveness. The implications of the recent European immigrant surge for natural decrease are uncertain, but the authors’ analysis suggests that natural decrease is likely to remain widespread in Europe for the foreseeable future
Development and evaluation of a novel orally administered subunit vaccine to control foodborne pathogens
Development of vaccines for effective control of foodborne pathogens and infection represents an important development in reducing public health risk. Advancements in the area of biotechnology have increased innovative potential and allow new technologies to be used as a promising control strategy for alternatives to antibiotics. We have been working to create a novel vaccine platform that incorporates a subunit/epitope sequence, common for all E. coli strains (broad spectrum), into an inactivated orally administered vaccine platform that protects against infection and disease by inducing mucosal immunity
A national register for surveillance of inherited disorders: beta thalassaemia in the United Kingdom
OBJECTIVE: To demonstrate the value of a national register for surveillance of services for an inherited disorder. METHODS: Data from the United Kingdom Thalassaemia Register and the United Kingdom Register of Prenatal Diagnosis for Haemoglobin Disorders were combined in a database; these registers include all fetuses known to have been diagnosed with beta thalassaemia major, beta thalassaemia intermedia, or haemoglobin E/beta thalassaemia in the United Kingdom. Data were extracted to show outcomes (selective abortion or live birth) of all fetuses and the status of those born with a disorder (alive, dead, successful bone marrow transplant, or lost to follow-up) by parents' region of residence and ethnicity. FINDINGS: At the end of 1999 the register included 1074 patients, 807 of whom were alive and residing in the United Kingdom. A successful bone marrow transplant has been performed for 117 out of 581 (20%) patients born since 1975. Residents of Pakistani origin are now the main group at risk in the United Kingdom, replacing residents of Cypriot origin. This has led to a marked shift in the need for services from the south-east of England to the Midlands and the north of England. Despite the acceptability of prenatal diagnosis, the proportion of affected births remains 50% higher than would be expected, reflecting a widespread failure to deliver timely screening and counselling to carriers. Even though effective treatment is available the annual number of deaths is rising, indicating that better tolerated treatments are needed. CONCLUSION: A national diagnosis register is a powerful instrument for monitoring the treatment and prevention of inherited disorders and for highlighting correctable shortcomings. In view of the increasing possibilities for genetic screening there is a strong case for central funding for such databases within modern health services
Heterogeneity in a spontaneous mouse lung carcinoma: selection and characterisation of stable metastatic variants.
The development and characterisation of a new epithelial model for the experimental investigation of metastasis is described. A tissue culture cell line CMT64 was established from a spontaneous alveolar lung carcinoma of a 17 month old female C57BL/ICRF at mouse (Franks et al., 1976). Subcutaneous inoculation of cells produces local tumours which give rise to a small number of lung metastases within three weeks. Four different tissue culture sublines CMT167, 170, 175 and 181 with increased metastatic ability were selected from pooled lung metastases by culture, mouse inoculation and reselection from lung metastases through four culture/inoculation cycles. These sublines are themselves heterogeneous and clones derived from them display marked differences in metastatic behaviour. Both CMT64 and its sublines have remained relatively stable in morphology and behavior since their origin, are fairly well differentiated, produce basal lamina even in metastases, and metastasise rapidly and preferentially to the lung after subcutaneous and intravenous inoculation in both syngeneic C57 and Nu/Nu mice (Franks & Layton, 1984). The expression of the metastatic potential of these cells is strongly influenced by the age and immune status of the host. The CMT64 system is a particularly useful model for experimental metastasis studies
Ultrastructural tumour differentiation and organ specificity in high and low metastatic lines from a mouse lung carcinoma.
A tissue culture cell line CMT64 was established from a spontaneous alveolar lung carcinoma of a C57BL female mouse (Franks et al., 1976). Subcutaneous inoculation of these cells produced a local tumour and a small number of lung metastases. Four sublines CMT167, 170, 175 and 181 with increased metastatic ability were selected, as described in the accompanying paper (Layton & Franks, 1984). The tissue culture cells and the tumours produced by all the lines are well differentiated and produce laminated surfactant-like bodies as well as basal lamina, even in metastases. No ultrastructural differences were found that might correlate with metastatic behaviour in vivo. Metastases, after subcutaneous inoculation and tumour colonies after intravenous inoculation of all cell lines are only found in the lung, but after inoculation of cells into the arterial system via the left ventricle of the heart, extravascular tumour colonies were found in many organs
Assessing Repetitive Negative Thinking Using Categorical and Transdiagnostic Approaches: A Comparison and Validation of Three Polish Language Adaptations of Self-Report Questionnaires
Repetitive negative thinking (RNT) is a transdiagnostic process involved in the risk, maintenance, and relapse of serious conditions including mood disorders, anxiety, eating disorders, and addictions. Processing mode theory provides a theoretical model to assess, research, and treat RNT using a transdiagnostic approach. Clinical researchers also often employ categorical approaches to RNT, including a focus on depressive rumination or worry, for similar purposes. Three widely used self-report questionnaires have been developed to assess these related constructs: the Ruminative Response Scale (RRS), the Perseverative Thinking Questionnaire (PTQ), and the Mini-Cambridge Exeter Repetitive Thought Scale (Mini-CERTS). Yet these scales have not previously been used in conjunction, despite useful theoretical distinctions only available in Mini-CERTS. The present validation of the methods in a Polish speaking population provides psychometric parameters estimates that contribute to current efforts to increase reliable replication of theoretical outcomes. Moreover, the following study aims to present particular characteristics and a comparison of the three methods. Although there has been some exploration of a categorical approach, the comparison of transdiagnostic methods is still lacking. These methods are particularly relevant for developing and evaluating theoretically based interventions like concreteness training, an emerging field of increasing interest, which can be used to address the maladaptive processing mode in RNT that can lead to depression and other disorders. Furthermore, the translation of these measures enables the examination of possible cross-cultural structural differences that may lead to important theoretical progress in the measurement and classification of RNT. The results support the theoretical hypothesis. As expected, the dimensions of brooding, general repetitive negative thinking, as well as abstract analytical thinking, can all be classified as unconstructive repetitive thinking. The particular characteristics of each scale and potential practical applications in clinical and research are discussed
Analytical Study of Certain Magnetohydrodynamic-alpha Models
In this paper we present an analytical study of a subgrid scale turbulence
model of the three-dimensional magnetohydrodynamic (MHD) equations, inspired by
the Navier-Stokes-alpha (also known as the viscous Camassa-Holm equations or
the Lagrangian-averaged Navier-Stokes-alpha model). Specifically, we show the
global well-posedness and regularity of solutions of a certain MHD-alpha model
(which is a particular case of the Lagrangian averaged
magnetohydrodynamic-alpha model without enhancing the dissipation for the
magnetic field). We also introduce other subgrid scale turbulence models,
inspired by the Leray-alpha and the modified Leray-alpha models of turbulence.
Finally, we discuss the relation of the MHD-alpha model to the MHD equations by
proving a convergence theorem, that is, as the length scale alpha tends to
zero, a subsequence of solutions of the MHD-alpha equations converges to a
certain solution (a Leray-Hopf solution) of the three-dimensional MHD
equations.Comment: 26 pages, no figures, will appear in Journal of Math Physics;
corrected typos, updated reference
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Differential Disease Susceptibilities in Experimentally Reptarenavirus-Infected Boa Constrictors and Ball Pythons.
Inclusion body disease (IBD) is an infectious disease originally described in captive snakes. It has traditionally been diagnosed by the presence of large eosinophilic cytoplasmic inclusions and is associated with neurological, gastrointestinal, and lymphoproliferative disorders. Previously, we identified and established a culture system for a novel lineage of arenaviruses isolated from boa constrictors diagnosed with IBD. Although ample circumstantial evidence suggested that these viruses, now known as reptarenaviruses, cause IBD, there has been no formal demonstration of disease causality since their discovery. We therefore conducted a long-term challenge experiment to test the hypothesis that reptarenaviruses cause IBD. We infected boa constrictors and ball pythons by cardiac injection of purified virus. We monitored the progression of viral growth in tissues, blood, and environmental samples. Infection produced dramatically different disease outcomes in snakes of the two species. Ball pythons infected with Golden Gate virus (GoGV) and with another reptarenavirus displayed severe neurological signs within 2 months, and viral replication was detected only in central nervous system tissues. In contrast, GoGV-infected boa constrictors remained free of clinical signs for 2 years, despite high viral loads and the accumulation of large intracellular inclusions in multiple tissues, including the brain. Inflammation was associated with infection in ball pythons but not in boa constrictors. Thus, reptarenavirus infection produces inclusions and inclusion body disease, although inclusions per se are neither necessarily associated with nor required for disease. Although the natural distribution of reptarenaviruses has yet to be described, the different outcomes of infection may reflect differences in geographical origin.IMPORTANCE New DNA sequencing technologies have made it easier than ever to identify the sequences of microorganisms in diseased tissues, i.e., to identify organisms that appear to cause disease, but to be certain that a candidate pathogen actually causes disease, it is necessary to provide additional evidence of causality. We have done this to demonstrate that reptarenaviruses cause inclusion body disease (IBD), a serious transmissible disease of snakes. We infected boa constrictors and ball pythons with purified reptarenavirus. Ball pythons fell ill within 2 months of infection and displayed signs of neurological disease typical of IBD. In contrast, boa constrictors remained healthy over 2 years, despite high levels of virus throughout their bodies. This difference matches previous reports that pythons are more susceptible to IBD than boas and could reflect the possibility that boas are natural hosts of these viruses in the wild
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