356 research outputs found
Affine hom-complexes
For two general polytopal complexes the set of face-wise affine maps between
them is shown to be a polytopal complex in an algorithmic way. The resulting
algorithm for the affine hom-complex is analyzed in detail. There is also a
natural tensor product of polytopal complexes, which is the left adjoint
functor for Hom. This extends the corresponding facts from single polytopes,
systematic study of which was initiated in [6,12]. Explicit examples of
computations of the resulting structures are included. In the special case of
simplicial complexes, the affine hom-complex is a functorial subcomplex of
Kozlov's combinatorial hom-complex [14], which generalizes Lovasz' well-known
construction [15] for graphs.Comment: final version, to appear in Portugaliae Mathematic
Effect of Age at Diagnosis on Cervical Cancer Patient Prognoses in Georgia
The current incidence of cervical cancer varies around 17.0/100,000 women per year. The study aims to describe the effect of age at diagnosis on CC patient prognosis in Georgia. Methods. Univariable and Multivariable survival analysis using Coxâs regression model was constructed. All women aged â€80 years, diagnosed with invasive CC (ICD10-site code C53) from 2015 to 2019,  were eligible for inclusion in the analysis. During analysis a hazard (mortality) ratio for the patients, who were diagnosed at different ages was estimated. Survival period was determined from the date of diagnosis until the date of death or the date of last follow up visit. High risk of death was defined as a mortality of CC patients whose survival period was less than 5 years.The level of statistical significance of the study findings is estimated by using p-value andthe 95% of confidence interval (95%CI). A p value < 0.05 was considered as statistically significant. In estimation of hazard ratio, the patients under 41 years were selected as a reference group. Data was analyzed using Statistical Package of SPSS version 23. Results.Totally 1646 CC patients were enrolled in the study. The median age at diagnosis was 54years and age range was 25 - 80 years. Univariable statistical analysis has revealed that cancer diagnosed over 60 years of age had a higher death hazard (HR=1.80, p<0.001), compared to cancer detected under 60 years (HR=3.30, p<0.001). Multivariable statistical analysis has detected that stage and age at diagnosis are independent, statistically significant predictors for high mortality in patients diagnosed with cervical cancer, while the role of histological grade has not been revealed. In addition, older age generally is related to a high prevalence of comorbidities. The reasons for the unfavourable cervical cancer prognosis in older patients that was detected during statistical analysis might be explained by tumor stage at diagnoses and with higher ratesof comorbidity among the elderly. Conclusions: Finally, our study results are in concordance with numerous studies, which confirm that the age of patients at the moment of diagnosis is an independent predictor for cervical cancer early mortality
Controllability of 2D Euler and Navier-Stokes equations by degenerate forcing
We study controllability issues for the 2D Euler and Navier-
Stokes (NS) systems under periodic boundary conditions. These systems
describe motion of homogeneous ideal or viscous incompressible fluid on
a two-dimensional torus T^2. We assume the system to be controlled by
a degenerate forcing applied to fixed number of modes.
In our previous work [3, 5, 4] we studied global controllability by
means of degenerate forcing for Navier-Stokes (NS) systems with nonvanishing
viscosity (\nu > 0). Methods of dfferential geometric/Lie algebraic
control theory have been used for that study. In [3] criteria for
global controllability of nite-dimensional Galerkin approximations of
2D and 3D NS systems have been established. It is almost immediate
to see that these criteria are also valid for the Galerkin approximations
of the Euler systems. In [5, 4] we established a much more intricate suf-
cient criteria for global controllability in finite-dimensional observed
component and for L2-approximate controllability for 2D NS system.
The justication of these criteria was based on a Lyapunov-Schmidt
reduction to a finite-dimensional system. Possibility of such a reduction
rested upon the dissipativity of NS system, and hence the previous
approach can not be adapted for Euler system.
In the present contribution we improve and extend the controllability
results in several aspects: 1) we obtain a stronger sufficient condition for
controllability of 2D NS system in an observed component and for L2-
approximate controllability; 2) we prove that these criteria are valid for
the case of ideal incompressible uid (\nu = 0); 3) we study solid controllability
in projection on any finite-dimensional subspace and establish a
sufficient criterion for such controllability
Evolution of the Greater Caucasus Basement and Formation of the Main Caucasus Thrust, Georgia
Along the northern margin of the ArabiaâEurasia collision zone in the western Greater Caucasus, the Main Caucasus Thrust (MCT) juxtaposes Paleozoic crystalline basement to the north against Mesozoic metasedimentary and volcaniclastic rocks to the south. The MCT is commonly assumed to be the trace of an active plateâboundary scale structure that accommodates ArabiaâEurasia convergence, but field data supporting this interpretation are equivocal. Here we investigate the deformation history of the rocks juxtaposed across the MCT in Georgia using field observations, microstructural analysis, UâPb and 40Ar/39Ar geochronology, and 40Ar/39Ar and (UâTh)/He thermochronology. Zircon UâPb analyses show that Greater Caucasus crystalline rocks formed in the Early Paleozoic on the margin of Gondwana. Lowâpressure/temperature amphiboliteâfacies metamorphism of these metasedimentary rocks and associated plutonism likely took place during Carboniferous accretion onto the Laurussian margin, as indicated by igneous and metamorphic zircon UâPb ages of ~330â310Â Ma. 40Ar/39Ar ages of ~190â135Â Ma from muscovite in a greenschistâfacies shear zone indicate that the MCT likely developed during Mesozoic inversion and/or rifting of the Caucasus Basin. A Mesozoic 40Ar/39Ar biotite age with release spectra indicating partial resetting and Cenozoic (<40Â Ma) apatite and zircon (UâTh)/He ages imply at least ~5â8Â km of Greater Caucasus basement exhumation since ~10Â Ma in response to ArabiaâEurasia collision. Cenozoic reactivation of the MCT may have accommodated a fraction of this exhumation. However, Cenozoic zircon (UâTh)/He ages in both the hanging wall and footwall of the MCT require partitioning a substantial component of this deformation onto structures to the south.Plain Language SummaryCollisions between continents cause deformation of the Earthâs crust and the uplift of large mountain ranges like the Himalayas. Large faults often form to accommodate this deformation and may help bring rocks once buried at great depths up to the surface of the Earth. The Greater Caucasus Mountains form the northernmost part of a zone of deformation due to the ongoing collision between the Arabian and Eurasian continents. The Main Caucasus Thrust (MCT) is a fault juxtaposing old igneous and metamorphic (crystalline) rocks against younger rocks that has often been assumed to be a major means of accommodating ArabiaâEurasia collision. This study examines the history of rocks along the MCT with a combination of field work, study of microscopic deformation in rocks, and dating of rock formation and cooling. The crystalline rocks were added to the margins of presentâday Eurasia about 330â310 million years ago, and the MCT first formed about 190â135 million years ago. The MCT is likely at most one of many structures accommodating presentâday ArabiaâEurasia collision.Key PointsAmphiboliteâfacies metamorphism and plutonism in the Greater Caucasus basement took place ~330â310Â MaThe Main Caucasus Thrust formed as a greenschistâfacies shear zone during Caucasus Basin inversion and/or rifting (~190â135Â Ma)The Main Caucasus Thrust may have helped facilitate a portion of at least 5â8Â km of basement exhumation during ArabiaâEurasia collisionPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154626/1/tect21292-sup-0002-2019TC005828-ts01.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154626/2/tect21292-sup-0006-2019TC005828-ts05.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154626/3/tect21292_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154626/4/tect21292-sup-0003-2019TC005828-ts02.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154626/5/tect21292-sup-0005-2019TC005828-ts04.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154626/6/tect21292.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154626/7/tect21292-sup-0004-2019TC005828-ts03.pd
Economic Evaluation of the Hepatitis C Virus Elimination Program in the Country of Georgia, 2015 to 2017
The global campaign to eliminate HBV and HCV infection: International Viral Hepatitis Elimination Meeting and core indicators for development towards the 2030 elimination goals
Hepatitis B virus (HBV) and hepatitis C virus (HCV) affect more than 320 million people worldwide, which is more than
HIV, tuberculosis (TB) and malaria combined. Elimination of HBV and HCV will, therefore, produce substantial public
health and economic benefits and, most importantly, the prevention of 1.2 million deaths per year. In 2016, member
states of the World Health Assembly unanimously adopted a resolution declaring that viral hepatitis should be eliminated
by 2030. Currently, few countries have elimination programmes in place and even though the tools to achieve elimination
are available, the right resources, commitments and allocations are lacking. During the fifth International Viral Hepatitis
Elimination Meeting (IVHEM), 7â8 December 2018, Amsterdam, the Netherlands, an expert panel of clinicians, virologists
and public health specialists discussed the current status of viral hepatitis elimination programmes across multiple
countries, challenges in achieving elimination and the core indicators for monitoring progress, approaches that have
failed and successful elimination plans
Massive migration from the steppe is a source for Indo-European languages in Europe
We generated genome-wide data from 69 Europeans who lived between 8,000-3,000
years ago by enriching ancient DNA libraries for a target set of almost four
hundred thousand polymorphisms. Enrichment of these positions decreases the
sequencing required for genome-wide ancient DNA analysis by a median of around
250-fold, allowing us to study an order of magnitude more individuals than
previous studies and to obtain new insights about the past. We show that the
populations of western and far eastern Europe followed opposite trajectories
between 8,000-5,000 years ago. At the beginning of the Neolithic period in
Europe, ~8,000-7,000 years ago, closely related groups of early farmers
appeared in Germany, Hungary, and Spain, different from indigenous
hunter-gatherers, whereas Russia was inhabited by a distinctive population of
hunter-gatherers with high affinity to a ~24,000 year old Siberian6 . By
~6,000-5,000 years ago, a resurgence of hunter-gatherer ancestry had occurred
throughout much of Europe, but in Russia, the Yamnaya steppe herders of this
time were descended not only from the preceding eastern European
hunter-gatherers, but from a population of Near Eastern ancestry. Western and
Eastern Europe came into contact ~4,500 years ago, as the Late Neolithic Corded
Ware people from Germany traced ~3/4 of their ancestry to the Yamnaya,
documenting a massive migration into the heartland of Europe from its eastern
periphery. This steppe ancestry persisted in all sampled central Europeans
until at least ~3,000 years ago, and is ubiquitous in present-day Europeans.
These results provide support for the theory of a steppe origin of at least
some of the Indo-European languages of Europe
Human resources for health challenges of public health system reform in Georgia
<p>Abstract</p> <p>Background</p> <p>Human resources (HR) are one of the most important components determining performance of public health system. The aim of this study was to assess adequacy of HR of local public health agencies to meet the needs emerging from health care reforms in Georgia.</p> <p>Methods</p> <p>We used the Human Resources for Health Action Framework, which includes six components: HR management, policy, finance, education, partnerships and leadership. The study employed: (a) quantitative methods: from September to November 2004, 30 randomly selected district Centers of Public Health (CPH) were surveyed through face-to-face interviews with the CPH director and one public health worker randomly selected from all professional staff; and (b) qualitative methods: in November 2004, Focus Group Discussions (FGD) were held among 3 groups: a) 12 district public health professionals, b) 11 directors of district public health centers, and c) 10 policy makers at central level.</p> <p>Results</p> <p>There was an unequal distribution of public health workers across selected institutions, with lack of professionals in remote rural district centers and overstaffing in urban centers. Survey respondents disagreed or were uncertain that public health workers possess adequate skills and knowledge necessary for delivery of public health programs. FGDs shed additional light on the survey findings that there is no clear vision and plans on HR development. Limited budget, poor planning, and ignorance from the local government were mentioned as main reasons for inadequate staffing. FGD participants were concerned with lack of good training institutions and training programs, lack of adequate legislation for HR issues, and lack of necessary resources for HR development from the government.</p> <p>Conclusion</p> <p>After ten years of public health system reforms in Georgia, the public health workforce still has major problems such as irrational distribution and inadequate knowledge and skills. There is an urgent need for re-training and training programs and development of conducive policy environment with sufficient resources to address these problems and assure adequate functionality of public health programs.</p
Human resource management in the Georgian National Immunization Program: a baseline assessment
Background: Georgia's health care system underwent dramatic reform after gaining
independence in 1991. The decentralization of the health care system was one of the core elements
of health care reform but reports suggest that human resource management issues were
overlooked. The Georgian national immunization program was affected by these reforms and is not
functioning at optimum levels. This paper describes the state of human resource management
practices within the Georgian national immunization program in late 2004.
Methods: Thirty districts were selected for the study. Within these districts, 392 providers and
thirty immunization managers participated in the study. Survey questionnaires were administered
through face-to-face interviews to immunization managers and a mail survey was administered to
immunization providers. Qualitative data collection involved four focus groups. Analysis of variance
(ANOVA) and Chi-square tests were used to test for differences between groups for continuous
and categorical variables. Content analysis identified main themes within the focus groups.
Results: Weak administrative links exist between the Centres of Public Health (CPH) and Primary
Health Care (PHC) health facilities. There is a lack of clear management guidelines and only 49.6%
of all health providers had written job descriptions. A common concern among all respondents was
the extremely inadequate salary. Managers cited lack of authority and poor knowledge and skills in
human resource management. Lack of resources and infrastructure were identified as major
barriers to improving immunization.
Conclusion: Our study found that the National Immunization Program in Georgia was
characterized by weak organizational structure and processes and a lack of knowledge and skills in
management and supervision, especially at peripheral levels. The development of the skills and
processes of a well-managed workforce may help improve immunization rates, facilitate successful
implementation of remaining health care reforms and is an overall, wise investment. However,
reforms at strategic policy levels and across sectors will be necessary to address the systemic
financial and health system constraints impeding the performance of the immunization program and
the health care system as a whole
The role of supportive supervision on immunization program outcome - a randomized field trial from Georgia
<p>Abstract</p> <p>Background</p> <p>One of the most common barriers to improving immunization coverage rates is human resources and its management. In the Republic of Georgia, a country where widespread health care reforms have taken place over the last decade, an intervention was recently implemented to strengthen performance of immunization programs. A range of measures were taken to ensure that immunization managers carry out their activities effectively through direct, personal contact on a regular basis to guide, support and assist designated health care facility staff to become more competent in their immunization work. The aim of this study was to document the effects of "supportive" supervision on the performance of the immunization program at the district(s) level in Georgia.</p> <p>Methods</p> <p>A pre-post experimental research design is used for the quantitative evaluation. Data come from baseline and follow-up surveys of health care providers and immunization managers in 15 intervention and 15 control districts. These data were supplemented by focus group discussions amongst Centre of Public Health and health facility staff.</p> <p>Results</p> <p>The results of the study suggest that the intervention package resulted in a number of expected improvements. Among immunization managers, the intervention independently contributed to improved knowledge of supportive supervision, and helped remove self-perceived barriers to supportive supervision such as availability of resources to supervisors, lack of a clear format for providing supportive supervision, and lack of recognition among providers of the importance of supportive supervision. The intervention independently contributed to relative improvements in district-level service delivery outcomes such as vaccine wastage factors and the DPT-3 immunization coverage rate. The clear positive improvement in all service delivery outcomes across both the intervention and control districts can be attributed to an overall improvement in the Georgian population's access to health care.</p> <p>Conclusion</p> <p>Provider-based interventions such as supportive supervision can have independent positive effects on immunization program indicators. Thus, it is recommended to implement supportive supervision within the framework of national immunization programs in Georgia and other countries in transition with similar institutional arrangements for health services organization.</p> <p>Abstract in Russian</p> <p>See the full article online for a translation of this abstract in Russian.</p
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