Recoverable Robust Shortest Path Problems

Recoverable robustness is a concept to avoid over-conservatism in robust optimization by allowing a limited recovery after the full data is revealed

The Maximum Capacity of a Line Plan is Inapproximable

We consider a basic subproblem which arises in line planning with upper capacities: How much can be routed maximally along all possible lines? The essence of this problem is the Path Constrained Network Flow (PCN) problem. We explore the complexity of this problem. In particular we show that it is as hard to approximate as MAX CLIQUE. We also show that the PCN problem is hard for special graph classes, interesting both from a complexity and from a practical perspective. Finally, we present a relevant graph class for which there is a polynomial-time algorithm

Workforce capacity to address obesity: a Western Australian cross-sectional study identifies the gap between health priority and human resources needed

Background: The disease burden due to poor nutrition, physical inactivity and obesity is high and increasing. An adequately sized and skilled workforce is required to respond to this issue. This study describes the public health nutrition and physical activity (NAPA) practice priorities and explores health managers and practitioner’s beliefs regarding workforce capacity to deliver on these priorities. Methods: A workforce audit was conducted including a telephone survey of all managers and a postal survey of practitioners working in the area of NAPA promotion in Western Australia in 2004. Managers gave their perspective on workforce priorities, current competencies and future needs, with a 70 % response rate. Practitioners reported on public health workforce priorities, qualifications and needs, with a 56 % response rate. Results: The top practice priorities for managers were diabetes (35 %), alcohol and other drugs (33 %), and cardiovascular disease (27 %). Obesity (19 %), poor nutrition (15 %) and inadequate physical activity (10 %) were of lower priority. For nutrition, managers identified lack of staff (60.4 %), organisational and management factors (39.5 %) and insufficient financial resources (30.2 %) as the major barriers to adequate service delivery. For physical activity services, insufficient financial resources (41.7 %) and staffing (35.4 %) and a lack of specific physical activity service specifications (25.0 %) were the main barriers. Practitioners identified inadequate staffing as the main barrier to service delivery for nutrition (42.3 %) and physical activity (23.3 %). Ideally, managers said they required 152 % more specialist nutritionists in the workforce and 131 % specialists for physical activity services to meet health outcomes in addition to other generalist staff. Conclusion: Human and financial resources and organisational factors were the main barriers to meeting obesity, and public health nutrition and physical activity outcomes. Services were being delivered by generalists rather than specialists, which may reduce service effectiveness. Although conclusions from this research need to take into account the fact that the audit was conducted in 2004, the findings suggest that there was a need to equip health services with an adequately skilled workforce of sufficient capacity to deliver an effective public health response to the obesity epidemic, particularly addressing poor nutrition and physical inactivity

Bullying escolar: um fenômeno multifacetado

School bullying can involve children in different ways, making them play different roles, among them, victims, bullies and bully-victims. The aim of this study was to describe how bullying occurs in high social vulnerability schools of Florianópolis metropolitan area and the roles played by students in this phenomenon. Overall, 409 children and adolescents from the 3rd to 5th grades and of two public elementary schools aged 8-16 years (X = 11.14) participated in this study. As a tool, the Olweus Questionnaire adapted to the Brazilian population was used. For data analysis, descriptive statistics and inferential statistics were applied by the Mann Whitney and Kruskal Wallis tests. As for results, 29.8% of boys and 40.5% of girls reported being victims; 32.3% of boys and 24.6% of girls reported being bullies. Victims were the most willing to help a colleague who is suffering from bullying (X = 1.54; p> 0.001), even if they do not know the victims (X = 1.57; p> 0.004). Bullies are differentiated from the group that does not participate (X = 1.73) and the group of victims (X = 2.34), being those who felt less alone (x = 1.47; p> 0.001). It was concluded that the information obtained in this study is indispensable in the search for alternatives to reduce school bullying. The strengthening of relations between school and students and a better preparation of teachers and school staff are extremely necessary to try to minimize the effects of risk factors to which these children are exposed and consequently violence at school.O bullying escolar pode envolver crianças de diferentes maneiras, fazendo com que essas assumam papéis diferenciados. Dentre estes, têm-se vítimas, agressores e vítimas-agressoras. O objetivo deste estudo foi descrever como ocorre o bullying em escolas de alta vulnerabilidade social da Grande Florianópolis e os papéis assumidos pelos alunos nesse fenômeno. Quanto ao método, participaram 409 crianças e adolescentes do terceiro ao quinto ano e da quarta à sexta série do ensino fundamental, de duas escolas públicas municipais, com idades entre 8 e 16 anos (X=11,14). Como instrumento, utilizou-se o Questionário de Olweus adaptado à população brasileira. Para a análise dos dados, empregaram-se a estatística descritiva e estatística inferencial por meio dos testes Mann Whitney e Kruskal Wallis. Quanto aos resultados, 29,8% dos meninos e 40,5% das meninas relataram terem sido vítimas; já 32,3% dos meninos e 24,6% das meninas relataram terem sido agressores. As vítimas foram as que se mostraram mais dispostas a ajudar como podem um colega que esteja sofrendo agressão (X=1,54; p>0,001), mesmo que não o conheçam (X=1,57; p>0,004). Em contrapartida, os agressores se diferenciaram do grupo que não participa (X=1,73) e do grupo das vítimas (X=2,34), sendo aqueles que menos se sentiram sozinhos (X=1,47; p>0,001). Concluiu-se que as informações obtidas neste estudo são indispensáveis na busca de alternativas para redução do bullying escolar. O fortalecimento das relações entre escola e alunos, e um maior preparo dos professores e funcionários são extremamente necessários para tentar minimizar os efeitos dos fatores de risco a que essas crianças estão expostas e consequentemente a violência na escola.CAPES - Proc. nº 0815/14-4CIEC - Centro de Investigação em Estudos da Criança, IE, UMinho (UI 317 da FCT)Projeto Estratégico da FCT: UID/CED/00317/201

Gene Expression of Stromelysin and Aggrecan in Osteoarthritic Cartilage

Objective: To analyze cartilage gene expression of patients with osteoarthritis (OA) in correlation with radiographic and histological findings. Materials and Methods: Twenty-one patients with OA of the knee admitted for total knee replacement were analyzed clinically and radiographically by the Kellgren and Lawrence system. During surgery, cartilage samples from the medial and lateral condyles and tibial plateaus were harvested separately. Specimens were analyzed histologically (Mankin score) and total RNA was extracted directly from cartilage tissue. Steady state levels of stromelysin (MMP-3), aggrecan (AGG) and the house-keeping gene β-actin were measured using quantitative PCR. Results: Histology of medial and lateral knee compartments corresponded to radiographic changes (Spearman correlation coefficient: r = 0.7 (p < 0.01)). There was a positive correlation between MMP-3 and AGG gene expression (r = 0.4; p < 0.01). We found considerable variation of expression levels of MMP-3 and AGG and no correlation of gene expression with histological or radiographic scoring. Conclusion: The positive correlation between AGG and MMP-3 suggests a common regulation of anabolic and catabolic metabolism. There was no simple dependency between gene expression and histological and radiological findings in cartilage.Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich