Impact of mobile app user acquisition on managerial decisions: Evidence from empirical experiment

In this research we conducted a mixed research, using qualitative and quantitative analysis to study the relationship and impact between mobile advertisement and mobile app user acquisition and the conclusions companies can derive from it. Data was gathered from management of mobile advertisement campaigns of a portfolio of three different mobile apps. We found that a number of implications can be extracted from this intersection, namely to product development, internationalisation and management of marketing budget. We propose further research on alternative app users sources, impact of revenue on apps and exploitation of product segments: wearable technology and Internet of Things.

"Managing the impact of tourism in historic urban destinations. A sustainability approach: Case study of Sintra"

In this Work Project, it will be assessed how Sintra’s sustainability is affected by the consequences of the visitor flow on its urban historical center. Two research questions will support this case study: What is the main problem affecting Sintra as a tourism destination? How sustainable will Sintra be in the next 10-15 years? The main findings suggest Sintra faces an intense seasonal pressure on its historical city center and its sustainability might be seriously affected in the near future, whereby three domains of the destination deserve a serious strategy reassessment: promotion, management, and supply.

“The impact of online ratings on video game sales”

Online third-party reviews have been grown over the last decade and they now play an important role as a tool for helping customers evaluate products and services that in many cases offer more than tangible features. This study intends to quantify the impact online ratings have over video game sales by conducting a linear regression analysis on 300 titles for the previous console generation (PlayStation® 3 and Xbox® 360) using a data from the video game industry to understand the existing influence on this particular market. The findings showed that these variables have a weak linear relationship thus suggesting that quality of a title explains little the commercial success of a video game and instead this should cover a wider range of factors. Afterwards, we compare results to previous ones and discuss the managerial implications for upcoming gaming generations.

The impact of online promotional efforts on customer acquisitiom and retention at continente.pt

Continente Online (COL) is the market leader of online grocery retailing in Portugal. Aiming at sustaining this position, it has been focusing its promotional efforts in acquiring and retaining customers. This report intakes an extensive study on the impact of COL’s exclusive promotional efforts (free delivery offers and ten percent discounts on loyalty card) on customer acquisition and retention, as well as, a cost analysis on these offers. Two econometric models were developed and the results were interesting. It was concluded that free delivery offers have a significant impact both in terms of customer acquisition and retention, having also a lower cost in comparison with ten percent on loyalty card discounts.

Impact of the IL-18 gene polymorphism in response to antiviral therapy in chronic HCV genotype 4 patients

^a Introduction Interleukin (IL)-18 is a well-known major proinflammatory cytokine with broad biological effects. The major immunomodulatory functions of IL-18 include enhancing T cell and natural killer cell cytotoxicity. Serum levels of this cytokine were shown to increase in chronic hepatitis C patients compared to non-infected healthy people. An association between IL-18 gene promoter polymorphisms and pegylated interferon (PEG-IFN) and ribavirin treatment outcomes has been reported for individuals with chronic hepatitis C virus genotype 1 (HCV-1). In this study, HCV genotype 4 (HCV-4) patients were assessed for IL-18 gene polymorphisms and treatment outcomes or severity of liver disease because data concerning the impact of IL-18 gene polymorphisms on patients with HCV-4 infections are limited. Methods This study included 123 chronic HCV-4 Egyptian patients and 123 apparently healthy volunteer blood donors who served as a control group. HCV genotyping was performed using the line probe assay. IL-18 genotyping was performed using the TaqMan Real-Time PCR method in all 246 patient and control samples. Results In our study, all patients had HCV-4. IL-18 gene single nucleotide polymorphism (SNP) (-607C/A) genotype distributions and allele frequencies did not differ between HCV patients and normal healthy subjects or between patient groups when compared according to the therapeutic response. Moreover, the presence of an IL-18 SNP was not associated with histological disease severity. We conclude that the presence of the IL-18 SNP rs1946518 does not affect the outcome of chronic HCV-4 treatment in Egyptian patients. Conclusions The IL-18 SNP rs1946518 does not affect response to treatment in chronic HCV-4 patients.

Impact of oral health on health-related quality of life : A cross-sectional study

Background: Despite the consensus regarding the existence of a relationship between “impacts on oral health” and “health-related quality of life”, this relationship, considering the latent nature of these variables, is still poorly investigated. Thus, we performed this study in order to determine the magnitude of the impacts of oral health, demographic and symptom/clinical variables on the health-related quality of life in a Brazilian sample of dental patients. Methods: A total of 1,007 adult subjects enrolled in the School of Dentistry of São Paulo State University (UNESP) - Araraquara Campus for dentistry care between September/2012 and April/2013, participated. 72.4 % were female. The mean age was 45.7 (SD = 12.5) years. The Oral Health Impact Profile (OHIP-14) and the Short Form Health Survey (SF-36) were used. The demographic and symptom/clinical variables collected were gender, age, economic status, presence of pain and chronic disease. The impact of studied variables on health-related quality of life were evaluated with a structural equation model, considering the factor “Health” as the central construct. The fit of the model was first analyzed by the evaluation of the goodness of fit indices (χ 2 /df ≤ 2.0, CFI and TLI ≥ 0.90 and RMSEA < 0.10) and the evaluation of the variables’ impact over health-related quality of life was based on the statistical significance of causal paths (β), evaluated by z tests, for a significance level of 5 %. Results: We observed adequate fit of the model to the data (χ 2 /df = 3.55; CFI = 0.95; TLI = 0.94; RMSEA = 0.05). The impacts on oral health explained 28.0 % of the variability of the health-related quality of life construct, while the total variance explained of the model was 39.0 %. For the demographic and symptom/clinical variables, only age, presence of pain and chronic disease showed significant impacts (p < 0.05). Conclusion: The oral health, age, presence of pain and chronic disease of individuals had significant influence on health-related quality of life.

Public perspective towards social impact of chang e lunar probe program

The present article is based on the MA thesis of Hou Bowen (Ph.D candidate) and on the presentation made at the ISA World Congress of Sociology held in Yokohama (Japan) on July 2014 at the Session on “Assessing Technologies: Global Patterns of Trust and Distrust” of RC23-Sociology of Science and Technology.

Impact of insecticide resistance on the field control of Aedes aegypti in the State of São Paulo

IntroductionThe need to control dengue transmission by means of insecticides has led to the development of resistance to most of the products used worldwide against mosquitoes. In the State of São Paulo, the Superintendência de Controle de Endemias(SUCEN) has annually monitored the susceptibility of Aedes aegypti to insecticides since 1996; since 1999, surveys were conducted in collaboration with the National Network of Laboratories (MoReNAa Network) and were coordinated by the Ministry of Health. In this study, in addition to the biological characterization of insecticide resistance in the laboratory, the impact of resistance on field control was evaluated for vector populations that showed resistance in laboratory assays.MethodsField efficacy tests with larvicides and adulticides were performed over a 13-year period, using World Health Organization protocols.ResultsData from the field tests showed a reduction in the residual effect of temephos on populations with a resistance ratio of 3. For adults, field control was less effective in populations characterized as resistant in laboratory qualitative assays, and this was confirmed using qualitative assays and field evaluation.ConclusionsOur results indicated that management of resistance development needs to be adopted when insect populations show reduced susceptibility. The use of insecticides is a self-limiting tool that needs to be applied cautiously, and dengue control requires more sustainable strategies.

Impact of the antipneumococcal conjugate vaccine on the occurrence of infectious respiratory diseases and hospitalization rates in children

INTRODUCTION: In 2010, to reduce the occurrence of serious pneumococcal disease, the Ministry of Health in Brazil incorporated the 10-valent pneumococcal vaccine in the immunization schedule of children younger than two years of age. The objective of this study was to evaluate the impact of vaccination on the incidence of infectious respiratory diseases in infants before and after the introduction of the 10-valent pneumococcal vaccine. METHODS: This cross-sectional study involved primary care and hospital networks from a city in Minas Gerais State, Brazil, between 2009 and 2012. RESULTS: A 40% reduction in the prevalence of community-acquired pneumonia (CAP) was observed after introducing the pneumococcal conjugate vaccine. Male children were 28% more likely to develop the disease. The prevalence ratio ([PR] = 1.96, 95% CI: 1.52 to 2.53, p < 0.05) suggested that not being vaccinated was associated with the occurrence of pneumonia. The prevalence of CAP was 70% lower (PR 0.30, 95% CI: 0.24 to 0.37, p<0.05) in children vaccinated as recommended compared to children with delayed vaccination, suggesting that the updated vaccine schedule improves protection. CONCLUSIONS: Immunization with the 10-valent pneumococcal vaccine appeared to reduce the number of pneumonia cases in children during the study period. Prospective studies are needed to confirm the efficacy of the vaccine against the occurrence of pneumococcal pneumonia.

Impact of carbon/nitrogen feeding strategy on polyhydroxyalkanoates production using mixed microbial cultures

Polyhydroxyalkanoates (PHA) production using mixed microbial cultures (MMC) requires a multi-stage process involving the microbial selection of PHA-storing microorganisms, typically operated in sequencing batch reactors (SBR), and an accumulation reactor. Since low-cost renewable feedstocks used as process feedstock are often nitrogen-deficient, nutrient supply in the selection stage is required to allow for microbial growth. In this context, the possibility to uncouple nitrogen supply from carbon feeding within the SBR cycle has been investigated in this study. Moreover, three different COD:N ratios (100:3.79, 100:3.03 and 100:2.43) were tested in three different runs which also allowed the study of COD:N ratio on the SBR performance. For each run, a synthetic mixture of acetic and propionic acids at an overall organic load rate of 8.5 gCOD L-1 d-1 was used as carbon feedstock, whereas ammonium sulfate was the nitrogen source in a lab-scale sequence batch reactor (SBR) with 1 L of working volume. Besides, a sludge retention time (SRT) of 1 d was used as well as a 6 h cycle length. The uncoupled feeding strategy significantly enhanced the selective pressure towards PHA-storing microorganisms, resulting in a two-fold increase in the PHA production (up to about 1.3 gCOD L-1). A high storage response was observed for the two runs with the COD:N ratios (gCOD:gN) of 100:3.79 and 100:3.03, whereas the lowest investigated nitrogen load resulted in very poor performance in terms of polymer production. In fact, strong nitrogen limitation caused fungi to grow and a very poor storage ability by microorganisms that thrived in those conditions. The COD:N ratio also affected the polymer composition, indeed the produced poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) showed a variable HV content (1-20 %, w/w) among the three runs, lessening as the COD:N increased. This clearly suggests the possibility to use the COD:N ratio as a tool for tuning polymer properties regardless the composition of the feedstock.

Impact of livestock on a mosquito community (Diptera: Culicidae) in a Brazilian tropical dry forest

AbstractINTRODUCTION: This study evaluated the effects of cattle removal on the Culicidae mosquito community structure in a tropical dry forest in Brazil.METHODS: Culicidae were collected during dry and wet seasons in cattle presence and absence between August 2008 and October 2010 and assessed using multivariate statistical models.RESULTS: Cattle removal did not significantly alter Culicidae species richness and abundance. However, alterations were noted in Culicidae community composition.CONCLUSIONS: This is the first study to evaluate the impact of cattle removal on Culicidae community structure in Brazil and demonstrates the importance of assessing ecological parameters such as community species composition.

Impact of chromossomal structure on the evolution of Schizosaccharomyces pombe undergoing Mutation Accumulation

Large chromosomal rearrangements are common in natural populations and thought to be involved in speciation events. In this project, we used experimental evolution to determine how the speed of evolution and the type of accumulated mutations depend on the ancestral chromosomal structure and genotype. We utilized two Wild Type strains and a set of genetically engineered Schizosaccharomyces pombe strains, different solely in the presence of a certain type of chromosomal variant (inversions or translocations), along with respective controls. Previous research has shown that these chromosomal variants have different fitness levels in several environments, probably due to changes in the gene expression along the genome. These strains were propagated in the laboratory at very low population sizes, in which we expect natural selection to be less efficient at purging deleterious mutations. We then measured these strains’ changes in fitness throughout this accumulation of deleterious mutations, comparing the evolutionary trajectories in the different rearrangements to understand if the chromosomal structure affected the speed of evolution. We also tested these mutations for possible epistatic effects and estimated their parameters: the number of arising deleterious mutations per generation (Ud) and each one’s mean effect (sd).

The economic impact of the event Volta a Portugal em Bicicleta 2015

This thesis is a Field Lab project requested by the organizer of the Volta a Portugal em Bicicleta 2015, Podium Events. Its purpose is to determine the economic impact of the event for the 21 host economies and Portugal as a whole. The Volta started in Viseu and ended in Lisboa, and lasted for two weeks from the 29th July until the 8th August. Results were computed by accessing data provided by the different economic agents involved in the event (spectators, attendees and organizer), through face-to-face surveys and contact via e-mail. The Volta generated a total economic impact of €76.261.876. Keywords: Cycling,

The impact of credit conditions on market liquidity – a case for European stock markets

The recent financial crisis has drawn the attention of researchers and regulators to the importance of liquidity for stock market stability and efficiency. The ability of market-makers and investors to provide liquidity is constrained by the willingness of financial institutions to supply funding capital. This paper sheds light on the liquidity linkages between the Central Bank, Monetary Financial Institutions and market-makers as crucial elements to the well-functioning of markets. Results suggest the existence of causality between credit conditions and stock market liquidity for the Eurozone between 2003 and 2015. Similar evidence is found for the UK during the post-crisis period. Keywords: stock

Impact of alcohol intoxication and withdrawal syndrome on social phobia and panic disorder in alcoholic inpatients

PURPOSE: To investigate the impact of alcohol intoxication and withdrawal on the course of social phobia and panic disorder. METHOD: A group of 41 alcoholic inpatients undergoing detoxification therapy were interviewed using the SCID-I (DSM-IV) and questions to detect fluctuations in the course of social phobia and panic disorder as a function of the different phases in alcohol dependence (intoxication, withdrawal, and lucid interval). RESULTS: Only 1 (2.4%) patient presented panic disorder throughout life, and 9 (21.9%) had panic attacks during alcohol intoxication or during the withdrawal syndrome. Sixteen (39%) alcoholic patients showed social phobia with onset prior to drug use. However, drinking eventually became unable to alleviate social phobia symptoms or worsened such symptoms in 31.2% of social-phobic patients. While patients with social phobia reported a significant improvement in psychiatric symptoms during alcohol intoxication, patients experiencing panic attacks worsened significantly during intoxication. In the withdrawal phase, patients with social phobia tended to have more and more intense phobic symptoms. CONCLUSION: Our findings indicate that the impact of alcohol intoxication is different for social phobia as compared to panic disorder, at first decreasing the social-phobic symptoms but later aggravating them. In panic disorder, the impact of intoxication by alcohol is more harmful, at least in the short term.