1,466 research outputs found
Peace and goodwill? Using an experimental game to analyse Paz y Desarrollo
Several decades of conflict, rebellion and unrest severely weakened civil society in parts of Colombia. Paz y Desarrollo is the umbrella term used to describe the set of locally-led initiatives that aim at addressing this problem through initiatives to promote sustainable economic development and community cohesion and action.
This project analyses the findings from a series of "public goods" games that were conducted in the spring and winter of 2006 in 103 municipalities in rural and urban Colombia with predominantly poor participants. These municipalities included both those with and without Paz y Desarrollo in place, and within those municipalities where it was ("treatment" municipalities), both individuals who are participants in the programme and those who are not. The municipalities where PYD is not in place ("control" municipalities) were surveyed as part of the evaluation of another programme - Familias en Accion (FEA), and this project also analyses the impact of this programme on game-play. The game is structured as a typical free-rider problem with the act of contributing to the "public good" (a collective money pot) being always dominated by non-contribution. We interpret contribution as an act consistent with a high degree of social capital.
We find weak evidence that the programme acts at the group level: game sessions involving programme participants have higher levels of contribution than those not involving participants. In addition, there is some evidence that intensity of the programme matters: the more participants, the larger the impact. However, there is no evidence that the programme impacts at the individual level with participants no more likely to contribute than non-participants in treatment areas
Child education and work choices in the presence of a conditional cash transfer programme in rural Colombia
This research is part of a large evaluation effort, undertaken by a consortium formed by IFS, Econometria and SEI, which has considered the effects of Familias en Accion on a variety of outcomes one year after its implementation. In early reports, we focussed on the effects of the programme on school enrolment. In this paper, we both expand those results, by carefully analysing anticipation effects along with other issues, and complement them with an analysis of child labour - both paid and unpaid (including domestic) work. The child labour analysis is made possible due to a rich time use module of the surveys that has not previously been analysed. We find that the programme increased the school participation rates of 14 to 17 year old children quite substantially, by between 5 and 7 percentage points, and had lower, but non-negligible effects on the enrolment of younger children of between 1.4 and 2.4 percentage points. In terms of work, the effects are generally largest for younger children whose participation in domestic work decreased by around 10 to 12 percentage points after the programme but whose participation in income-generating work remained largely unaffected by the programme. We also find evidence of school and work time not being fully substitutable, suggesting that some, but not all, of the increased time at school may be drawn from children's leisure time
Flapless Cone Beam Computed Tomography-Guided Implant Surgery with Contextual Transcrestal Sinus Lift Augmentation Using New Bone Compactor Tools
In the present paper, the authors present a case report of premolar edentulism in the upper jaw treated through a guided flapless oral implant surgery with contextual crestal sinus lift, performed with a system of manual screw-tapered bone expanders (B&B Dental, San Benedetto, BO, Italy). The surgery was planned by means of dedicated software, through which the data obtained from the CBCT and from intraoral scanner impression were matched, with consequent production of a surgical template. The proposed surgical procedure is minimally invasive, very simple, and fast and ensures good comfort for the patient by avoiding the elevation of mucoperiosteal flaps and uncomfortable malleting maneuvers. In addition, the presented method shows a good degree of correspondence between the ideal position of the implant in the planning phase and the actual one detectable after the surgery
A PRELIMINARY APPROACH TO ASSESS PEACH FRUIT TEXTURE BY TIME-RESOLVED SPECTROSCOPY (TRS)
Most fruits can be modeled for their internal composition as a diffusive medium at visible and near-infrared wavelengths. The low absorption in this spectral range allows exploiting VIS/NIR spectroscopic techniques to probe non-destructively the internal food properties. Time-resolved reflectance spectroscopy (TRS), in particular, allows the separate, but simultaneous estimation of absorption and scattering coefficients. Absorption and scattering properties give very different information about the medium investigated. The possibility of applying TRS to assess the texture type of peach fruit was tested. To this purpose, an instrument for TRS developed at Politecnico di Milano-Department of Physics, was exploited. At least two cultivars for each peach flesh phenotype (melting, non-melting, stony hard and slow melting) and a total of 30 fruits for each cultivar were analyzed over the spectral range 540-940 nm. The absorption spectra exhibit high values around 550 nm due to the anthocyanins' absorption features. Furthermore, an absorption peak is visible at 670 nm, linked to the chlorophyll a content and then gives an idea about the fruit ripeness (a high chlorophyll content corresponds to a less ripe fruit). With the exception of the cultivar 'Iride', particularly rich in anthocyanins, and 'Ghiaccio', anthocyaninless, the absorption spectra of all of the samples were similar. Concerning the scattering properties of peaches, by considering the equivalent density and the scatter power Mie parameters, it was possible to discriminate between three out of four texture types (melting, slow melting and stony hard). Further improvements may lead to a full discrimination in the future
Shelf life of Stracciatella cheese under modified-atmosphere packaging
The aim of this work is to evaluate the shelf life of Stracciatella cheese packaged in a protective atmosphere, using 4 different CO(2):N(2):O(2) gas mixtures [50:50:0 (M1), 95:5:0 (M2), 75:25:0 (M3), and 30:65:5 (M4) vol/vol] and stored at 8 degrees C. Cheese in traditional tubs and under vacuum were used as the controls. Results showed that the modified-atmosphere packaging, in particular M1 and M2, delayed microbial growth of spoilage bacteria, without affecting the dairy microflora, and prolonged the sensorial acceptability limit
Evaluation of temporomandibular disorders before and after orthognathic surgery: therapeutic considerations on a sample of 76 patients
Temporomandibular disorders may be associated with dental and facial malformations. The aim of this study is to record the prevalence of TMDs in patients scheduled for orthognathic surgery, reporting the development of TMDs and symptoms during the entire period of the treatment, and demonstrating the benefits of a team effort on this population.
MATERIALS AND METHODS:
Assessment of temporomandibular status was performed using the RDC/TMD criteria at T0 (prior to orthodontic therapy), T1 (3 months after the surgery), and T2 post-therapeutic cycle (6 to 12 months postoperatively). A total of 76 participants were included in the study; all the patients underwent surgical treatment: 12 had bilateral sagittal split osteotomy, 6 with condylar position devices; 64 had Le Fort I + bilateral sagittal split osteotomy, and 15 with condylar position devices. Results were evaluated with a paired-sample t-test and segmentation analysis.
RESULTS:
Forty-seven patients were affected by TMDs. At T0, 25 patients experienced TMJ pain, 27 had muscular pain, 31 suffered headaches, 42 had disc dislocation with reduction, and 5 were affected by disc dislocation without reduction. Thirty-five patients had occlusal signs of parafunctions, 8 reported tinnitus, and 7 dizziness. At T1, TMJ pain changed from 33.3% to 4.44%, muscular pain changed from 35.5% to 11.1%, headaches improved from 40% to 6.67%, and disc dislocation from 55.2% to 17.7%. Segmentation analysis highlighted improvement after therapy; 57 patients were considered recovered, 14 improved, none were considered stable, whereas 5 patients demonstrated some worsening, 3 of whom had not presented disc dislocation before surgery. At T2, 71 patients were considered completely recovered or improved.
CONCLUSIONS:
Our data indicates beyond any doubt that both functional status and pain levels related to TMDs can be significantly improved with a multi-disciplinary approach. We concluded that surgeon's intervention need to be modified in the presence of presurgical TMDs
Superconducting properties of Nb thin films deposited on porous silicon templates
Porous silicon, obtained by electrochemical etching, has been used as a
substrate for the growth of nanoperforated Nb thin films. The films, deposited
by UHV magnetron sputtering on the porous Si substrates, inherited their
structure made of holes of 5 or 10 nm diameter and of 10 to 40 nm spacing,
which provide an artificial pinning structure. The superconducting properties
were investigated by transport measurements performed in the presence of
magnetic field for different film thickness and substrates with different
interpore spacing. Perpendicular upper critical fields measurements present
peculiar features such as a change in the H_c2(T) curvature and oscillations in
the field dependence of the superconducting resistive transition width at H=1
Tesla. This field value is much higher than typical matching fields in
perforated superconductors, as a consequence of the small interpore distance.Comment: accepted for publication on Journal of Applied Physic
Welfare consequences of food prices increases: Evidence from rural Mexico
This paper presents an analysis of the welfare consequences of recent increases in food prices in Mexico using micro-level data. We estimate a QUAIDS model of demand for food, using data collected to evaluate the conditional cash transfer program Oportunidades. We show how the poor have been affected by the recent increases and changes in relative prices of foods. We also show how a conditional cash transfer program provides a means of alleviating the problem of increasing staple prices, and simulate the impact of such a policy on household welfare and consumer demand. We contrast this policy with alternative policy responses, such as price subsidies, which distort relative prices and are less well-targeted
Graphene Oxide Nanosheets Tailored With Aromatic Dipeptide Nanoassemblies for a Tuneable Interaction With Cell Membranes
Engineered graphene-based derivatives are attractive and promising candidates for nanomedicine applications because of their versatility as 2D nanomaterials. However, the safe application of these materials needs to solve the still unanswered issue of graphene nanotoxicity. In this work, we investigated the self-assembly of dityrosine peptides driven by graphene oxide (GO) and/or copper ions in the comparison with the more hydrophobic diphenylalanine dipeptide. To scrutinize the peptide aggregation process, in the absence or presence of GO and/or Cu2+, we used atomic force microscopy, circular dichroism, UV–visible, fluorescence and electron paramagnetic resonance spectroscopies. The perturbative effect by the hybrid nanomaterials made of peptide-decorated GO nanosheets on model cell membranes of supported lipid bilayers was investigated. In particular, quartz crystal microbalance with dissipation monitoring and fluorescence recovery after photobleaching techniques were used to track the changes in the viscoelastic properties and fluidity of the cell membrane, respectively. Also, cellular experiments with two model tumour cell lines at a short time of incubation, evidenced the high potential of this approach to set up versatile nanoplatforms for nanomedicine and theranostic applications
- …