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The purpose of this paper is to estimate the impact of one productive development program (PROPYME) in a developing nation like Costa Rica. This program seeks to increase the capacity of small and medium-sized firms (SMEs) to innovate.

Impacts have been estimated assuming that beneficiary firms are trying to maximize their profits and that PROPYME aims to increase these firms productivity. The impacts were measured in terms of three result variables real average wages employment demand and the probability of exporting. A combination of fixed effects and propensity score matching techniques was used in estimations to correct for any selection bias. The authors worked with panel data companies treated and untreated for the period 2001-2011.

PROPYME’s beneficiaries performed better than other firms in terms of labor demand and their probability of exporting. In addition, the dose and the duration of the effects of the treatment (timing effects) are important.

The authors study the impact in ways that go beyond the average treatment effects on the treated (ATT) usually estimated in the existing literature. Specifically, the research focusses on the identification of the timing or dynamic effects (i.e. how long should we wait to see results?) and treatment intensity (dosage effects).

Se estima el impacto de un programa de desarrollo productivo (Propyme) en un país en vías de desarrollo como Costa Rica. El Propyme busca incrementar la capacidad innovadora de las pequeñas y medidas empresas (pymes) costarricenses.

el impacto se ha estimado y evaluado asumiendo que las pymes beneficiaras buscan maximizar sus beneficios y que Propyme se enfoca en incrementar la productividad de esas empresas. El impacto se valoró en función de tres variables: salarios reales medios, empleo demandado y la probabilidad de exportar. Se utilizó una combinación de técnicas de efectos fijos y emparejamiento en las estimaciones con el fin de prevenir sesgos de selección. Se trabajó con un panel de datos, incluyendo empresas tratadas (beneficiarias de Propyme) así como no tratadas para el periodo 2001-2011.

los beneficiarios de Propyme tuvieron mejor desempeño que las restantes empresas en términos de empleo demandado y su posibilidad de exportar. Adicionalmente los efectos dinámicos (dosis y duración) de los tratamientos son importantes.

este artículo evalúa el impacto de una forma que va más allá de lo usual en la literatura por medio de los efectos promedios de los tratamientos sobre los beneficiarios. Esto por cuanto se enfoca en efectos dinámicos como la duración así como la intensidad.

Selective laser sintering (SLS) is a solid freeform fabrication process whereby a part is built layerwise by scanning a powder bed. The processability of metal powder varies depending on the state of the powder prior to SLS. A powder thermal pre‐treatment was developed which involved degassing the powder at an elevated temperature in a vacuum. Without powder thermal pre‐treatment, the powder may flow poorly and may “ball” or form molten clumps during the laser exposure rather than wetting into the present and previous layer. These effects result in SLS parts with poor surface finish, mechanical properties and density. The purpose of this study was to identify for titanium alloy powder the mechanisms responsible for the improvements obtained after powder thermal pre‐treatment and to optimize the thermal excursion.

The purpose of this paper is to harness the potential of microwave pre-treatment to prepare carbon from locally available Sterculia foetida fruit shells for adsorption of heavy metals, particularly Nickel ions (Ni++), from effluent.

The pre-treatment methods comprise conventional methods as sun drying and oven drying as well as high intensity microwave drying. Response surface methodology was employed to analyse the optimization of the process. The adsorption behavioural characteristics of the material were established applying adsorption isotherms.

Adsorption of Ni++ was found to be effective in microwave drying at output power of 300 W. It was observed that the maximum adsorption capacity was attained at pH 6; an adsorbent dosage of 0.25 mgml−1 and initial metal ion concentration of 20 ppm with an interactive effect of initial concentration and dosage.

The research puts emphasise on prospecting of novel biomass for carbonization and application of the same for effective adsorption. Available literature on Sterculia foetida is very limited and this work will serve to create database on the amenability of processing.

Chemical treatability of dairy wastewater originating from a dairy and dairy products plant at Istanbul was investigated on the basis of chemical oxygen demand (COD) parameter as a pre‐treatment alternative. FeCl₃, FeSO₄ and alum were used as coagulants in the jar‐test experiments of four sets of daily composite wastewater samples taken once every month. The effect of acid cracking has also been searched through acid addition and pH adjustment. Characterisation studies demonstrated that wastewater characteristics varied within a wide range in spite of no significant production changes at the plant during the experimentation period. Optimum coagulant dosage has been determined as 200mg l^–1 for all the coagulants with the optimum pH values between 4 and 4.5 for FeCl₃ and FeSO₄, and 5‐6 for alum. Maximum overall COD removal efficiencies were obtained as 72 per cent, 59 per cent and 54 per cent for FeCl₃, FeSO₄ and alum, respectively. Nevertheless, COD removal efficiencies were found to be inadequate to meet the current discharge standards of Greater Metropolitan Istanbul to sewer systems indicating that chemical treatment is insufficient for discharging chemically pre‐treated dairy wastewater to a sewage system, which was actually the main objective of the study. The results showed that the wastewater composition greatly influences the maximum removal efficiencies and also the conditions for optimum coagulation. However, attention to such chemical treatment studies on dairy wastewater has started to accelerate within the last decade in various countries of the world, such as United Arabic Emirates and Scandinavian countries where the targets of applying chemical treatment varied. In Scandinavian countries, biodegradable coagulants have been applied to use the sludge arising from the system for livestock feeding, leading to reuse of sludge. In Arabic Emirates, chemically treated dairy effluents are utilised for irrigation purposes. These recent studies point out that application of chemical treatment to dairy wastewater with various coagulants lead to a variety of utilities apart from being a pre‐treatment alternative.

Introduction The range of rapid, non‐destructive liquid cleaning systems available to industrial finishing processors as a primary means of surface pre‐treatment is continuously widening, and moreover, are also the measures being taken to automate and programme the work handling requirements of such systems. Indeed, the latest technique adopts microprocessor technology for programming the moving of baskets of components and so put an end to the manual tedium and inefficiency of moving baskets of components through a series of cleaning and finishing stages in a multi‐stage cleaning and drying plant.

The purpose of this paper is to explore whether the changes in externalising behaviour for young aggressive children differ between two evidence-based parent training (PT) programmes after treatment. The treatment formats between these programmes differ, and the authors were particularly interested in whether this influenced the results for participants with co-occurring problems (child variables such as heightened levels of attention and internalising problems, and parental variables such as marital status and education) and the consequent additional risk of poorer treatment outcomes.

A comparison of the individual treatment programme “Parent Management Training – Oregon model” (PMTO) and the group intervention programme “The Incredible Years” (IY) basic training sessions. Outcomes were explored in matched samples from two earlier Norwegian replication studies. The participants were matched on pre-treatment characteristics using a quasi-experimental mis-matching procedure.

There were no significant differences between the two interventions in parent ratings of externalising behaviours and the lack of differing effects between the two treatments remained when the co-occurring risk factors were introduced into the analyses.

The participants were matched on pre-treatment characteristics using a quasi-experimental mis-matching procedure.

A possible implication of these findings is that parents should be allowed to choose the treatment format of their preference. Further, individual PT may be more appropriate in rural settings with difficulties in forming group interventions.

Treatment effects did not differ between these two evidence-based interventions.

To the best of the knowledge independent comparisons of two evidence-based PT interventions are not previously conducted.

This research focuses on the effects of paste pre-treatment, concentration of sodium alginate, steaming conditions for colour yield and outline sharpness of ink-jet printing. The results show that (a) coating is a better method than padding for paste pre-treatment of cotton fabrics; (b) 102°C × 12min is the best condition for steaming; (c) pattern sharpness is better when the concentration of sodium alginate increases; and (d) color yield diminishes when the concentration exceeds 20g/L. In other words, when the optimum concentration of sodium alginate is 20g/L, the amount of ejected ink can reach as much as 260%. In this study, four reactive dyes (i.e. cyan, magenta, yellow and black) of different chemical constitutions were used, and the colour fastness results against washing and light reveal an acceptable rating above grade 4.

Job Corps is the United State’s largest and most comprehensive training program for disadvantaged youth aged 16–24 years old. A randomized social experiment concluded that, on average, individuals benefited from the program in the form of higher weekly earnings and employment prospects. At the same time, “young adults” (ages 20–24) realized much higher impacts relative to “adolescents” (ages 16–19). Employing recent nonparametric bounds for causal mediation, we investigate whether these two groups’ disparate effects correspond to them benefiting differentially from distinct aspects of Job Corps, with a particular focus on the attainment of a degree (GED, high school, or vocational). We find that, for young adults, the part of the total effect of Job Corps on earnings (employment) that is due to attaining a degree within the program is at most 41% (32%) of the total effect, whereas for adolescents that part can account for up to 87% (100%) of the total effect. We also find evidence that the magnitude of the part of the effect of Job Corps on the outcomes that works through components of Job Corps other than degree attainment (e.g., social skills, job placement, residential services) is likely higher for young adults than for adolescents. That those other components likely play a more important role for young adults has policy implications for more effectively servicing participants. More generally, our results illustrate how researchers can learn about particular mechanisms of an intervention.

Pre‐treatment of wastewater discharged from a potato‐chips factory was the subject of this study. Wastewater discharged from this factory is characterized by high values of BOD, TSS and oil and grease (3,685, 4,115 and 169mg/l, respectively). Treatability studies via continuous aerobic and anaerobic methods treatment have been investigated. The results obtained showed marked improvement in the quality of the treated effluent using packing material versus the upflow anaerobic sludge bed reactor (UASB) without packing. An extra removal in COD (53 per cent), BOD (61 percent), TSS (52 per cent) and oil and grease (46 per cent) was obtained. Corresponding residual values were 398mgO₂/l, 235mgO₂/l, 108mg/l and 38mg/l, respectively. Based on the laboratory results, engineering designs and economic evaluation of the different treatment systems were developed.

Pickling or salt curing is one of the major traditional processes to increase the shelf life of bitter gourd in India. No information is available about optimization of salt curing of bitter gourd and the related changes in its quality. Moreover, specific investigations are needed to evaluate individual susceptibility of fruit and vegetables to osmotic dewatering with pre-treatment to obtain new minimally processed food products. The purpose of this study is to optimize the salt curing process with blanching as pretreatment for bitter gourd.

A study was conducted to optimize the blanching and other process factors of salt curing (solution concentration and treatment time) based on mass transfer and quality factors of bitter gourd using response surface methodology. Experimental design was made using central composite rotatable design with different time of blanching, solution concentration and treatment time. The colour, firmness, water activity and other mass transfer kinetic parameters were used for optimization.

Blanching had significant effect (p < 0.001) on water loss (WL), weight reduction (WR), solid gain (SG), water activity and firmness of bitter gourd. Mass transfer kinetic parameters like WL, SG and normalized solid content increased and normalized moisture content was found to decrease with increase in solution concentration and curing time. Relationships between process variables and quality factors were established in either quadratic or linear form with higher R² values. A 15 per cent solution concentration for the period of 5 h with the blanched samples at 800°C for 5.26 min was found to be the optimum condition for osmotic dehydration to achieve maximum WL and SG, minimum water activity and minimum changes in firmness.

The optimized combinations for the salt curing process would be more helpful for the processors and other stakeholders involved in the pickling process by reducing energy and other input resources.

Mostly in India, the pickling process is carried out at micro- and small-scale level and in an unorganized way. This study would help those involved to reduce their input resources and to organize the process, thus leading to more dividends to the stakeholders and optimum price to the end-users. For the medium- and large-scale processing units, this study would give insight to automate the whole process in an efficient manner.

This study was performed using sophisticated and higher-end instruments. The data were observed meticulously and analysed with proper statistical tools, increasing the credibility of the study. This study gives concrete results which are directly useful to the stakeholders.