Do Firms Learn by Exporting or Learn to Export? Evidence from Small and Medium-Sized Enterprises (SMEs) in Swedish Manufacturing

Using a matching approach, we compare the productivity trajectories of future exporters and matched and unmatched non-exporters. Future exporters have higher productivity than do unmatched non-exporters before entry into the export market, which indicates self-selection into exports. More interestingly, we also find a productivity increase among future exporters relative to matched non-exporters 1-2 years before export entry. However, the productivity gap between future exporters and matched non-exporters does not continue to grow after export entry. Our results suggest that learning-to-export occurs but that learning-by-exporting does not. In contrast to previous studies on Swedish manufacturing, we focus particularly on small and medium-sized enterprises (SMEs)productivity; learning-to-export; learning-by-exporting; matching

Jobs and Exposure to International Trade within the Service Sector in Sweden

The service sector is very heterogeneous with respect to internationalization; in some industries there is international trade (or it may potentially exist), whereas other industries are non-tradable. Data on international trade in services is, however, typically very limited, making it difficult to identify in which industries there are international trade. In this paper, we partially surmount the problems with insufficient service trade statistics by calculating locational Ginis for different industries in the private business sector as well as in the public sector. The basic idea is that from the regional concentration of different activities within a country one can identify industries where there appears to be regional trade, and hence also a potential for international trade. Based on our method we find that the number of employed in tradable service appears to be at least as large as in the manufacturing sector. Remarkably, a larger share of the skilled labor exposed to international trade is working in the service sector than in manufacturing, while a majority of the less skilled labor working in tradable industries is employed in manufacturing. When it comes to employment growth, we observe that the employment has increased in tradable service, while it has fallen in the manufacturing sector (the whole sector is regarded as tradable).jobs; service trade; regional concentration; structural change

Do Firms Learn by Exporting or Learn to Export? Evidence from Small and Medium-Sized Enterprises (SMEs) in Swedish Manufacturing

Using a matching approach, we compare the productivity trajectories of future exporters and matched and unmatched non-exporters. Future exporters have higher productivity than do unmatched non-exporters before entry into the export market, which indicates self-selection into exports. More interestingly, we also find a productivity increase among future exporters relative to matched non-exporters 1-2 years before export entry. However, the productivity gap between future exporters and matched non-exporters does not continue to grow after export entry. Our results suggest that learning-to-export occurs but that learning-by-exporting does not. In contrast to previous studies on Swedish manufacturing, we focus particularly on small and medium-sized enterprises (SMEs).productivity; learning-to-export; learning-by-exporting; matching

Jobs and Exposure to International Trade within the Service Sector in Sweden

The service sector is very heterogeneous with respect to internationalization; in some industries there is international trade (or it may potentially exist), whereas other industries are non-tradable. Data on international trade in services is, however, typically very limited, making it difficult to identify in which industries there are international trade. In this paper, we partially surmount the problems with insufficient service trade statistics by calculating locational Ginis for different industries in the private business sector as well as in the public sector. The basic idea is that from the regional concentration of different activities within a country one can identify industries where there appears to be regional trade, and hence also a potential for international trade. Based on our method we find that the number of employed in tradable service appears to be at least as large as in the manufacturing sector. Remarkably, a larger share of the skilled labor exposed to international trade is working in the service sector than in manufacturing, while a majority of the less skilled labor working in tradable industries is employed in manufacturing. When it comes to employment growth, we observe that the employment has increased in tradable service, while it has fallen in the manufacturing sector (the whole sector is regarded as tradable).jobs; service trade; regional concentration; structural change

SZZ Unleashed: An Open Implementation of the SZZ Algorithm -- Featuring Example Usage in a Study of Just-in-Time Bug Prediction for the Jenkins Project

Numerous empirical software engineering studies rely on detailed information about bugs. While issue trackers often contain information about when bugs were fixed, details about when they were introduced to the system are often absent. As a remedy, researchers often rely on the SZZ algorithm as a heuristic approach to identify bug-introducing software changes. Unfortunately, as reported in a recent systematic literature review, few researchers have made their SZZ implementations publicly available. Consequently, there is a risk that research effort is wasted as new projects based on SZZ output need to initially reimplement the approach. Furthermore, there is a risk that newly developed (closed source) SZZ implementations have not been properly tested, thus conducting research based on their output might introduce threats to validity. We present SZZ Unleashed, an open implementation of the SZZ algorithm for git repositories. This paper describes our implementation along with a usage example for the Jenkins project, and conclude with an illustrative study on just-in-time bug prediction. We hope to continue evolving SZZ Unleashed on GitHub, and warmly invite the community to contribute

Smells like home: Desert ants, Cataglyphis fortis, use olfactory landmarks to pinpoint the nest

<p>Abstract</p> <p>Background</p> <p><it>Cataglyphis fortis </it>ants forage individually for dead arthropods in the inhospitable salt-pans of Tunisia. Locating the inconspicuous nest after a foraging run of more than 100 meters demands a remarkable orientation capability. As a result of high temperatures and the unpredictable distribution of food, <it>Cataglyphis </it>ants do not lay pheromone trails. Instead, path integration is the fundamental system of long-distance navigation. This system constantly informs a foraging ant about its position relative to the nest. In addition, the ants rely on visual landmarks as geocentric navigational cues to finally pinpoint the nest entrance.</p> <p>Results</p> <p>Apart from the visual cues within the ants' habitat, we found potential olfactory landmark information with different odour blends coupled to various ground structures. Here we show that <it>Cataglyphis </it>ants can use olfactory information in order to locate their nest entrance. Ants were trained to associate their nest entrance with a single odour. In a test situation, they focused their nest search on the position of the training odour but not on the positions of non-training odours. When trained to a single odour, the ants were able to recognise this odour within a mixture of four odours.</p> <p>Conclusion</p> <p>The uniform salt-pans become less homogenous if one takes olfactory landmarks into account. As <it>Cataglyphis </it>ants associate environmental odours with the nest entrance they can be said to use olfactory landmarks in the vicinity of the nest for homing.</p

Flexible weighing of olfactory and vector information in the desert ant Cataglyphis fortis

Desert ants, Cataglyphis fortis, are equipped with remarkable skills that enable them to navigate efficiently. When travelling between the nest and a previously visited feeding site, they perform path integration (PI), but pinpoint the nest or feeder by following odour plumes. Homing ants respond to nest plumes only when the path integrator indicates that they are near home. This is crucial, as homing ants often pass through plumes emanating from foreign nests and do not discriminate between the plume of their own and that of a foreign nest, but should absolutely avoid entering a wrong nest. Their behaviour towards food odours differs greatly. Here, we show that in ants on the way to food, olfactory information outweighs PI information. Although PI guides ants back to a learned feeder, the ants respond to food odours independently of whether or not they are close to the learned feeding site. This ability is beneficial, as new food sources—unlike foreign nests—never pose a threat but enable ants to shorten distances travelled while foraging. While it has been shown that navigating C. fortis ants rely strongly on PI, we report here that the ants retained the necessary flexibility in the use of PI

Spatial Representation of Odorant Valence in an Insect Brain

SummaryBrains have to decide whether and how to respond to detected stimuli based on complex sensory input. The vinegar fly Drosophila melanogaster evaluates food sources based on olfactory cues. Here, we performed a behavioral screen using the vinegar fly and established the innate valence of 110 odorants. Our analysis of neuronal activation patterns evoked by attractive and aversive odorants suggests that even though the identity of odorants is coded by the set of activated receptors, the main representation of odorant valence is formed at the output level of the antennal lobe. The topographic clustering within the antennal lobe of valence-specific output neurons resembles a corresponding domain in the olfactory bulb of mice. The basal anatomical structure of the olfactory circuit between insects and vertebrates is known to be similar; our study suggests that the representation of odorant valence is as well

β-Adrenoceptor activation depresses brain inflammation and is neuroprotective in lipopolysaccharide-induced sensitization to oxygen-glucose deprivation in organotypic hippocampal slices

<p>Abstract</p> <p>Background</p> <p>Inflammation acting in synergy with brain ischemia aggravates perinatal ischemic brain damage. The sensitizing effect of pro-inflammatory exposure prior to hypoxia is dependent on signaling by TNF-α through TNF receptor (TNFR) 1. Adrenoceptor (AR) activation is known to modulate the immune response and synaptic transmission. The possible protective effect of <inline-formula><m:math xmlns:m="http://www.w3.org/1998/Math/MathML" name="1742-2094-7-94-i1"><m:mover accent="true"><m:mi>α</m:mi><m:mo>˜</m:mo></m:mover></m:math></inline-formula> and <inline-formula><m:math xmlns:m="http://www.w3.org/1998/Math/MathML" name="1742-2094-7-94-i2"><m:mover accent="true"><m:mi>β</m:mi><m:mo>˜</m:mo></m:mover></m:math></inline-formula>AR activation against neuronal damage caused by tissue ischemia and inflammation, acting in concert, was evaluated in murine hippocampal organotypic slices treated with lipopolysaccharide (LPS) and subsequently subjected to oxygen-glucose deprivation (OGD).</p> <p>Method</p> <p>Hippocampal slices from mice were obtained at P6, and were grown <it>in vitro </it>for 9 days on nitrocellulose membranes. Slices were treated with β1(dobutamine)-, β2(terbutaline)-, α1(phenylephrine)- and α2(clonidine)-AR agonists (5 and 50 μM, respectively) during LPS (1 μg/mL, 24 h) -exposure followed by exposure to OGD (15 min) in a hypoxic chamber. Cell death in the slice CA1 region was assessed by propidium iodide staining of dead cells.</p> <p>Results</p> <p>Exposure to LPS + OGD caused extensive cell death from 4 up to 48 h after reoxygenation. Co-incubation with β1-agonist (50 μM) during LPS exposure before OGD conferred complete protection from cell death (P < 0.001) whereas the β2-agonist (50 μM) was partially protective (p < 0.01). Phenylephrine was weakly protective while no protection was attained by clonidine. Exposure to both β1- and β2-agonist during LPS exposure decreased the levels of secreted TNF-α, IL-6 and monocyte chemoattractant protein-1 and prevented microglia activation in the slices. Dobutamine remained neuroprotective in slices exposed to pure OGD as well as in TNFR1^-/-and TNFR2^-/-slices exposed to LPS followed by OGD.</p> <p>Conclusions</p> <p>Our data demonstrate that activation of both β1- and β2-receptors is neuroprotective and may offer mechanistic insights valuable for development of neuro-protective strategies in neonates.</p