Cross-Border Shopping: Evidence from Household Transaction Records

Cross-border shopping allows purchasing comparable goods at lower prices abroad. At the same time, it can reduce domestic consumption, sales, or tax collection. During the Covid-19 pandemic, many countries restricted cross-border movements to mitigate the virus’s spread, thereby also prohibiting cross-border shopping. I exploit the random timing of the Swiss border closure using data on 600 million customer-linked transactions from the largest Swiss retailer to identify patterns in cross-border shopping. I find that grocery expenditures temporarily increased by 10-15% in border regions. Households drive up to 70 minutes to a location across the border, but the distance decay function is non-linear and marginal costs of traveling become negligible after 40 minutes

Spatial frictions in consumption and retail competition

In this paper, we empirically quantify spatial consumption frictions and the degree of local retail competition. We exploit a unique data set including 1.5 billion daily transactions in combination with detailed characteristics of more than 3 million households. Our estimates are based on a quasi-experimental approach to estimate the causal effect of store openings. We find that a same-chain store opening in the proximity of households' residences reduces their expenditures at incumbent stores by 30% in the first month. Smaller effects for competitors suggest imperfect substitutability between retail chains. Exploiting more than 350 openings, we identify causal consumption gravity functions, which allow us to quantify spatial consumption areas. We document significant heterogeneities across regions and socio-demographic groups, indicating substantial inequalities in consumption access

Untersuchungen zur Synthese von neuen Phosphaalkinen und ihrer Reaktion mit Cyclopentadienylcobalt-Chelatkomplexen mit Phosphor-Seitenarm

[no abstract

Close-range photogrammetry and infrared imaging for non-invasive honeybee hive population assessment

16 p.Close-range photogrammetry and thermographic imaging techniques are used for the acquisition of all the data needed for the non-invasive assessment of a honeybee hive population. Temperature values complemented with precise 3D geometry generated using novel close-range photogrammetric and computer vision algorithms are used for the computation of the inner beehive temperature at each point of its surface. The methodology was validated through its application to three reference beehives with different population levels. The temperatures reached by the exterior surfaces of the hives showed a direct correlation with the population level. In addition, the knowledge of the 3D reality of the hives and the position of each temperature value allowed the positioning of the bee colonies without the need to open the hives. This way, the state of honeybee hives regarding the growth of population can be estimated without disturbing its natural development.S

Impaired hemodynamic response to mental stress in subjects with prehypertension is improved after a single bout of maximal dynamic exercise

INTRODUCTION: High blood pressure during mental stress in subjects with prehypertension is associated with blunted vasodilation in skeletal muscles, which might be improved by an acute bout of exercise. OBJECTIVE: To investigate the hemodynamic responses to mental stress before and after a bout of exercise in subjects with prehypertension. METHOD: Eighteen subjects with prehypertension and 16 with normotension underwent a mental stress test before and after a maximal cardiopulmonary exercise test on a treadmill. Blood pressure was measured by auscultation, and forearm blood flow was measured by venous occlusion plethysmography; from these measurements, the vascular conductance was calculated. RESULTS: Subjects with prehypertension had a higher mean blood pressure during mental stress (prehypertension 112±2 vs. normotension 101±3 mm Hg, p<0.05), and their vascular conductance did not increase (baseline 0.025±0.004 vs. mental stress 0.022±0.003 a.u., p.0.05). After the exercise bout, the mean blood pressure during mental stress was lower in subjects with prehypertension (before exercise 112±2 vs. after exercise 107±2 mm Hg, p<0.05), and vascular conductance increased (baseline 0.011±0.001 vs. mental stress 0.024±0.004 a.u., p<0.05). CONCLUSION: Subjects with prehypertension had elevated blood pressure and a blunted vasodilator response during mental stress, but their blood pressure was attenuated and their vasodilator response was normalized after a single bout of maximal dynamic exercise