Xiao Dong

Using matching and regression analyses, we measure the difference in citations between articles posted to Academia.edu and other articles from similar journals, controlling for field, impact factor, and other variables. Based on a sample size of 31,216 papers, we find that a paper in a median impact factor journal uploaded to Academia.edu receives 16% more citations after one year than a similar article not available online, 51% more citations after three years, and 69% after five years. We also found that articles also posted to Academia.edu had 58% more citations than articles only posted to other online venues, such as personal and departmental home pages, after five years.

Using matching and regression analyses, we measure the difference in citations between articles posted to Academia.edu and other articles from similar journals, controlling for field, impact factor, and other variables. Based on a sample size of 31,216 papers, we find that a paper in a median impact factor journal uploaded to Academia.edu receives 16% more citations after one year than a similar article not available online, 51% more citations after three years, and 69% after five years. We also found that articles also posted to Academia.edu had 58% more citations than articles only posted to other online venues, such as personal and departmental home pages, after five years.

 In recent years, honeybee (Apis mellifera) colony losses have escalated in most parts of the world. Factors such as habitat loss and fragmentation, pesticides, pathogens, insect pests and nutritional deficiencies have all been attributed to these colony losses. The present research is the first study in the region that comprehensively examines whether the degree of landscape fragmentation affects the presence of Varroa destructor (Varroa mite), which is an ectoparasitic mite of the honeybee and the most devastating pest of honeybees. Additionally, we wanted to establish whether Varroa mite abundance influences honeybee colony strength. The research was conducted in Kenya within six sites of varying degrees of landscape fragmentation, from 2017 to 2018. Landscape fragmentation metrics were derived using fused medium resolution bi-temporal Sentinel-1 and Sentinel-2 satellite imagery and fragmentation metrics extracted. Subsequently, two radii (1 km and 2.5 km) around each apiary were selected for the analysis. Honeybee colony strength parameters and Varroa mite data were systematically collected in a total of 69 hive inspections across all the apiaries. The results demonstrated that the proportion of croplands and patch shape index of woody vegetation positively influenced Varroa mite occurrence at the 1 km radius. At the 2.5 km scale, the proportion of hedges in the landscape positively affected Varroa mite occurrence. On the other hand, Varroa mite had no influence on honeybee colony strength except for the number of cells with eggs that were negatively affected by Varroa mite. Our results suggest that Varroa mite presence has no effect on honeybee colony strength in this region and therefore synthetic Varroa mite control measures may not be recommendable or feasible. Furthermore, hive placement should carefully consider landscape structural effect as landscape fragmentation can be considered a vital propagation factor for Varroa mite.