How Software Refactoring Impacts Execution Time

Refactoring aims at improving the maintainability of source code without modifying its external behavior. Previous works proposed approaches to recommend refactoring solutions to software developers. The generation of the recommended solutions is guided by metrics acting as proxy for maintainability (e.g., number of code smells removed by the recommended solution). These approaches ignore the impact of the recommended refactorings on other non-functional requirements, such as performance, energy consumption, and so forth. Little is known about the impact of refactoring operations on non-functional requirements other than maintainability. We aim to fill this gap by presenting the largest study to date to investigate the impact of refactoring on software performance, in terms of execution time. We mined the change history of 20 systems that defined performance benchmarks in their repositories, with the goal of identifying commits in which developers implemented refactoring operations impacting code components that are exercised by the performance benchmarks. Through a quantitative and qualitative analysis, we show that refactoring operations can significantly impact the execution time. Indeed, none of the investigated refactoring types can be considered “safe” in ensuring no performance regression. Refactoring types aimed at decomposing complex code entities (e.g., Extract Class/Interface, Extract Method) have higher chances of triggering performance degradation, suggesting their careful consideration when refactoring performance-critical code.

Biochemical Properties of Two Plasmodium malariae Cysteine Proteases, Malapain-2 and Malapain-4

Cysteine proteases belonging to the falcipain (FP) family play a pivotal role in the biology of malaria parasites and have been extensively investigated as potential antimalarial drug targets. Three paralogous FP-family cysteine proteases of Plasmodium malariae, termed malapains 2–4 (MP2–4), were identified in PlasmoDB. The three MPs share similar structural properties with the FP-2/FP-3 subfamily enzymes and exhibit a close phylogenetic lineage with vivapains (VXs) and knowpains (KPs), FP orthologues of P. vivax and P. knowlesi. Recombinant MP-2 and MP-4 were produced in a bacterial expression system, and their biochemical properties were characterized. Both recombinant MP-2 and MP-4 showed enzyme activity across a broad range of pH values with an optimum activity at pH 5.0 and relative stability at neutral pHs. Similar to the FP-2/FP-3 subfamily enzymes in other Plasmodium species, recombinant MP-2 and MP-4 effectively hydrolyzed hemoglobin at acidic pHs. They also degraded erythrocyte cytoskeletal proteins, such as spectrin and band 3, at a neutral pH. These results imply that MP-2 and MP-4 are redundant hemoglobinases of P. malariae and may also participate in merozoite egression by degrading erythrocyte cytoskeletal proteins. However, compared with other FP-2/FP-3 enzymes, MP-2 showed a strong preference for arginine at the P2 position. Meanwhile, MP-4 showed a primary preference for leucine at the P2 position but a partial preference for phenylalanine. These different substrate preferences of MPs underscore careful consideration in the design of optimized inhibitors targeting the FP-family cysteine proteases of human malaria parasites.

Does Culture Matter? Measuring Cross-Country Perceptions of CSR Communication Campaigns about COVID-19

The COVID-19 pandemic has brought several challenges to businesses and societies. In response, many corporations have supported local communities and authorities in the management of the pandemic. Although these initiatives, which can be considered forms of corporate social responsibility (CSR), were highly coupled with explicit CSR communication campaigns, little is known about whether these campaigns were effective. Previous research indicates that culture can shape people’s perceptions of CSR initiatives and communications, suggesting that businesses pay attention to careful consideration of cultural norms for effective CSR communication. However, the COVID-19 pandemic as a new CSR setting may challenge earlier findings. This study empirically investigates whether three cultural factors (individualism/collectivism, uncertainty avoidance, and power distance) affect public perceptions measured as recall of and favorability towards corporate COVID-19 response initiatives across six countries. Findings from a representative survey of adults across these countries show that respondents in individualistic and collectivistic countries recall these CSR communication campaigns about these corporate COVID-19 response initiatives quite differently, and these are related to differences in power distance and uncertainty avoidance. However, no difference was found in overall corporate favorability, indicating that cultural factors did not affect levels of favorability towards such initiatives. This, we argue, can be explained by the global dimension of the COVID-19 pandemic, which is the context of these CSR initiatives. This study contributes to CSR communication literature with empirical findings from a global pandemic setting. It offers businesses and managers empirical grounds to understand the communicative impact of COVID-19 response initiatives, which can inform future CSR actions.

Radiofrequency ablation treatment of periacetabular chondrosarcoma: A case report

Needle biopsy of an incidental periacetabular bone lesion in an 18-year-old female showed a low-grade cartilaginous tumor. Based on the imaging and pelvic location, the tumor was considered a Grade I chondrosarcoma. Due to the young age, incidental discovery, and low metastatic potential, radiofrequency ablation (RFA) was recommended in favor over traditional wide en bloc resection. The patient has been radiographically and clinically stable for 2 years. RFA has not been previously reported for low-grade chondrosarcoma. Its use should be done only with careful consideration and diligent follow-up in this setting.

Recurrent amnesia caused by early seizures after hippocampal infarction: a case report

Background We report the case of a patient with recurrent episodes of disturbed memory suggestive of transient epileptic amnesia, and a focal hippocampal lesion typically associated with transient global amnesia. We argue how careful consideration of clinical, electrophysiological and imaging findings can resolve this apparent contradiction and lead to a diagnosis of early symptomatic post-stroke seizures that links brain structure to function in a new, clinically relevant way. Case presentation A 70-year-old patient was identified in clinical practice in our tertiary care centre and was evaluated clinically as well as by repeated electroencephalography and magnetic resonance imaging. The presenting complaint were recurrent episodes of short-term memory disturbance which manifested as isolated anterograde amnesia on neurocognitive evaluation. EEG and MRI revealed predominantly right frontotemporal spikes and a punctate diffusion-restricted lesion in the left hippocampus, respectively. Both symptoms and EEG changes subsided under anticonvulsant treatment with levetiracetam. Conclusions Our report contributes to the current discussion of clinical challenges in the differential diagnosis of transient memory disturbance. It suggests that focal diffusion-restricted hippocampal lesions, as seen in TGA, might be ischemic and thus highlights the importance of considering post-stroke seizures as a possible cause of transient memory disturbance.

Why Do Communities Recover Differently after Socio-Natural Disasters? Pathways to Comprehensive Success of Recovery Projects Based on Bam’s (Iran) Neighborhoods’ Perspective

Although recent studies have provided explanations for the causes of success and failure in recovery projects following socio-natural disasters, there is a need for a concise understanding of how different combinations of factors may contribute to recovery failure or success. In this study, to examine the community recovery pathways after the 2003 Bam earthquake, we conducted a fuzzy-set qualitative comparative analysis of 11 neighborhoods in Bam city and Baravat (the neighborhoods represent the division of the areas damaged by the earthquake, as presented by local government). The success of socio-natural disaster recovery projects is presented in three pathways in which the absence or presence of public engagement had a significant influence on the results. The results indicate that a recovery project should respond to the needs of the project within the continuous lifecycle of the project. Additionally, on the one hand, public participation and prompt rescue operations have a significant effect on project success. On the other hand, neglecting the needs of people and the area’s climate in housing design have led to project failure. It is expected that the findings from this study can be used to develop strategies for empowering people in recovery projects and to develop housing guidelines that respect residents’ needs while focusing on on-time and sufficient rescue processes. However, care should be taken when applying the present findings in practice, because every socio-natural disaster is unique and requires careful consideration of complex sets of features.

Digital embryos: a novel technical approach to investigate perceptual categorization in pigeons (Columba livia) using machine learning

Pigeons are classic model animals to study perceptual category learning. To achieve a deeper understanding of the cognitive mechanisms of categorization, a careful consideration of the employed stimulus material and a thorough analysis of the choice behavior is mandatory. In the present study, we combined the use of “virtual phylogenesis”, an evolutionary algorithm to generate artificial yet naturalistic stimuli termed digital embryos and a machine learning approach on the pigeons’ pecking responses to gain insight into the underlying categorization strategies of the animals. In a forced-choice procedure, pigeons learned to categorize these stimuli and transferred their knowledge successfully to novel exemplars. We used peck tracking to identify where on the stimulus the animals pecked and further investigated whether this behavior was indicative of the pigeon’s choice. Going beyond the classical analysis of the binary choice, we were able to predict the presented stimulus class based on pecking location using a k-nearest neighbor classifier, indicating that pecks are related to features of interest. By analyzing error trials with this approach, we further identified potential strategies of the pigeons to discriminate between stimulus classes. These strategies remained stable during category transfer, but differed between individuals indicating that categorization learning is not limited to a single learning strategy.

Circularity in animal production requires a change in the EAT-Lancet diet in Europe

It is not known whether dietary guidelines proposing a limited intake of animal protein are compatible with the adoption of circular food systems. Using a resource-allocation model, we compared the effects of circularity on the supply of animal-source nutrients in Europe with the nutritional requirements of the EAT-Lancet reference diet. We found the two to be compatible in terms of total animal-source proteins but not specific animal-source foods; in particular, the EAT-Lancet guidelines recommend larger quantities of poultry meat over beef and pork, while a circular food system produces mainly milk, dairy-beef and pork. Compared with the EAT-Lancet reference diet, greenhouse gas emissions were reduced by up to 31% and arable land use reduced by up to 42%. Careful consideration of the feasible substitutability between animal-source foods is needed to define potential roles of animal products in circular human diets.

Mental health assessment of Israeli adolescents before and during the COVID-19 pandemic

The measures used to contain the COVID-19 pandemic caused severe disruption to the lives of children and adolescents, compromising their mental health and wellbeing. In this study we assessed the incidence rates of psychiatric diagnoses and drugs in Israeli adolescents before and during the COVID-19 pandemic. Analysis of health records data of over 200,000 12-17 years old adolescents identified a significant increase in all mental health diagnoses and most psychiatric drugs dispensation during the COVID-19 period compared to a corresponding pre-COVID period. A gender sub-analysis revealed that most of this increase was associated with adolescent girls. Girls exhibited increases of 68% in depression, 67% in eating disorders, 42% in anxiety and 29% in stress-related diagnoses during the COVID-19 period, which are significantly higher rates than those seen in boys and in the pre-COVID period. Sector sub-analysis showed that the increase was mainly in the general Jewish sector with almost no significant increases in the Arab and ultra-orthodox sectors. Our study highlights the mental health burden of Israeli adolescents during the pandemic and suggests that careful consideration should be given to it while deciding on measures to mitigate the pandemic.