My journey through finance and stochastics

This year, Finance and Stochastics celebrates its 25th anniversary. The journal provides a platform for the community of researchers on which they can publish their ideas and results.Publication is an outcome of research which may be conducted for a number of years before it reaches the required maturity. I find this research process to be very important. Unfortunately, it is almost impossible to decode it from reading the research publications. This special issue of Finance and Stochastics gives me an opportunity to focus on it. I am grateful I can present my personal memory of this process. Understanding why questions are asked and how the answers are found is critical.

Unraveling the kinetochore nanostructure in Schizosaccharomyces pombe using multi-color single-molecule localization microscopy

The key to ensuring proper chromosome segregation during mitosis is the kinetochore complex. This large and tightly regulated multi-protein complex links the centromeric chromatin to the microtubules attached to the spindle pole body and as such leads the segregation process. Understanding the architecture, function and regulation of this vital complex is therefore essential. However, due to its complexity and dynamics, only its individual subcomplexes could be studied in high-resolution structural detail so far.In this study we construct a nanometer-precise in situ map of the human-like regional kinetochore of Schizosaccharomyces pombe (S. pombe) using multi-color single-molecule localization microscopy (SMLM). We measure each kinetochore protein of interest (POI) in conjunction with two reference proteins, cnp1CENP-A at the centromere and sad1 at the spindle pole. This arrangement allows us to determine the cell cycle and in particularly the mitotic plane, and to visualize individual centromere regions separately. From these data, we determine protein distances within the complex using Bayesian inference, establish the stoichiometry of each POI for individual chromosomes and, consequently, build an in situ kinetochore model for S.pombe with so-far unprecedented precision. Being able to quantify the kinetochore proteins within the full in situ kinetochore structure, we provide valuable new insights in the S.pombe kinetochore architecture.

Concept of 'Central' or 'Axial' Atlantoaxial Instability

The atlantoaxial joint is the most mobile joint of the spine and is most liable to develop instability. Atlantoaxial instability can be identified on observation of facetal alignment on lateral profile imaging, telltale clinical and radiological evidence and by direct observation of instability by manual manipulation of bones during surgery. Central or axial atlantoaxial instability is when there is no abnormal increase in atlantodental interval on dynamic imaging and there is no dural or neural compression by the odontoid process. Understanding and appropriately treating central or axial atlantoaxial instability can have clinical implications.

Exercise Cuts Both Ways with ROS in Remodifying Innate and Adaptive Responses: Rewiring the Redox Mechanism of the Immune System during Exercise

Nearly all cellular functions depend on redox reactions, including those of immune cells. However, how redox reactions are rearranged to induce an immune response to the entry of pathogens into the host is a complex process. Understanding this scenario will facilitate identification of the roles of specific types of reactive oxygen species (ROS) in the immune system. Although the detrimental effect of ROS could support the innate immune system, the adaptive immune system also requires a low level of ROS in order to stimulate various molecular functions. The requirements and functions of ROS vary in different cells, including immune cells. Thus, it is difficult to understand the specific ROS types and their targeting functions. Incomplete transfer of electrons to a specific target, along with failure of the antioxidant response, could result in oxidative-damage-related diseases, and oxidative damage is a common phenomenon in most immune disorders. Exercise is a noninvasive means of regulating ROS levels and antioxidant responses. Several studies have shown that exercise alone boosts immune functions independent of redox reactions. Here, we summarize how ROS target various signaling pathways of the immune system and its functions, along with the possible role of exercise in interfering with immune system signaling.

Automation at Truveil: Business Process Understanding and Analysis in RPA Implementation

In the process of automation implementation, it is critical for management and employees to have skills in understanding, identifying, and documenting the relevant business processes. To equip students with these skills, we employ an authentic business scenario from the Truveil, a toy company. In 2021, Truveil (a pseudonym) had operations in more than 15 countries. In this teaching case, we explain the business process of the company's Singapore office. This case provides students with the opportunity to map a business process before and after automation, understand the challenges the company faced in implementing automation, and apply critical thinking to business process automation.

Underlying factors that influence the acceptance of COVID-19 vaccine in a country with a high vaccination rate

Control of the COVID-19 pandemic largely depends on the effectiveness of the vaccination. Several factors including vaccine hesitancy can affect the vaccination process. Understanding the factors that underlie the willingness to accept vaccination brings pivotal information to control the pandemic. We analyzed the association between the willingness level to accept the COVID-19 vaccine, and vaccine determinants amidst the Chilean vaccination process. Individual-level survey data was collected from nationally representative samples of 744 respondents, and multivariate regression models used to estimate the association between outcome and explanatory variables. Trust in the COVID-19 vaccine, scientists, and medical professionals were found to increase the willingness to: accept the vaccine, a booster dose, annual vaccination, and children vaccination. Our results are critical to understanding the acceptance of COVID-19 vaccines in the context of a country with one of the highest vaccination rates in the world. We provide information for decision-making, policy design and communication of vaccination programs.

Cell Wall Fracture Mechanism in Ultrasonic Assisted Cutting of Honeycomb Materials

Revealing the ultrasonic cutting mechanism of honeycomb composite is important for determining the acoustic parameters of the ultrasonic system and selecting the parameters of the cutting process. Understanding more details of the stress on the cell wall from ultrasonic vibrating tool and the conditions for cell wall breakage is essential to study the machining mechanism. According to the evolution of contact state between the straight edge cutter and the honeycomb cell wall in a cycle, the cutting force acting on the cell wall is divided into three stages: transverse cutting load action, longitudinal cutting load action, and no cutting load action. The cell wall deflection and stress equations under transverse cutting load were established by applying elastic thin plate small deflection theory. The deformation and fracture characteristics of the honeycomb cell wall were analyzed by combining the analytical and the finite element model. The results showed that the ultrasonic vibration of the cutter greatly improved the stiffening effect of the cell wall and its fracture was caused by the deflection under the transverse cutting load, which exceeded the maximum allowable deformation after local stiffening. In addition, with only longitudinal cutting load, it was difficult to break the critical buckling state that leads to cell wall fracture.