Probe Ca2+/Camodulin reguation of membrane proteins engineering

Calmodulin (CaM) is a eukaryotic Ca2+ signaling protein which can interact with more than 300 enzymes in the cell including membrane proteins Ryanodine receptor1 (RyR1) and gap junction protein connexin 43 (Cx43). By binding to Ca2+, CaM undergoes a conformational change which exposed the hydrophobic patch that access to the target protein. wt-CaM and three mutant CaM (isolate C and N domain of CaM, deletion of five residues from the central linker of CaM) are designed for studying the specific contributions to calcium binding affinity and calcium induced conformational change. wt-CaM exhibits metal binding affinity to calcium analog Tb3+ with a Kd of 3.97 nM using FRET assay and metal-buffer system and activates target protein phosphodiesterase assay. The Kd values of domain specific calcium binding affinity of CaM probed by intrinsic Phe or Tyr are 12.2 and 2.77 uM, respectively. In addition, Ca2+ also induces helicity for both w.t. CaM and C-terminal domain variant. Further, conditions such as medium and Glucose amount for isotopic labeling of CaM by 15N, 13C and D2O have been optimized with relatively high yield of hetero-isotopic labeled CaM. This prepared us to probe the detailed interaction of CaM and its target protein and calcium induced conformational change by high resolution NMR. Furthermore, RyR1 mini domain, which contains two CaM binding regions of RyR1 was designed to study the binding mode of the two regions with CaM. Obtaining bacterial expressed and purified RyR1 mini domain was achieved by engineered with a His-Tag which overcomes the insoluble issue that occurred in the initial study of expression and purification with a GST tag. Moreover, to probe the interaction of CaM to the cytosolic loop of Cx43 that contains two putative CaM binding sites as well as the role of transmembrane region of Cx43, we have successfully expressed and purified fragments Cx4388-154 and Cx4399-154 as a His-tag protein encompassing regions 88-154 and 99-154 of Cx43 with predicted CaM binding sites with and without additional transmembrane region from Cx43. Both fragments were obtained with high yield after expressed as inclusion body and His-tag purification. Fragment Cx4388-154 was shown to bind dansylated CaM with a Kd of 0.107 μM using florescence spectroscopy

Imaginatorium for children with visual impairment

Although accessible city planning and architecture codes, such as the ADA standards, have significantly improved the lives of people with disabilities by providing physical access to infrastructure, individuals with visual impairments, particularly blind children, still face significant obstacles to fully engage in social activities. Blind children are a vulnerable group that encounters various challenges in developing their cognitive and motor skills, as well as accessing education and social opportunities. In order to gain a deeper understanding of the factors in spatial design that impact blind people’s spatial perception, this thesis conducted a review of existing architectural approaches and proposes a set of principles that can enhance the environment’s friendliness towards individuals with visual impairments. These principles include considerations for general layout, surface materials, sound, light, color, smell, and signage. This thesis focuses on the Providence Children’s Museum as the site for creating an “imaginatorium” - a playful and imaginative space designed for all children, especially the blind. Through the use of materials, lighting, and child-scale design, the imaginatorium encourages blind children to actively engage with the environment using their other senses, promoting their imagination and socialization skills. The imaginatorium is designed to be a safe and welcoming space for blind children, providing them with opportunities to explore and interact with their surroundings. By creating such a space, this thesis aims to promote greater awareness and understanding of the challenges faced by visually impaired children, and to encourage people of all abilities to consider the needs and experiences of this vulnerable group

Joint radar-communication waveform designs using signals from multiplexed users

Joint radar-communication designs are exploited in applications where radar and communications systems share the same frequency band or when both radar sensing and information communication functions are required in the same system. Finding a waveform that is suitable for both radar and communication is challenging due to the difference between radar and communication operations. In this paper, we propose a new method of designing dual-functional waveforms for both radar and communication using signals from multiplexed communications users. Specifically, signals from different communications users multiplexed in the time, code or frequency domains across different data bits are linearly combined to generate an overall radar waveform. Three typical radar waveforms are considered. The coefficients of the linear combination are optimized to minimize the mean squared error with or without a constraint on the signal-to-noise ratio (SNR) for the communications signals. Numerical results show that the optimization without SNR constraint can almost perfectly approximate the radar waveform in all the cases considered, giving good dual-functional waveforms for both radar and communication. Also, among different multiplexing techniques, time division multiple access is the best option to approximate the radar waveform, followed by code division multiple access and orthogonal frequency division multiple access

What Roles does Emotional Intelligence Play in Leadership?

This study focuses on the relationship between Emotional Intelligence (EI) and leadership. The main study is related to how EI influences leadership in both positive and negative ways. The study explores the definition of EI, and how EI influences leadership behaviors which includes how the four factors of EI affect Katz’ Three Skills. The study also discusses how EI affects leadership behaviors and outcomes positively and negatively. EI plays an important role in leadership, and the study explains that EI significantly facilitates leaders to be effective leaders if they are able to balance both positive and negative influences of EI. Most articles study the positive side of EI, though some articles explain the negative side of EI. However, an effective leader needs to obtain the abilities to balance both sides of EI in leadership. For further discussion in the future, a question to consider is how can leaders keep a suitable balance of these positive and negative aspects of EI in leadership? A video recording of this presentation is available here

Space of ambience : learning the relationship between environment, emotion, and behavior

I feel like I live life as two different people: one at school, and another at home, and I’m constantly trying to figure out why I feel this way. One of my undergraduate instructors said that he feels I am hiding myself in school, which I hadn’t thought about until he said this to me. I am more social in life, but act introverted in school. I don\u27t want to be attentioned in some context but I want to understand the meaning behind it. This project is a design process for mirroring people in spaces. Mirrors are bridges to connect my inner world and the outer world. When I stare in a mirror, I feel strange. It seems to bring together different parts of me, my fear, my bravery. Reflecting myself there opens up a space for me to focus and explore the space between my feelings and surroundings. I often act in a very controlled way in my everyday life, so when I show up in different spaces, people only see what I want them to see. Mirrors help me realize that my emotional side is not always visible in how I show myself to others. For example, I would dress up when I am in a fine dining restaurant, but that doesn’t mean I do not want to wear comfortable clothes. But of course, mirrors are not all the same, so my experience with them also shifts. Plane mirrors reflect only a portion of their surroundings and are bound by their own edges. In contrast, curved mirrors have the power to reflect my entire surroundings instead of just a segment of them. Curved mirrors create a moment, a space, for me to stare at the relationship between my human emotion, my behavior, and the environment I relate with. The experience of reflecting in the curved mirror is exciting. My body and surroundings squeezed, merging me in the surroundings and magnifying how I sense space. Those mirrors frame all the components in the environment, and I can see their relationship with my behaviors and feelings in space. With that in mind, I decided to experiment. I took a mirrored ball, went to different spaces, took photos, and recorded observations of how I felt and the components of those environments that generated strong emotion. I walked through cafe shops, streets, conference rooms, etc, and stayed for a while to experience myself in space. I found several things. For instance, I noticed that my body\u27s movements changed based on my emotions, and my emotions changed regarding my environment. So then, space impacts the way I use and express my body. Due to their exclusivity, curved mirrors became a research tool. They are objects I use as a medium to really see myself in space. By mapping my experiences in space, I understood that the way I experience architecture goes beyond the physical. Analyzing the relationship between my emotions, behaviors, and surroundings let me understand that we are all components of the environment and that together we create ambiances. My project proposes creating architectures that go beyond the object and can be designed as ambiances that embrace the relationship between emotions, behaviors, and environments. I decided to use the collection of my experiences as data to build a system that works as design tools for me and others. Usually, designers make spaces based on their single narrative experience of understanding. However, in this project, I want to use people\u27s emotional awareness to turn it into a method to design spaces that prioritize users and not designers. This design process then aims to embrace people\u27s emotions, and behaviors in space by exploring their representations of the environment they inhabit, which are emotionally tinged based on their internal feelings that show up in spatial explorations and behaviors. Through engaging with individuals and the sphere ball in interviews, I want to collect people\u27s experiences and seek the components of the surrounding environments that affect their emotions and behaviors. I want to appreciate the relationships between people and space and transform the mapping system as a tool into the main source to design a space, focusing on the human emotional experience. I propose creating a space using the collective data of interviewers, which lets users feel approached or avoided based on the attraction and distraction of feeling. Space responds to the user\u27s emotions by reflecting his/her own preference. This design process aims to create a space beyond helping architects understand how to design concerned about human emotions, behavior, and the environment. It can also support people to become aware of the ambiances they create and are part of by releasing their emotions, completing a self-learning process to learn what environment setting they prefer and how to connect and express their emotions in space

Time allocation for integrated bi-static radar and communication systems

Integrated radar and communications systems are increasingly important for applications requiring both sensing and information exchange. In this letter, we study the time allocation problem for an integrated bi-static radar and communications system. A closed-form expression for the achievable rate considering radar detection accuracy is derived analytically for this problem and optimized. Numerical results reveal that the optimum time allocation is characterized by the signal-to-noise ratio and the prior probability of target

Complex population history affects admixture analyses in nine-spined sticklebacks

Introgressive hybridization is an important process in evolution but challenging to identify, undermining the efforts to understand its role and significance. On the contrary, many analytical methods assume direct descent from a single common ancestor, and admixture among populations can violate their assumptions and lead to seriously biased results. A detailed analysis of 888 whole-genome sequences of nine-spined sticklebacks (Pungitius pungitius) revealed a complex pattern of population ancestry involving multiple waves of gene flow and introgression across northern Europe. The two recognized lineages were found to have drastically different histories, and their secondary contact zone was wider than anticipated, displaying a smooth gradient of foreign ancestry with some curious deviations from the expected pattern. Interestingly, the freshwater isolates provided peeks into the past and helped to understand the intermediate states of evolutionary processes. Our analyses and findings paint a detailed picture of the complex colonization history of northern Europe and provide backdrop against which introgression and its role in evolution can be investigated. However, they also expose the challenges in analyses of admixed populations and demonstrate how hidden admixture and colonization history misleads the estimation of admixture proportions and population split times.Peer reviewe