Lunch with Leaders: Influence Extraordinary Authentic Women in STEM Careers for Empowerment

Marsha Evans, LPC-S: How to Lead in STEM Without Losing Your Hair or Your Sleep - 048

High-achieving women in STEM are burning out because they are honoring invisible childhood "contracts" that reward overwork, but true leadership requires reconnecting with the body to rip up those old agreements and build a sustainable identity. In this episode of Lunch with Leaders, host Adaeze Iloeje-Udeogalanya [⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://www.linkedin.com/in/adaeze-iloeje-udeogalanya⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠] (TEDx speaker and leadership strategist) sits down with Marsha Evans LPC-S [https://www.linkedin.com/in/marshaevanslpc/], a therapist who blends traditional cognitive behavioral therapy with holistic modalities like Reiki, sound healing, and VR technology. They tackle a critical issue for women in STEM and leadership: the hidden cost of the “hustle contract.” Adaeze opens up about her previous mindset of wanting to outsource her entire life to give 150%, realizing that never lying down unless sick was a badge of honor—but a dangerous one. Marsha reframes this drive as a “contract” signed in childhood, often rooted in family systems where overworking was normalized. The conversation reveals why high-achieving women burn out: not because they are weak, but because they are rewarded for over-giving until their bodies intervene. Key insights include the biological reality of the 90-second emotion rule, why autoimmune diseases and weight retention are often the body “keeping score” of disconnected living, and the simplicity of reconnecting with your “little you” to find your true identity. Marsha introduces practical, trauma-informed strategies for leaders to date their bodies, track their baselines, and build a wellness team with the same rigor they build a boardroom strategy. The episode concludes that healing isn’t lying down—it is the ultimate leadership strategy for sustainable impact. Marsha Instagram: https://www.instagram.com/marshalistens/ [https://www.instagram.com/marshalistens/] Marsha's Website: https://marshalistens.com [https://marshalistens.com ] FAQs 1. Why do high achievers often get autoimmune diseases? According to Marsha, the body always communicates "I don't want to do this anymore," but we are trained to ignore it for dopamine hits (accolades, promotions). When we consistently override physical boundaries, the body "keeps score" resulting in inflammation, weight retention, and hair loss. To implement in your own leadership or share with your STEM audience: 1. Audit Your "Contracts": Take 15 minutes to write down three "rules" you live by (e.g., "I never lie down unless sick"). Next to each, write who taught you that (parent, teacher, culture). Ask: Does this rule serve my 2026 body? 2. Date Your Body (The Baseline): For five days, rate your chest tightness or fatigue on a scale of 1-10 (morning, noon, night). Do not judge the numbers—just collect data. Look for patterns linking high numbers to specific meetings or people. Timestamps (Key Moments) * [00:00] Introduction: The mindset of outsourcing your entire life to give 150%. * [03:15] The "Contracts" we unknowingly sign in childhood (family systems and work ethic). * [06:30] Why never lying down isn't a badge of honor—it’s a warning sign. * [08:45] The physical cost: Autoimmune diseases, hair loss, and why Black women aren't heard in medical spaces. * [12:00] Disconnection from identity: Quitting the basketball scholarship and moving to rural family land. * [15:20] The simple hack: Go back to what "little you" loved (e.g., riding bikes). * [18:45] How to track your burnout baseline (sleep, chest tightness, driving home feelings). * [22:10] The 90-second rule for releasing emotions vs. looping them. * [25:30] Blending tech with healing: Using VR and sound baths for deeper subconscious release. * [29:00] The one action step: Write a letter to your younger self or do one small childhood activity. * [32:15] Marsha’s legacy: Being the hand that walks you to the door so you realize you had the keys all along.

The High Cost of Moving Goalposts: Leadership Challenges for Women in STEM - 047

In this solo reflection, In this solo reflection, Adaeze Iloeje-Udeogalanya [⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://www.linkedin.com/in/adaeze-iloeje-udeogalanya⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠] addresses promotion burnout—a pervasive phenomenon where high-achieving women, especially in STEM, become disillusioned with career advancement due to systemic barriers, repeated goalpost-shifting, and lack of equitable recognition. Drawing from real stories, recent research, and personal experience, she debunks the myth of an ambition gap and instead attributes the issue to broken systems, not broken individuals. She offers actionable strategies: reassess reasons for stepping back, reject self-blame, embrace strategic relationship-building, and access supportive tools (a free leadership diagnostic and personal strategy calls). The episode encourages women to hold onto ambition, rebuild faith, and move forward with autonomy and intention. Who Is This For? This episode is for high-performing, ambitious women—especially those in STEM—who feel stuck or discouraged in their careers despite exceptional effort and commitment. It specifically addresses promotion burnout: the exhaustion and disillusionment that results when repeated hard work for advancement is met with systemic barriers and moving goalposts, rather than recognition and reward. Key Moments * [00:00:00] – Description of promotion burnout as a systemic issue, not personal failure * [00:01:40] – Reflection prompts: Have you lost ambition? Are you questioning faith in the system? * [00:02:56] – Introduction of the term "promotion burnout" + research statistics * [00:04:18] – Gallup study: Women are more engaged and motivated yet more burnt out than men * [00:06:32] – Personal story: Systematically moving goalposts for high performers * [00:08:07] – Signs of promotion burnout and its impact on ambition * [00:09:09] – What’s at stake: Losing the self that dreamed big * [00:09:39] – Research: 81% of women feel disadvantaged in promotions * [00:12:12] – New approach: Be intentional, strategic, and prioritize the right relationships * [00:14:09] – Action step: Self-assessment—why did you stop pursuing your goals? * [00:16:28] – Free leadership diagnostic and strategic support offered. FAQs Q: What is promotion burnout? A: The exhaustion and discouragement women feel after repeated efforts toward advancement are met with systemic barriers, making further attempts feel futile. Q: Is promotion burnout a personal failing? A: No. Adaeze Iloeje-Udeogalanya emphasizes it is a rational, evidence-based reaction to systems that repeatedly require women to prove themselves and then move the goalposts. Q: How can I tell if I have promotion burnout? A: Signs include not raising your hand for opportunities, dreading promotion conversations, convincing yourself you’re content with less, and feeling less motivated due to repeated disappointment. Q: What can I do if I suspect I have promotion burnout? A: Complete a self-assessment to determine if you stepped back because of personal reprioritization or systemic barriers, then seek strategic support. Q: Where can I get more support? A: Adaeze Iloeje-Udeogalanya offers a free five-minute leadership diagnostic and private authority strategy calls (links in show notes). Resources ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://www.linkedin.com/in/adaeze-iloeje-udeogalanya⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠]⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠Leadership Edge Diagnostic⁠⁠⁠⁠⁠⁠⁠⁠ [⁠https://link.africanwomeninstem.com/authorityshiftassessment⁠]⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [ ⁠https://link.africanwomeninstem.com/StrategyCall⁠] ⁠⁠⁠⁠Book a Strategy Call with ⁠⁠Adaeze Iloeje-Udeogalanya⁠⁠⁠ [ ⁠https://link.africanwomeninstem.com/StrategyCall⁠] ⁠⁠⁠⁠Follow Adaeze Iloeje-Udeogalanya on LinkedIn⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://www.linkedin.com/in/adaeze-iloeje-udeogalanya⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠] ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠Follow African Women in STEM on LinkedIn⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://www.linkedin.com/company/african-women-in-stem/⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠] ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠Follow African Women in STEM on Instagram ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [https://www.instagram.com/africanwomenin_stem/]⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [https://www.instagram.com/africanwomenin_stem/] ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠Join the African Women in STEM Membership⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://link.africanwomeninstem.com/MEMBERSHIP⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠] ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠Visit the African Women in STEM Website⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [https://africanwomeninstem.com/⁠⁠⁠⁠⁠⁠⁠] ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [https://africanwomeninstem.com] ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠Watch Adaeze Iloeje-Udeogalanya's ⁠⁠⁠⁠⁠⁠TEDX Talk⁠⁠⁠⁠⁠⁠ on YouTube⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [https://youtu.be/xYcVJJKBQrY]

Erin Treacy: Practical Advice and Strategies for New Managers - 046

This episode with Erin Treacy and Adaeze Iloeje-Udeogalanya⁠ [⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://www.linkedin.com/in/adaeze-iloeje-udeogalanya⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠]is for high-achieving professionals, leaders, and especially women in STEM who want to: * Break away from burnout and over-responsibility * Cultivate more effective, people-first leadership styles * Navigate generational dynamics at work * Help teams thrive through better communication and boundaries It’s valuable for new and seasoned leaders, business owners, HR professionals, team leads, and anyone seeking sustainable success in fast-paced environments. Key Moments & Timestamps * What High Performers Get Wrong About Leadership * Erin Tracy describes the traps of over-responsibility for high achievers 03:06 * The pitfalls of "servant leadership" done wrong: bottlenecks, frustration, and pushing good people away 04:11 * Avoiding Burnout & Setting Boundaries * Adejuda Galanya and Erin Tracy talk through community, self-awareness, and boundary-setting 05:35 * The "Post-it Note Challenge" as a practical tool for awareness and behavior change 07:13 * Generational Differences at Work * Managing four generations in a single workplace—for the first time in history 13:53 * Gen Z’s work values, boundary-setting, and what older generations could learn 15:28 * How parental expectations shape career mindsets 32:30 * Communication, Expectations & Boundaries * How to set boundaries through proactive and respectful communication rather than ultimatum 24:03 * The importance of micro-conversations for leadership pipeline, not just filling gaps in crisis 28:17 * Leadership Development Mistakes * Pitfalls of promoting without training: 80% of first-time managers fail within 2 years 36:48 * Proactive cross-training and people-first development strategies 39:00 * People-First Leadership in Practice * Shifting from task/process focus to people focus for stronger teams 49:07 * Why people-first workplaces lead to better customer and business outcomes 50:10 Frequently Asked Questions Q: What is the biggest leadership trap for high performers? A: Taking on too much, becoming a bottleneck, and disempowering others instead of helping them grow. Q: How can I become more aware of harmful leadership habits? A: Use tools like the Post-it Note Challenge to track when you default to "I'll do it," and consciously redirect tasks back to your team for growth. Q: How do generational differences affect work and leadership? A: Different generations value time, boundaries, and work-life balance differently—misunderstandings are common unless there’s open, respectful dialogue. Q: Why do so many new managers fail? A: Lack of training and support—organizations often promote high performers without helping them build people management skills. Q: What is people-first leadership? A: Centering leadership around developing, listening to, and supporting team members, rather than just focusing on processes or products. 1. Track Your "I'll Do It" Moments: Start a Post-it Note Challenge to increase self-awareness of when you take on too much. 2. Delegate and Empower Intentionally: Ask your team, “How would you solve it?” to develop their problem-solving and autonomy. 3. Practice Proactive Communication: When needing extra work or flexibility, give advance notice and show respect for personal schedules. 4. Prioritize People Over Process: Check in with team members where they work; see their challenges firsthand before making changes. 5. Commit to Micro-Conversations: Make daily small check-ins part of your routine to keep a pulse on engagement and potential leadership in your team. 6. Advocate for Leadership Training: Don’t wait for a promotion—seek out training, mentorship, or coaching to grow as a leader. For more tips and insights, connect with Erin Tracy via her socials or weekly newsletter!

The Broken Rung: Visibility and Support for Women in STEM - 045

Adaeze Iloeje-Udeogalanya [⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://www.linkedin.com/in/adaeze-iloeje-udeogalanya⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠] explores the systemic barriers that prevent women in STEM from advancing into leadership roles. Citing the 2025 McKinsey Women in the Workplace report, she highlights the "broken rung", a critical missed first step to management where only 93% of women (and 74% of women of color) are promoted for every 100 men. Adaeze actively disputes the report's suggestion of an "ambition gap," arguing instead that the root cause of this disparity is a lack of sponsorship and equal support. She also explains how women often carry an "invisible tax"—performing unrewarded, non-KPI-aligned work to hold teams together. To overcome these hurdles, she encourages listeners to stop relying on performance alone and instead focus on strategic visibility, finding sponsors, and building strong professional networks. Who is this for?  This content is designed for women in STEM—especially those who feel stuck in their careers, are repeatedly passed over for promotions, or feel their hard work goes unrecognized. It is also highly relevant for anyone looking to build leadership visibility, secure career sponsorship, and take proactive control of their professional advancement. Key Moments & Timestamps * The Visibility Problem: Adaeze opens with an anecdote about a high-performing client who was repeatedly denied promotions due to a vague lack of "executive presence" and "visibility". * The Data & The Broken Rung: She breaks down the 2025 McKinsey report, showing that women are underrepresented at every pipeline level because they are left behind at the very first managerial promotion. * The Ambition Myth: Adaeze refutes the idea that women lack ambition, noting that when women receive equal sponsorship, the promotion gap completely disappears. * The Invisible Tax: She details how women do unrecognized team-building and inclusion work that doesn't factor into official performance reviews. * The Differentiator: Shifting the focus from just "doing excellent work" to ensuring the right decision-makers know your name and your impact. FAQs * What is the "broken rung"? It refers to the missed first promotion to manager, which sets women behind early and causes the career gap to compound and widen over time. * What is the difference between a mentor and a sponsor? A mentor gives you advice and talks to you, whereas a sponsor talks about you, using their political capital to advocate for your name in rooms where decisions are made. * Why isn't hard work enough to get promoted? Your job isn't just doing the work; it is connecting your impact to the organization's priorities and ensuring the right people know about it. Leaders are differentiated by who knows them and advocates for them, not strictly by their performance. Action Steps for Listeners * Audit your network: Honestly assess your current situation to see if you have at least two actual sponsors with the influence to create real opportunities for you. * Make your impact visible: Frame your significant deliverables around outcomes leadership cares about, such as increased revenue or reduced expenses. * Share your wins: Send brief accomplishment updates to senior leaders or make well-positioned, intentional comments in meetings to actively associate your name with your impact. Resources ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://www.linkedin.com/in/adaeze-iloeje-udeogalanya⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠]⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠Leadership Edge Diagnostic⁠⁠⁠⁠⁠⁠⁠ [⁠https://link.africanwomeninstem.com/authorityshiftassessment⁠]⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [ ⁠https://link.africanwomeninstem.com/StrategyCall⁠] ⁠⁠⁠Book a Strategy Call with ⁠⁠Adaeze Iloeje-Udeogalanya⁠⁠ [ ⁠https://link.africanwomeninstem.com/StrategyCall⁠] ⁠⁠⁠Follow Adaeze Iloeje-Udeogalanya on LinkedIn⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://www.linkedin.com/in/adaeze-iloeje-udeogalanya⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠] ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠Follow African Women in STEM on LinkedIn⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://www.linkedin.com/company/african-women-in-stem/⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠] ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠Follow African Women in STEM on Instagram ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [https://www.instagram.com/africanwomenin_stem/]⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [https://www.instagram.com/africanwomenin_stem/] ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠Join the African Women in STEM Membership⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://link.africanwomeninstem.com/MEMBERSHIP⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠] ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠Visit the African Women in STEM Website⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [https://africanwomeninstem.com/⁠⁠⁠⁠⁠⁠⁠] ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [https://africanwomeninstem.com] ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠Watch Adaeze Iloeje-Udeogalanya's ⁠⁠⁠⁠⁠⁠TEDX Talk⁠⁠⁠⁠⁠⁠ on YouTube⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ [https://youtu.be/xYcVJJKBQrY]

Rich Belsky: Humanity in Leadership and Bridging the Entrepreneurial Isolation Gap

In this episode of Lunch with Leaders, Adaeze Iloeje-Udeogalanya speaks with Rich Belsky [https://www.linkedin.com/in/richard-belsky-32930211/], a five-time founder and executive coach, about the unspoken crisis of loneliness in entrepreneurship. They challenge the toxic "wartime CEO" mythology that forces leaders to hide their struggles to appease investors and teams. Rich highlights that 65% of startups fail within five years due to "human dynamics" issues, rather than business mechanics. Together, they explore practical methods for navigating high-pressure environments, emphasizing the importance of nervous system regulation, authentic communication, and building safe communities for founders. Who is this for? This conversation is designed for entrepreneurs, founders, investors, and corporate executives. It is especially valuable for high-performing leaders, including women in STEM, who are dealing with the hidden emotional tolls of leadership, such as isolation, high-stress decision-making, and burnout. Key Moments & Timestamps: * Introduction: Adaeze introduces the podcast's mission and guest Rich Belsky. * The True Cost of Leadership: Rich reveals that loneliness, not hard work, is the most shocking part of the entrepreneurial journey. * Overcoming Fear: Discussion on finding peer groups and the "Lonely at the Top" methodology for safe sharing. * The Response Gap: Rich explains how managing your nervous system between a stimulus and a response prevents destructive reactions. * The 65% Failure Rate: The staggering statistic that human dynamic issues are the leading cause of startup failure. * The Limits of AI: Why AI cannot replace the essential human empathy and lived experience required for strong leadership. * Changing the Narrative: Rich's legacy goal to separate a founder's personal identity from their company's success. FAQs * Why is loneliness so prevalent among founders? Founders often feel they cannot share their struggles with investors (for fear of losing funding) or their teams (for fear of losing trust), leaving them isolated during high-pressure situations. * What is the "Response Gap"? It is the mental and physiological space between a trigger (stimulus) and your reaction. Creating this space allows leaders to make thoughtful choices rather than reacting out of fear or high cortisol levels. * Why do so many startups fail? According to Harvard Business School research cited in the episode, 65% of startups fail in their first five years due to human dynamics issues, such as co-founder conflicts, burnout, and anxiety. * Is vulnerability a weakness in leadership? No, sharing struggles and developing a healthy leadership style is foundational for company growth and helps prevent catastrophic team rebellions or failures. Action Steps for Leaders * Build a Support Network: Find local startup groups, peer circles, or use methods like "Lonely at the Top" to connect with other founders who understand your lived experience. * Regulate Your Nervous System: Incorporate small daily practices like breathwork or a simple three-minute meditation to help you move from a reactive, head-driven state to a grounded, heart-driven state. * Foster Open Communication: Implement transparent communication systems within your team so employees feel seen, heard, and understood, which prevents resentment and cultural decay. * Seek Experienced Guidance: Reach out to mentors, organizations like the Real Mental Health Foundation, or embedded coaches to proactively work on your human dynamics.