42 research outputs found
Learning Arithmetic Formulas in the Presence of Noise: A General Framework and Applications to Unsupervised Learning
No full textWe present a general framework for designing efficient algorithms for unsupervised learning problems, such as mixtures of Gaussians and subspace clustering. Our framework is based on a meta algorithm that learns arithmetic formulas in the presence of noise, using lower bounds. This builds upon the recent work of Garg, Kayal and Saha (FOCS '20), who designed such a framework for learning arithmetic formulas without any noise. A key ingredient of our meta algorithm is an efficient algorithm for a novel problem called Robust Vector Space Decomposition. We show that our meta algorithm works well when certain matrices have sufficiently large smallest non-zero singular values. We conjecture that this condition holds for smoothed instances of our problems, and thus our framework would yield efficient algorithms for these problems in the smoothed setting
Jarnail and Pritam
No full textThis is the story of Jarnail and Pritam (fictionalized characters) who make new roles for themselves without turning to substances to cope. It is, however, still a story that is familiar to anyone who works with immigrant seniors. There is an increased awareness in BC of the needs of an aging population, and more specifically, the unique needs of senior ethnocultural populations. Awareness is a good start, but more attention and resources are needed to help immigrant seniors, so their stories will turn out as well as Jarnail and Pritam’s.Not peer reviewedethnic diversity; senior services; immigrant services; alcohol abuse; South Asian British Columbian
Learning Arithmetic Formulas in the Presence of Noise: A General Framework and Applications to Unsupervised Learning
No full textWe present a general framework for designing efficient algorithms for
unsupervised learning problems, such as mixtures of Gaussians and subspace
clustering. Our framework is based on a meta algorithm that learns arithmetic
circuits in the presence of noise, using lower bounds. This builds upon the
recent work of Garg, Kayal and Saha (FOCS 20), who designed such a framework
for learning arithmetic circuits without any noise. A key ingredient of our
meta algorithm is an efficient algorithm for a novel problem called Robust
Vector Space Decomposition. We show that our meta algorithm works well when
certain matrices have sufficiently large smallest non-zero singular values. We
conjecture that this condition holds for smoothed instances of our problems,
and thus our framework would yield efficient algorithms for these problems in
the smoothed setting.Comment: 85 pages, comments welcom
PP-405: A NOVEL REGENERATIVE APPROACH FOR ANDROGENETIC ALOPECIA THROUGH MITOCHONDRIAL PYRUVATE CARRIER INHIBITION AND HAIR FOLLICLE STEM CELL REACTIVATION—A COMPREHENSIVE REVIEW
No full textAndrogenetic alopecia (AGA) affects over 80% of men and 50% of women, driven by hair follicle stem cell (HFSC) dysfunction and follicular miniaturization. Regenerative approaches that directly reactivate dormant HFSCs offer promise beyond supportive treatments. To critically appraise PP-405, a first-in-class topical mitochondrial pyruvate carrier (MPC) inhibitor, evaluating its mechanism, preclinical validation, and early clinical efficacy and safety in AGA. A systematic review was conducted analyzing peer-reviewed literature, clinical trial data, and regulatory submissions related to PP-405 and mitochondrial pyruvate carrier inhibition in hair follicle biology. PP-405 operates through mitochondrial pyruvate carrier (MPC) inhibition, redirecting cellular metabolism toward lactate production and subsequently activating dormant hair follicle stem cells. Phase 1 clinical trials demonstrated safety, target engagement, and statistically significant stem cell activation. Phase 2a trials involving 78 participants showed that 31% of men with advanced hair loss achieved greater than 20% hair density increase at 8 weeks, compared to 0% in the placebo group. No systemic absorption was detected, indicating localized scalp activity. PP-405 inhibits MPC protein complexes, preventing pyruvate entry into mitochondria and forcing cytoplasmic lactate production via lactate dehydrogenase upregulation. This metabolic shift triggers an integrated stress response mediated by the ATF4 transcription factor, ultimately reactivating quiescent hair follicle stem cells and promoting anagen phase entry. PP-405 represents a paradigm shift by targeting HFSC metabolism to regenerate hair follicles rather than merely halting loss. Early clinical data indicate rapid, robust efficacy and an excellent safety profile. Ongoing Phase 2b and planned Phase 3 trials (2026) will clarify durability of response and long-term safety, supporting potential regulatory approval in 2027–2028
Applications of weak attraction theory in Out(Fn)
No full textGiven a finite rank free group FN of rank ≥ 3 and two exponentially growing outer automorphisms ψ and φ with dual lamination pairs Λ± ψ and Λ± φ associated to them, which satisfy a notion of independence described in this paper, we will use the pingpong techniques developed by Handel and Mosher [14] to show that there exists an integer M > 0, such that for every m, n ≥ M, the group GM = hψ m, φn i will be a free group of rank two and every element of this free group which is not conjugate to a power of the generators will be fully irreducible and hyperbolic. We will also look at a different proof of the theorem of Kapovich and Lustig in [18] which shows that the Cannon-Thurston map for a fully-irreducible hyperbolic automorphism exists and is finiteto-one.Ph.D.Includes bibliographical referencesIncludes vitaby Pritam Ghos
Erratum to “Practice variation in anastomotic leak after esophagectomy:Unravelling differences in failure to rescue (vol 49, pg 974, 2023)
No full textThe publisher regrets that when the article was published the following collaboration authors from the “TENTACLE – Esophagus collaborative group” appeared incorrectly in the main author list due to a technical error: Writing Committee, Joos Heisterkamp, Fatih Polat, Jeroen Schouten, Pritam Singh, Study collaborators. This has now been corrected. The publisher would like to apologise for any inconvenience caused
Erratum to “Practice variation in anastomotic leak after esophagectomy: Unravelling differences in failure to rescue” [Eur J Surg Oncol 49 (5) (May 2023) 974–982](S074879832300032X)(10.1016/j.ejso.2023.01.010)
No full text\ua9 2023 The Author(s)The publisher regrets that when the article was published the following collaboration authors from the “TENTACLE – Esophagus collaborative group” appeared incorrectly in the main author list due to a technical error: Writing Committee, Joos Heisterkamp, Fatih Polat, Jeroen Schouten, Pritam Singh, Study collaborators. This has now been corrected. The publisher would like to apologise for any inconvenience caused
Erratum to “Practice variation in anastomotic leak after esophagectomy: Unravelling differences in failure to rescue”:[Eur J Surg Oncol 49 (5) (May 2023) 974–982](S074879832300032X)(10.1016/j.ejso.2023.01.010)
No full textThe publisher regrets that when the article was published the following collaboration authors from the “TENTACLE – Esophagus collaborative group” appeared incorrectly in the main author list due to a technical error: Writing Committee, Joos Heisterkamp, Fatih Polat, Jeroen Schouten, Pritam Singh, Study collaborators. This has now been corrected. The publisher would like to apologise for any inconvenience caused.</p
Erratum to “Practice variation in anastomotic leak after esophagectomy: Unravelling differences in failure to rescue” [Eur J Surg Oncol 49 (5) (May 2023) 974–982](S074879832300032X)(10.1016/j.ejso.2023.01.010)
No full textThe publisher regrets that when the article was published the following collaboration authors from the “TENTACLE – Esophagus collaborative group” appeared incorrectly in the main author list due to a technical error: Writing Committee, Joos Heisterkamp, Fatih Polat, Jeroen Schouten, Pritam Singh, Study collaborators. This has now been corrected. The publisher would like to apologise for any inconvenience caused
