Observation of long range magnetic ordering in pyrohafnate Nd2Hf2O7: A neutron diffraction study

We have investigated the physical properties of a pyrochlore hafnate Nd2Hf2O7 using ac magnetic susceptibility \chi_ac(T), dc magnetic susceptibility \chi(T), isothermal magnetization M(H) and heat capacity C_p(T) measurements, and determined the magnetic ground state by neutron powder diffraction study. An upturn is observed below 6 K in C_p(T)/T, however both C_p(T) and \chi(T) do not show any clear anomaly down to 2 K. The \chi_ac(T) shows a well pronounced anomaly indicating an antiferromagnetic transition at T_N = 0.55 K. The long range antiferromagnetic ordering is confirmed by neutron diffraction. The refinement of neutron diffraction pattern reveals an all-in/all-out antiferromagnetic structure, where for successive tetrahedra, the four Nd3+ magnetic moments point alternatively all-into or all-out-of the tetrahedron, with an ordering wavevector k = (0, 0, 0) and an ordered state magnetic moment of m = 0.62(1) \mu_B/Nd at 0.1 K. The ordered moment is strongly reduced reflecting strong quantum fluctuations in ordered state.Comment: 10 pages, 9 figures and 2 tables; to appear in Phys. Rev.

120{\deg} Helical Magnetic Order in the Distorted Triangular Antiferromagnet alpha-CaCr2O4

{\alpha}-CaCr2O4 is a distorted triangular antiferromagnet. The magnetic Cr3+ ions which have spin-3/2 and interact with their nearest neighbors via Heisenberg direct exchange interactions, develop long-range magnetic order below T_N=42.6 K. Powder and single-crystal neutron diffraction reveal a helical magnetic structure with ordering wavevector k=(0,~1/3,0) and angles close to 120{\deg} between neighboring spins. Spherical neutron polarimetry unambiguously proves that the spins lie in the ac plane perpendicular to k. The magnetic structure is therefore that expected for an ideal triangular antiferromagnet where all nearest neighbor interactions are equal, in spite of the fact that {\alpha}-CaCr2O4 is distorted with two inequivalent Cr3+ ions and four different nearest neighbor interactions. By simulating the magnetic order as a function of these four interactions it is found that the special pattern of interactions in {\alpha}-CaCr2O4 stabilizes 120{\deg} helical order for a large range of exchange interactions.Comment: 13 pages, 12 figure

Metabolic profiling of HepG2 cells incubated with S(−) and R(+) enantiomers of anti-coagulating drug warfarin

Warfarin is a commonly prescribed oral anticoagulant with narrow therapeutic index. It achieves anti-coagulating effects by interfering with the vitamin K cycle. Warfarin has two enantiomers, S(−) and R(+) and undergoes stereoselective metabolism, with the S(−) enantiomer being more effective. We reported the intracellular metabolic profile in HepG2 cells incubated with S(−) and R(+) warfarin by GCMS. Chemometric method PCA was applied to analyze the individual samples. A total of 80 metabolites which belong to different categories were identified. Two batches of experiments (with and without the presence of vitamin K) were designed. In samples incubated with S(−) and R(+) warfarin, glucuronic acid showed significantly decreased in cells incubated with R(+) warfarin but not in those incubated with S(−) warfarin. It may partially explain the lower bio-activity of R(+) warfarin. And arachidonic acid showed increased in cells incubated with S(−) warfarin but not in those incubated with R(+) warfarin. In addition, a number of small molecules involved in γ-glutamyl cycle displayed ratio variations. Intracellular glutathione detection further validated the results. Taken together, our findings provided molecular evidence on a comprehensive metabolic profile on warfarin-cell interaction which may shed new lights on future improvement of warfarin therapy

Defining the critical hurdles in cancer immunotherapy

Scientific discoveries that provide strong evidence of antitumor effects in preclinical models often encounter significant delays before being tested in patients with cancer. While some of these delays have a scientific basis, others do not. We need to do better. Innovative strategies need to move into early stage clinical trials as quickly as it is safe, and if successful, these therapies should efficiently obtain regulatory approval and widespread clinical application. In late 2009 and 2010 the Society for Immunotherapy of Cancer (SITC), convened an "Immunotherapy Summit" with representatives from immunotherapy organizations representing Europe, Japan, China and North America to discuss collaborations to improve development and delivery of cancer immunotherapy. One of the concepts raised by SITC and defined as critical by all parties was the need to identify hurdles that impede effective translation of cancer immunotherapy. With consensus on these hurdles, international working groups could be developed to make recommendations vetted by the participating organizations. These recommendations could then be considered by regulatory bodies, governmental and private funding agencies, pharmaceutical companies and academic institutions to facilitate changes necessary to accelerate clinical translation of novel immune-based cancer therapies. The critical hurdles identified by representatives of the collaborating organizations, now organized as the World Immunotherapy Council, are presented and discussed in this report. Some of the identified hurdles impede all investigators; others hinder investigators only in certain regions or institutions or are more relevant to specific types of immunotherapy or first-in-humans studies. Each of these hurdles can significantly delay clinical translation of promising advances in immunotherapy yet if overcome, have the potential to improve outcomes of patients with cancer

SARS-CoV-2 Omicron-B.1.1.529 leads to widespread escape from neutralizing antibody responses

On 24th November 2021, the sequence of a new SARS-CoV-2 viral isolate Omicron-B.1.1.529 was announced, containing far more mutations in Spike (S) than previously reported variants. Neutralization titers of Omicron by sera from vaccinees and convalescent subjects infected with early pandemic Alpha, Beta, Gamma, or Delta are substantially reduced, or the sera failed to neutralize. Titers against Omicron are boosted by third vaccine doses and are high in both vaccinated individuals and those infected by Delta. Mutations in Omicron knock out or substantially reduce neutralization by most of the large panel of potent monoclonal antibodies and antibodies under commercial development. Omicron S has structural changes from earlier viruses and uses mutations that confer tight binding to ACE2 to unleash evolution driven by immune escape. This leads to a large number of mutations in the ACE2 binding site and rebalances receptor affinity to that of earlier pandemic viruses

ALG Calculus II (Lecture Slides)

Authors\u27 Description: Upon completing this course students should be able to: Find derivatives and integrals of transcendental functions. Apply techniques to evaluate integrals. Use tests to determine series convergence. Determine Taylor series for common functions. Describe curves in parametric form and polar coordinates. Important Note: All are welcome to use and modify these slides for nonprofit educational activities. They are intended to be used with smart board/smart podium or touch screen technology and cannot serve as a primary text. They were produced with LaTeX and converted to .ppt. The original Beamer slides are superior quality but require several additional figure files. Anyone interested in the source files or wishing to report errata please contact Lake Ritter at [email protected]

Proposal and Report for Grant 007: Calculus II

This proposal and final report are from the first ALG grants finishing between Spring 2015 and Spring 2016. They have been republished in the repository in order to move our first reports over from being hosted on the ALG website

ALG Calculus II Portal (Open Course)

Authors\u27 Description: Upon completing this course students should be able to: Find derivatives and integrals of transcendental functions. Apply techniques to evaluate integrals. Use tests to determine series convergence. Determine Taylor series for common functions. Describe curves in parametric form and polar coordinates

An Incentivized Early Remediation Program in Calculus I

Strong prerequisite skills are essential to student success in the calculus sequence; however, many students arrive in Calculus I with weaknesses that are difficult for them to overcome. In this paper, we describe an approach to early incentivized remediation of prerequisite material in a Calculus I course. We present data that supports the idea that a lack of prerequisite knowledge is a significant hurdle for students, but also that participation in the remediation program is correlated with student success. In addition, the program allows for the very early identification of students at high risk of failing. The program is easy to implement, and it would be adaptable to a variety of other courses for which prerequisite knowledge is essential for success including science courses, engineering courses and other mathematics courses

Using Strand Committees to Build Faculty Support for Departmental Change

In this article, the authors propose a department-level curricular committee structure, called Strand Committees, as a mechanism to facilitate oversight and enact significant change to policies and practices in specific courses. The primary goal of the Strand Committees is improving both student success and instruction while upholding a high degree of shared governance. The focus of this paper is based around three recommendations encapsulating the philosophy of Strand Committees: increasing faculty buy-in for change efforts; capitalizing on the enthusiasm of a few faculty members to serve as change agents; and structuring the committees so participation is open, voluntary, and there is continuity to the work. The authors present the history and context of Strand Committees at a large, recently consolidated public university, highlight examples of successful and beneficial changes resulting from this work, and discuss how Strand Committees may lead to supporting improvements in teaching and learning in undergraduate mathematics