On topological cyclic homology

Topological cyclic homology is a refinement of Connes--Tsygan's cyclic homology which was introduced by B\"okstedt--Hsiang--Madsen in 1993 as an approximation to algebraic $K$-theory. There is a trace map from algebraic $K$-theory to topological cyclic homology, and a theorem of Dundas--Goodwillie--McCarthy asserts that this induces an equivalence of relative theories for nilpotent immersions, which gives a way for computing $K$-theory in various situations. The construction of topological cyclic homology is based on genuine equivariant homotopy theory, the use of explicit point-set models, and the elaborate notion of a cyclotomic spectrum. The goal of this paper is to revisit this theory using only homotopy-invariant notions. In particular, we give a new construction of topological cyclic homology. This is based on a new definition of the $\infty$-category of cyclotomic spectra: We define a cyclotomic spectrum to be a spectrum $X$ with $S^1$-action (in the most naive sense) together with $S^1$-equivariant maps $\varphi_p: X\to X^{tC_p}$ for all primes $p$. Here $X^{tC_p}=\mathrm{cofib}(\mathrm{Nm}: X_{hC_p}\to X^{hC_p})$ is the Tate construction. On bounded below spectra, we prove that this agrees with previous definitions. As a consequence, we obtain a new and simple formula for topological cyclic homology. In order to construct the maps $\varphi_p: X\to X^{tC_p}$ in the example of topological Hochschild homology we introduce and study Tate diagonals for spectra and Frobenius homomorphisms of commutative ring spectra. In particular we prove a version of the Segal conjecture for the Tate diagonals and relate these Frobenius homomorphisms to power operations

Measurement of calcium isotopes (δ44Ca) using a multicollector TIMS technique

We propose a new“multicollector technique” for the thermal ionization mass spectrometer (TIMS) measurement of calcium (Ca) isotope ratios improving average internal statistical uncertainty of the 44Ca/40Ca measurements by a factor of 2–4 and average sample throughput relative to the commonly used “peak jumping method” by a factor of 3. Isobaric interferences with potassium (40K+) and titanium (48Ti+) or positively charged molecules like 24Mg19F+, 25Mg19F+, 24Mg16O+ and 27Al16O+ can either be corrected or are negligible. Similar, peak shape defects introduced by the large dispersion of the whole Ca isotope mass range from 40–48 atomic mass units (amu) do not influence Ca-isotope ratios. We use a 43Ca/48Ca double spike with an iterative double spike correction algorithm for precise isotope measurement

Presentation of exogenous protein antigens by dendritic cells to T cell clones: intact protein is presented best by immature, epidermal Langerhans cells

Romani, N., Koide, S., Crowley, M., Witmer-Pack, M., Livingston, A.M., Fathman, C.G., Inaba, K., and Steinman, R.M. Presentation of exogenous protein antigens by dendritic cells to T cell clones: intact protein is presented best by immature, epidermal Langerhans cells. J. Exp. Med. 169: 1169-1178, 1989https://digitalcommons.rockefeller.edu/historical-scientific-reports/1023/thumbnail.jp

Beyond the Ice

Leadership is a management tool to direct effective achievement of goals. Historical investigation can provide a valuable lens for the study of leadership styles. To that end, this study examines the disparate approaches of Roald Amundsen and Robert Scott as they raced to be the first explorer to reach the South Pole. The objective of this study is to analyze the leadership techniques used in these expeditions, and to determine how they shaped the outcome of each. The process of tacit knowledge and experience coalesce and foster both leadership and action that is not only communication-oriented and value-driven, but also rooted in growth mindset and reflexivity. Both of these concepts proved to be imperative to the success of both Amundsen and Scott’s expeditions. Ultimately, the experiences, choices, and eventual fate of polar explorers Roald Amundsen and Robert Scott provide a unique view of the human endeavor that holds valuable lessons for leaders in a variety of professional settings

The nonrelativistic limit of the relativistic point coupling model

We relate the relativistic finite range mean-field model (RMF-FR) to the point-coupling variant and compare the nonlinear density dependence. From this, the effective Hamiltonian of the nonlinear point-coupling model in the nonrelativistic limit is derived. Different from the nonrelativistic models, the nonlinearity in the relativistic models automatically yields contributions in the form of a weak density dependence not only in the central potential but also in the spin-orbit potential. The central potential affects the bulk and surface properties while the spin-orbit potential is crucial for the shell structure of finite nuclei. A modification in the Skyrme-Hartree-Fock model with a density-dependent spin-orbit potential inspired by the point-coupling model is suggested.Comment: 21 pages, latex, 1 eps figure. accepted for publication in annals of physic

Effect of The Inclusion of Butterfly Pea (Clitoria ternatea) and Green Sea Weed (Ulva lactuca) in The Complete Feed on The Concentration of Blood Metabolites of Male Kacang Goats

This experiment aimed to investigate the effect of including  Clitoria ternatea and Ulva lactuca in the complete feed on the concentration of blood metabolites of male kacang goats. Four male kacang goats were involved in this experiment arranged following a Latin Square Design with 4 treatments and 4 periods as replication. The treatments were R0= native grass hay 60%+concentrate 40%, R1= native grass hay 30%+concentrate 40%+ Clitoria ternatea 30%, R2= native grass hay 30%+concentrate 40%+ Clitoria ternatea 15%+ Ulva lactuca 15% and R3= native grass hay 30%+ concentrate 40%+Ulva lactuca 30%. Data were analyzed using analysis of variance (ANOVA) and followed by the Duncan Multiple Range Test when significant differences were found. The results showed that  feeding a complete feed containing  Clitoria ternatea and Ulva lactuca did not significantly (P>0,05) affect the concentration of urea, glucose and  plasm total protein in the blood of male kacang goats. Therefore, it can be concluded the inclusion of Clitoria ternatea and Ulva lactuca has no effect on the concentration of blood metabolites in male kacang goats

PENGARUH PEMBERIAN SILASE CAMPURAN RUMPUT DAN DAUN MARKISA HUTAN DENGAN PROPORSI YANG BERBEDA TERHADAP TINGKAH LAKU KAMBING KACANG (Effect of feeding silage made of different ratio of kume grass and wild markisa leaves on feeding beahavior of male kacan

This research aimed to study the effect of feeding silage of kume grass  and Pasiflora foetida leaves differing in their ratio on fiber intake and digestibility, rumen VFA and blood glucose concentration of male kacang goats. This study used four male kacang goats with the average body wight of 10,5 kg. This experiment followed a 4x4 Latin Square design with four treatments in four 21-day periods as replications. The treatments were M0 : silage made of 100 %  kume grass, M20 : silage made of 80% kume grass  + 20% Passiflora foetida, M40 : 60% kume grass + passiflora foetida 40%, M60 : 40% kume grass  + 60% Passiflora foetida.  Result showed that feeding silage made of different ratio of kume grass and Passiflora foetida leaves did not significantly (P>0,05) affect the length and frequency of eating, the length of rumination period as well as the length and frequency of resting period. Therefore, it can be concluded that inclusion of P. foetida in the silage mix with kume grass up to 60% is considered save as it did not affect the feeding behaviour of Kacang goats.Penelitian ini bertujuan untuk mengetahui pengaruh pemberian pakan lengkap silase berbasis rumput kume dan daun markisa hutan dengan rasio yang berbeda terhadap tingkah laku makan ternak kambing kacang. Penelitian ini menggunakan Rancangan Bujur Sangkar Latin (RBSL) dengan empat perlakuan pemberian campuran silase rumput kume dan daun markisa hutan serta empat periode pengambilan data sebagai ulangan. Keempat perlakuan tersebut adalah  M0 : 100 %  silase Rumput  Kume, M20 : Rumput Kume 80%  +  Markisa Hutan 20 %, M40 : Rumput Kume 60% + Markisa Hutan  40 %, M60 : Rumput Kume 40 % + Markisa Hutan 60 %. Parameter yang diukur terdiri dari frekuensi dan lama makan, frekuensi dan lama ruminasi serta frekuensi dan lama istirahat. Hasil penelitian menunjukan bahwa pemberian silase campuran rumput kume dan daun markisa hutandalam proporsi yang berbeda  tidak berpengaruh nyata ( P>0,05) terhadap lama dan frekuensi makan, lama ruminasi serta lama dan frekuensi istirahat kambing kacang. Disimpulkan bahwa pemberian silase campuran rumput kume dan  daun markisa hutan dengan proporsi yang berbeda tidak berpengaruh nyata terhadap tingkah laku makan kambing kacang

Students\u27 Emotions for Achievement and Technology Use in Synchronous Hybrid Graduate Programmes: A Control-Value Approach

Synchronous hybrid delivery (simultaneously teaching on-campus and online students using web conferencing) is becoming more common; however, little is known about how students experience emotions in this learning environment. Based on Pekrun’s (2006) control-value theory of emotions, the dual purpose of this study was first to compare synchronous hybrid students who attend online versus on-campus in terms of control, value, emotions and perceived success and second to compare students’ degree of emotional activation in the domains of programme achievement and technology use. Survey data from 101 graduate business students revealed that online students reported significantly higher levels of technology-related anger, anxiety and helplessness. Furthermore, in compar- ison to their on-campus counterparts, online students more clearly separated their emotions in terms of programme achievement and technology use. Emotions related significantly to students’ perceived success for both programme achieve- ment and technology use, and mediated the effects of control and value appraisals on perceived success