ZYG-9ch-TOG promotes the stability of acentrosomal poles via regulation of spindle microtubules in C. elegans oocyte meiosis

During mitosis, centrosomes serve as microtubule organizing centers that guide the formation of a bipolar spindle. However, oocytes of many species lack centrosomes; how meiotic spindles establish and maintain these acentrosomal poles remains poorly understood. Here, we show that the microtubule polymerase ZYG-9ch-TOG is required to maintain acentrosomal pole integrity in C. elegans oocyte meiosis; following acute depletion of ZYG-9 from pre-formed spindles, the poles split apart and an unstable multipolar structure forms. Depletion of TAC-1, a protein known to interact with ZYG-9 in mitosis, caused loss of proper ZYG-9 localization and similar spindle phenotypes, further demonstrating that ZYG-9 is required for pole integrity. However, depletion of ZYG-9 surprisingly did not affect the assembly or stability of monopolar spindles, suggesting that ZYG-9 is not required for acentrosomal pole structure per se. Moreover, fluorescence recovery after photobleaching (FRAP) revealed that ZYG-9 turns over rapidly at acentrosomal poles, displaying similar turnover dynamics to tubulin itself, suggesting that ZYG-9 does not play a static structural role at poles. Together, these data support a global role for ZYG-9 in regulating the stability of bipolar spindles and demonstrate that the maintenance of acentrosomal poles requires factors beyond those acting to organize the pole structure itself.

Recursive structure of the Gauß hypergeometric function and boundary/crosscap conformal block

The Gauß hypergeometric function shows a recursive structure which resembles those found in conformal blocks. We compare it with the recursive structure of the conformal block in boundary/crosscap conformal field theories that is obtained from the representation theory. We find that the pole structure perfectly agrees but the recursive structure in the Gauß hypergeometric function is slightly “off-shell”.

Lightning Protection Improvement and Economic Evaluation of Thailand’s 24 kV Distribution Line Based on Difference in Grounding Distance of Overhead Ground Wire

This study determines the voltage across insulators after a direct lightning strike to an overhead ground wire on a 24 kV pole structure for different grounding distances of overhead ground wire, to calculate the maximum ground resistance required to avoid disruption of the distribution line system using ATP-EMTP software. The results show that when a 40 kA lightning current, the average lightning current in Thailand, strikes a 24 kV pole structure, the maximum ground resistance should not exceed 4 Ω for a 40 m grounding distance of overhead ground wire, based on an existing critical insulator flashover of 205 kV. However, because the average ground resistance in Thailand is approximately 10 Ω, this study proposes increasing the insulation level from 205 kV to 300 kV to reduce the likelihood of power outage. The cost-effectiveness of such an investment is assessed in terms of net present value (NPV), internal rate of return (IRR), profitability index (PI), and discounted payback period (DPP) using existing economic tools. Results show that when the critical insulator flashover is increased from 205 kV to 300 kV for a 40 m grounding distance of overhead ground wire, the project is likely to have a DPP of 15.12 years, NPV of 143,321.87 USD, IRR of 12%, and PI of 1.15. On the other hand, grounding distances greater than 40 m for overhead ground wire result in negative NPV, although the back flashover rate can be reduced by 1.51–5.71% with grounding distances of 80–200 m compared to the situation in the absence of grounding.

Is two-pole’s $$\varLambda (1405)$$ one state or two?

To understand the nature of two poles for the $$\varLambda (1405)$$ Λ ( 1405 ) state, we revisit the interactions of $${\bar{K}}N$$ K ¯ N and $$\pi \Sigma $$ π Σ with their coupled channels, where two-pole structure is found in the second Riemann sheet. We also dynamically generate two poles in the single channel interaction of $${\bar{K}}N$$ K ¯ N and $$\pi \Sigma $$ π Σ , respectively. Moreover, we make a further study of two poles’ properties by evaluating the couplings, the compositeness, the wave functions, and the radii for the interactions of four coupled channels, two coupled channels and the single channel. Our results show that the nature of two poles is unique. The higher-mass pole is a pure $${\bar{K}} N$$ K ¯ N molecule, and the lower-mass one is a composite state of mainly $$\pi \Sigma $$ π Σ with tiny component $${\bar{K}} N$$ K ¯ N . From our results, one can conclude that the $$\varLambda (1405)$$ Λ ( 1405 ) state may be overlapped with two different states of the same quantum numbers.

The $${\varvec{\Lambda (1405)}}$$ in resummed chiral effective field theory

We study the unitarized meson–baryon scattering amplitude at leading order in the strangeness $$S=-1$$ S = - 1 sector using time-ordered perturbation theory for a manifestly Lorentz-invariant formulation of chiral effective field theory. By solving the coupled-channel integral equations with the full off-shell dependence of the effective potential and applying subtractive renormalization, we analyze the renormalized scattering amplitudes and obtain the two-pole structure of the $$\Lambda (1405)$$ Λ ( 1405 ) resonance. We also point out the necessity of including higher-order terms.

Two-pole structures in a relativistic Friedrichs–Lee-QPC scheme

A general appearance of two-pole structures is exhibited in a relativistic Friedrichs–Lee model combined with a relativistic quark pair creation model in a consistent manner. This kind of two-pole structure could be found when a $$q\bar{q}$$ q q ¯ state couples to the open-flavor continuum state in the S partial wave. We found that many enigmatic states, such as $$f_0(500)/\sigma $$ f 0 ( 500 ) / σ , $$K_0^*(700)/\kappa $$ K 0 ∗ ( 700 ) / κ , $$a_0(980)$$ a 0 ( 980 ) , $$f_0(980)$$ f 0 ( 980 ) , $$D_0^*(2300)$$ D 0 ∗ ( 2300 ) , $$D_{s0}^*(2317)$$ D s 0 ∗ ( 2317 ) , and X(3872), together with another higher state for each, all result from this kind of two-pole structures. Furthermore, an interesting observation is that this kind of two-pole structure will contribute roughly a total of $$180^\circ $$ 180 ∘ phase shift for the scattering process in a single channel approximation. This relativistic scheme may provide more insights into the understanding of the properties of non-$$q\bar{q}$$ q q ¯ state. It is also suggested that such two-pole structure could be a common phenomenon which deserves studying both from theoretical and experimental perspectives.

Large $$N_\mathrm{f}$$ for multiple representations

We present an extension of the large-$$N_\mathrm{f}$$ N f formalism that allows one to study cases with multiple fermion representations. The pole structure in the beta function is traced back to the intrinsic non-abelian nature of the gauge group, independently from the fermion representation. This result validates the conjectured existence of an interactive UV fixed point for non-abelian gauge theories with large fermion multiplicity. Finally, we apply our results to chiral gauge theories.

JALUR KERETA API PELABUHAN CIREBON: JEJAK ANGKUTAN KOMODITAS PERDAGANGAN PADA MASA KOLONIAL BELANDA 1897-1942

The high demand for various plantation commodities in the world market, especially sugar, encourages the construction and operation of railroad lines in the Cirebon region. The construction and operation of railroad lines in Cirebon are directed to facilitate commodity traffic to be sent through the Port of Cirebon. The problem raised in this paper is related to what archeological remains are markers of the existence of the Cirebon-Cirebon Port Railway. The method used to answer these problems is the descriptive analysis method. Data collection was carried out through literature study and field observations. Dutch colonial railroad relics on the track in the form of the railbed, signal pole structure, boundary stakes, bridge structure, level crossing pole structure, and rail rods that are still installed. The existence of the railroad remains is a proof of the activities of the train transportation mode to the Port of Cirebon. Tingginya permintaan berbagai komoditas perkebunan di pasaran dunia, terutama gula mendorong dibangun dan dioperasikannya jalur kereta api di wilayah Cirebon. Pembangunan dan pengoperasian jalur kereta api di Cirebon diarahkan untuk memperlancar lalu lintas komoditas yang akan dikirim melalui Pelabuhan Cirebon. Salah satu bagian dari jalur kereta api yang dibangun, adalah jalur Stasiun cirebon - Pelabuhan Cirebon. Permasalahan yang diangkat pada tulisan ini, adalah berkenaan dengan tinggalan arkeologi apa saja yang menjadi penanda keberadaan Jalur kereta api Cirebon - Pelabuhan Cirebon. Metode yang dipergunakan untuk menjawab permasalahan tersebut, adalah Metode deskriptif analisis. Pengumpulan data dilakukan melalui studi Pustaka, dan pengamatan lapangan. Saat ini, Jalur kereta Cirebon - Pelabuhan merupakan jalur tidak aktif di wilayah Cirebon. Tinggalan perkeretaapian masa Kolonial belanda di jalur tersebut berupa railbed, struktur tiang sinyal, patok batas, patok KM, struktur jembatan, struktur tiang perlintasan sebidang, dan batang rel yang masih terpasang. Keberadaan tinggalan perkeretaapian tersebut merupakan bukti aktifitas moda angkutan kereta api menuju Pelabuhan Cirebon.