Warped Brane worlds in Critical Gravity

We investigate the brane models in arbitrary dimensional critical gravity presented in [Phys. Rev. Lett. 106, 181302 (2011)]. For the model of the thin branes with codimension one, the Gibbons-Hawking surface term and the junction conditions are derived, with which the analytical solutions for the flat, AdS, and dS branes are obtained at the critical point of the critical gravity. It is found that all these branes are embedded in an AdS$_{n}$ spacetime, but, in general, the effective cosmological constant $\Lambda$ of the AdS$_{n}$ spacetime is not equal to the naked one $\Lambda_0$ in the critical gravity, which can be positive, zero, and negative. Another interesting result is that the brane tension can also be positive, zero, or negative, depending on the symmetry of the thin brane and the values of the parameters of the theory, which is very different from the case in general relativity. It is shown that the mass hierarchy problem can be solved in the braneworld model in the higher-derivative critical gravity. We also study the thick brane model and find analytical and numerical solutions of the flat, AdS, and dS branes. It is find that some branes will have inner structure when some parameters of the theory are larger than their critical values, which may result in resonant KK modes for some bulk matter fields. The flat branes with positive energy density and AdS branes with negative energy density are embedded in an $n$-dimensional AdS spacetime, while the dS branes with positive energy density are embedded in an $n$-dimensional Minkowski one.Comment: 14 pages, 7 figures, updated version, accepted by EPJ

Study on transient voltage distribution characteristics of transformer windings

Very fast transient overvoltage (VFTO) with large waveform steepness and high amplitude can cause great harm to winding insulation of transformers and other equipment connected to it. Therefore, a transformer winding model is designed and described in this paper. Transient overvoltage test is carried out by pinning method and non-contact measuring sensor respectively. Then the simulation results are compared with those of VFTO distribution calculation program for transformer equipment. The results show that the simulation results are close to the actual test results. Finally, combining with the experimental measurement and simulation data, the potential distribution in transformer windings under the effect of fast transient overvoltage is analysed to guide the overvoltage protection of transformer winding insulation

Effects of immersing treatment of curcumin and piperine combined with vacuum packaging on the quality of salmon (Salmo salar) during cold chain logistics

In order to study the effects of the compound preservatives (curcumin and piperine (CP)) and vacuum packaging (VP) on the quality of salmon during cold chain logistics suffered from temperature abuse, the physiochemical indexes (texture, water holding capacity (WHC), total volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARS), free amino acids (FAA) contents), microbial indicators (total mesophilic bacteria count (MBC), total psychrotrophic bacteria count (PBC), H2S-producing bacteria count (HSBC)) were determined, and the moisture changes were explored by near-infrared (NIR) spectroscopy and low-field nuclear magnetic resonance (LF-NMR). The results showed that the treatment of curcumin and piperine in combination with vacuum packaging could maintain the quality of salmon suffered from temperature abuse most effectively. At the end of storage, the MBC of VP+CP was only 4.95 log CFU/g, which was about 1 log CFU/g lower than the control sample stored at the same condition. The combined treatment also retarded the increase of TVB-N, TBARS, and the decrease of hardness, springiness, and a* value, as well as water migration in salmon, contributing to higher water holding capacity and better appearance. Besides, VP+CP retarded the decrease of free glutamate, which contributed to umami taste. Due to the biological activity and safety of the preserves, the combined treatment could be a promising method for preservation of seafood.Peer reviewe

Cluster Language Model for Improved E-Commerce Retrieval and Ranking: Leveraging Query Similarity and Fine-Tuning for Personalized Results

This paper proposes a novel method to improve the accuracy of product search in e-commerce by utilizing a cluster language model. The method aims to address the limitations of the bi-encoder architecture while maintaining a minimal additional training burden. The approach involves labeling top products for each query, generating semantically similar query clusters using the K-Means clustering algorithm, and fine-tuning a global language model into cluster language models on individual clusters. The parameters of each cluster language model are fine-tuned to learn local manifolds in the feature space efficiently, capturing the nuances of various query types within each cluster. The inference is performed by assigning a new query to its respective cluster and utilizing the corresponding cluster language model for retrieval. The proposed method results in more accurate and personalized retrieval results, offering a superior alternative to the popular bi-encoder based retrieval models in semantic search.Comment: Accepted at The 6th Workshop on e-Commerce and NLP (ECNLP 6), KDD'23, Long Beach, C

Serum sex hormone binding globulin profile and its association with insulin resistance in Chinese peri-menopausal women

Wstęp: Celem badania było oznaczenie profilu stężeń globuliny wiążącej hormony płciowe (SHBG) w surowicy u Chinek będących w okresie okołomenopauzalnym oraz ocena korelacji tego profilu z parametrem insulinooporności HOMA-IR w tej szczególnej populacji. Materiał i metody: Przeprowadzono badanie przekrojowe metodą doboru grupowego z udziałem 1827 kobiet przebywających w szpitalu na rutynowych badaniach kontrolnych. Oznaczono profil stężeń SHBG i parametry statusu hormonalnego, parametry otyłości i parametry metaboliczne. Uczestniczki badania podzielono ze względu na wiek i status menstruacyjny na trzy grupy: grupę w okresie przedmenopauzalnym, grupę w okresie okołomenopauzalnym i grupę w okresie pomenopauzalnym. Wyniki: Stwierdzono, że stężenie SHBG w surowicy wykazuje ujemną korelację z BMI we wszystkich grupach i wzrasta z wiekiem kobiet w wieku reprodukcyjnym. Stężenie SHBG ulegało też, niezależnie od wieku, znamiennemu wzrostowi od początku zmian menopauzalnych, a następnie, po menopauzie, ulegało nieznacznemu zmniejszeniu. Po wzięciu poprawek na wiek i BMI, stwierdzono, że HOMA-IR u kobiet w okresie okołomenopauzalnym wykazuje ścisły związek wyłącznie z SHBG. Stwierdzono, że stężenie SHBG jest jedynym niezależnym istotnym determinantem HOMA-IR. Na podstawie analizy krzywej ROC dla predykcji insulinooporności na podstawie wartości HOMA-IR stwierdzono, że AUC dla SHBG osiąga wartość 0,816 (95% przedział ufności: 0,636–0,996). W przypadku kobiet w okresie okołomenopauzalnym najlepszą wartość odcięcia odróżniającą kobiety z insulinoopornością od kobiet bez insulinooporności jest 41,73 nmol/l przy czułości wynoszącej 81,4% i swoistości wynoszącej 87,5%. Wnioski: U Chinek w okresie okołomenopauzalnym niskie stężenie SHBG może stanowić niezależny czynnik ryzyka insulinooporności. (Endokrynol Pol 2013; 64 (3): 197–202)Introduction: The aim of this study was to measure serum sex hormone binding globulin (SHBG) profile in Chinese peri-menopausal women, and assess its correlation with insulin resistance (IR)-related parameter, namely HOMA-IR, in this special population. Material and methods: A cross-sectional study by the method of cluster sampling was performed in 1,827 women, who were in hospital for routine check-up. Serum SHBG profile and anthropometric indices of hormonal, adiposity, and metabolic variables were measured. According to their age and menstruation status, the subjects were divided into three groups: pre-menopause group, peri-menopause group, and post-menopause group. Results: Serum SHBG level was found to be negatively correlated with BMI in all groups and to increase in parallel with age in women of reproductive age. However, independently of age, it significantly increased from the onset of menopause transition, and slightly declined after menopause. After adjustment for age and BMI, HOMA-IR in peri-menopausal women was closely related only to SHBG. SHBG level was found to be the only independent significant determinant of HOMA-IR. On the basis of ROC curve analysis for the prediction of insulin resistance using HOMA-IR value, AUC for SHBG reached a value of 0.816 (0.636–0.996, 95% confidence interval). The best cutoff value that discriminates peri-menopausal women with or without insulin resistance is 41.73 nmol/L, with a sensitivity of 81.4% and a specificity of 87.5%. Conclusions: Low SHBG level may be an independent risk factor of insulin resistance in Chinese peri-menopausal women. (Endokrynol Pol 2013; 64 (3): 197–202