Plug-and-Play Medical Dialogue System

Medical dialogue systems aim to provide accurate answers to patients, necessitating specific domain knowledge. Recent advancements in Large Language Models (LLMs) have demonstrated their exceptional capabilities in the medical Q&A domain, indicating a rich understanding of common sense. However, LLMs are insufficient for direct diagnosis due to the absence of diagnostic strategies. The conventional approach to address this challenge involves expensive fine-tuning of LLMs. Alternatively, a more appealing solution is the development of a plugin that empowers LLMs to perform medical conversation tasks. Drawing inspiration from in-context learning, we propose PlugMed, a Plug-and-Play Medical Dialogue System that facilitates appropriate dialogue actions by LLMs through two modules: the prompt generation (PG) module and the response ranking (RR) module. The PG module is designed to capture dialogue information from both global and local perspectives. It selects suitable prompts by assessing their similarity to the entire dialogue history and recent utterances grouped by patient symptoms, respectively. Additionally, the RR module incorporates fine-tuned SLMs as response filters and selects appropriate responses generated by LLMs. Moreover, we devise a novel evaluation method based on intent and medical entities matching to assess the efficacy of dialogue strategies in medical conversations more effectively. Experimental evaluations conducted on three unlabeled medical dialogue datasets, including both automatic and manual assessments, demonstrate that our model surpasses the strong fine-tuning baselines.Comment: 9 pages, 3 figures, Possible submission to Emnlp or AAA

Nano-Hertz gravitational waves from collapsing domain walls associated with freeze-in dark matter in light of pulsar timing array observations

Evidence for a stochastic gravitational wave background in the nHz frequency band is recently reported by four pulsar timing array collaborations NANOGrav, EPTA, CPTA, and PPTA. It can be interpreted by gravitational waves from collapsing domain walls in the early universe. We assume such domain walls arising from the spontaneous breaking of a $Z_2$ symmetry in a scalar field theory, where a tiny $Z_2$-violating potential is required to make domain walls unstable. We propose that this $Z_2$-violating potential is radiatively induced by a feeble Yukawa coupling between the scalar field and a fermion field, which is also responsible for dark matter production via the freeze-in mechanism. Combining the pulsar timing array data and the observed dark matter relic density, we find that the model parameters can be narrowed down to small ranges.Comment: 18 pages, 6 figure

Fabrication of porous Al2O3-based ceramics using combustion synthesized powders

Porous Al2O3-based ceramics were fabricated from powders synthesized via a solution combustion process using starch and urea as fuels. Effects of the relative fuel-to-oxidant ratio (φe = 1.4, 1.6, 1.8 and 2.0, respectively) on open porosity, pore size distribution and flexural strength of the as-prepared porous Al2O3-based ceramics were investigated. Experimental results revealed that the densification ability of the as-synthesized powders increased significantly as φe increased, and open porosity, pore size distribution and flexural strength of the porous ceramics exhibited remarkable dependence on the densification ability of the powders instead of the weight fraction of the charred organic residuals in the powders. SEM micrographs disclosed that the porous ceramics from the precursors with φe = 1.8 or 2.0 exhibited significantly homogenous microstructures including pore size and pore distribution

Diversity of archaea and bacteria in a biogas reactor fed with Pennisetum sinese Roxb by 16S rRNA sequence analysis

Purpose: To investigate the structure and function of the complex rumen microbial community in a biogas reactor by 16S rRNA gene analysis, which was fed with Pennisetum sinese Roxb as the monosubstrate.Methods: Two 16S ribosomal RNA (rRNA) clone libraries of bacteria and archaea were established by polymerase chain reaction. Community structure was determined by phylogenetic analyses of 119 and 100 16S rRNA gene clones from the bacterial and archaeal libraries, respectively.Results: In the bacterial library, 13.4 % of clones were affiliated with Treponema porcinum, 5.9 % with Eubacterium limosum, 5 % with Clostridium, 5 % with Bacteroidetes, 4.2 % with Firmicutes, 2.5 % with Anaerofilum and a total of 64 % clones belonged to unclassified or uncultured bacteria. In the archaeal library, Methanobacterium curvum made up 12 % of known clones, Methanosarcina barkeri represented 8 %, Methanobacterium bryantii represented 4 % and Methanofollis ethanolicus represented 2 %, respectively; the remaining 74 % of the clones were unclassified archaebacteria.Conclusion: T. porcinum and M. curvum are the most predominant bacteria and archaea in a biogas reactor fed with P. sinese as the sole substrate.Keywords: Pennisetum sinese Roxb, Archaea, Bacteria, Biogas reactor, 16S rDNA sequencin

Phase transition gravitational waves from pseudo-Nambu-Goldstone dark matter and two Higgs doublets

We investigate the potential stochastic gravitational waves from first-order electroweak phase transitions in a model with pseudo-Nambu-Goldstone dark matter and two Higgs doublets. The dark matter candidate can naturally evade direct detection bounds, and can achieve the observed relic abundance via the thermal mechanism. Three scalar fields in the model obtain vacuum expectation values, related to phase transitions at the early Universe. We search for the parameter points that can cause first-order phase transitions, taking into account the existed experimental constraints. The resulting gravitational wave spectra are further evaluated. Some parameter points are found to induce strong gravitational wave signals, which have the opportunity to be detected in future space-based interferometer experiments LISA, Taiji, and TianQin.Comment: 34 pages, 8 figure

Corrections to electroweak precision observables from mixings of an exotic vector boson in light of the CDF WW-mass anomaly

We enumerate various effective couplings that contribute to the mixings between an exotic vector boson $Z^{\prime}$ and the neutral electroweak vector bosons. The miscellaneous mixing patterns can be evaluated perturbatively. The effective oblique parameters $S^{\prime}$, $T^{\prime}$, and $U^{\prime}$ are calculated to compare with the electroweak precision test results. With the contributions to the non-negligible $U^{\prime}$ parameter from the $\epsilon_{B,W}$ parameters and the aid of some other parameters to cancel the negative $T^{\prime}$, the recent CDF $W$-mass anomaly can therefore be explained.Comment: S, T, U parameters are changed to the effective S', T', U'. Further detailed discussions about the parameter definitions and the corresponding effective operators are elaborated in the appendix. Figures are update

Vector dark matter from split SU(2) gauge bosons

We propose a vector dark matter model with an exotic dark SU(2) gauge group. Two Higgs triplets are introduced to spontaneously break the symmetry. All of the dark gauge bosons become massive, and the lightest one is a viable vector DM candidate. Its stability is guaranteed by a remaining Z_2 symmetry. We study the parameter space constrained by the Higgs measurement data, the dark matter relic density, and direct and indirect detection experiments. We find numerous parameter points satisfying all the constraints, and they could be further tested in future experiments. Similar methodology can be used to construct vector dark matter models from an arbitrary SO(N) gauge group.Comment: 25 pages, 5 figure