Origin of the near-room temperature resistance transition in lutetium with H2/N2 gas mixture under high pressure.

The recent report of room-temperature superconductivity at near-ambient pressure in nitrogen-doped lutetium hydride (Lu-H-N) by Dasenbrock-Gammon et al. [Nature 615, 244-250 (2023)] has attracted tremendous attention due to its anticipated great impact on technology. However, the results could not be independently reproduced by other groups worldwide in follow-up studies, which elicited intense controversy. Here, we develop a reliable experimental protocol to minimize the extensively concerned extrinsic influences on the sample by starting the reaction from pure lutetium loaded with an H2/N2 gas mixture in a diamond anvil cell under different pressures and temperatures and simultaneously monitoring the entire chemical reaction process using in situ four-probe resistance measurements. Therefore, we could repeatedly reproduce the near-room temperature upsurge of electrical resistance at a relatively early stage of the chemical reaction. However, the mechanism is suggested to be a metal-to-semiconductor/insulator transition associated with the structural modulation in the non-stoichiometric Lu-H-N, rather than superconductivity.

On the multipath interference mitigation for high-speed IM-DD transmissions with Nyquist subcarrier modulation.

The performance of high-speed intensity modulation direct detection (IM-DD) transmissions is severely degraded due to the occurrence of multipath interference (MPI), especially when a higher-order modulation format is utilized. Here, we propose and demonstrate, for the first time to the best of our knowledge, that a Nyquist subcarrier modulation (Nyquist-SCM) format inherently exhibits resistance to the MPI. We experimentally evaluate the MPI tolerance by transmitting 56 Gbit/s PAM-4 signals and Nyquist-SCM 16QAM signals over the 2 km standard single-mode fiber (SSMF) when the C-band semiconductor laser with a linewidth of 1.7 MHz is utilized. In comparison with the PAM-4 format, the Nyquist-SCM 16QAM format can lead to an enhanced MPI tolerance of 4 dB at the KP4-FEC threshold of BER = 2 × 10-4. In addition, even with the help of MPI mitigation for the PAM-4 signals based on two newly reported methods, the utilization of Nyquist-SCM 16QAM signal can still guarantee an improved MPI tolerance of 1 dB.

Neoadjuvant sintilimab plus chemotherapy in EGFR-mutant NSCLC: Phase 2 trial interim results (NEOTIDE/CTONG2104).

The clinical efficacy of neoadjuvant immunotherapy plus chemotherapy remains elusive in localized epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC). Here, we report interim results of a Simon's two-stage design, phase 2 trial using neoadjuvant sintilimab with carboplatin and nab-paclitaxel in resectable EGFR-mutant NSCLC. All 18 patients undergo radical surgery, with one patient experiencing surgery delay. Fourteen patients exhibit confirmed radiological response, with 44% achieving major pathological response (MPR) and no pathological complete response (pCR). Similar genomic alterations are observed before and after treatment without influencing the efficacy of subsequent EGFR-tyrosine kinase inhibitors (TKIs) in vitro. Infiltration and T cell receptor (TCR) clonal expansion of CCR8+ regulatory T (Treg)hi/CXCL13+ exhausted T (Tex)lo cells define a subtype of EGFR-mutant NSCLC highly resistant to immunotherapy, with the phenotype potentially serving as a promising signature to predict immunotherapy efficacy. Informed circulating tumor DNA (ctDNA) detection in EGFR-mutant NSCLC could help identify patients nonresponsive to neoadjuvant immunochemotherapy. These findings provide supportive data for the utilization of neoadjuvant immunochemotherapy and insight into immune resistance in EGFR-mutant NSCLC.

Central Roles of ZmNAC128 and ZmNAC130 in Nutrient Uptake and Storage during Maize Grain Filling.

Grain filling is critical for determining yield and quality, raising the question of whether central coordinators exist to facilitate the uptake and storage of various substances from maternal to filial tissues. The duplicate NAC transcription factors ZmNAC128 and ZmNAC130 could potentially serve as central coordinators. By analyzing differentially expressed genes from zmnac128 zmnac130 mutants across different genetic backgrounds and growing years, we identified 243 highly and differentially expressed genes (hdEGs) as the core target genes. These 243 hdEGs were associated with storage metabolism and transporters. ZmNAC128 and ZmNAC130 play vital roles in storage metabolism, and this study revealed two additional starch metabolism-related genes, sugary enhancer1 and hexokinase1, as their direct targets. A key finding of this study was the inclusion of 17 transporter genes within the 243 hdEGs, with significant alterations in the levels of more than 10 elements/substances in mutant kernels. Among them, six out of the nine upregulated transporter genes were linked to the transport of heavy metals and metalloids (HMMs), which was consistent with the enrichment of cadmium, lead, and arsenic observed in mutant kernels. Interestingly, the levels of Mg and Zn, minerals important to biofortification efforts, were reduced in mutant kernels. In addition to their direct involvement in sugar transport, ZmNAC128 and ZmNAC130 also activate the expression of the endosperm-preferential nitrogen and phosphate transporters ZmNPF1.1 and ZmPHO1;2. This coordinated regulation limits the intake of HMMs, enhances biofortification, and facilitates the uptake and storage of essential nutrients.

Replacing soybean meal with fermented rapeseed meal in diets: potential effects on growth performance, antioxidant capacity, and liver and intestinal health of juvenile tilapia (Oreochromis niloticus).

This study aims to evaluate the effects of substituting soybean meal with fermented rapeseed meal (FRM) on growth, antioxidant capacity, and liver and intestinal health of the genetically improved farmed tilapia (GIFT, Oreochromis niloticus). A total of 450 tilapia (7.22 ± 0.15 g) were fed with five experimental diets, including a basal diet containing 40% soybean meal (CP0), which was subsequently replaced by 25% (CP25), 50% (CP50), 75% (CP75), and 100% (CP100) FRM in a recirculated aquiculture system for 9 weeks (30 fish per tank in triplicates). The results showed that the weight gain, specific growth rate, feed intake, feed efficiency, hepatosomatic index, and viscerosomatic index of fish in both CP75 and CP100 groups were significantly lower than those in CP0 group (P < 0.05). The fish in CP100 group had the lower content of muscle crude protein while the higher level of muscle crude lipid (P < 0.05). Activities of serum aspartate aminotransferase, alanine aminotransferase along with total triglyceride in CP100 group were significantly higher than those in CP0 group (P < 0.05). There were no significant differences in the contents of liver protease, amylase, and lipase among five groups (P > 0.05). The activities of liver total antioxidant capacity and superoxide dismutase exhibited the increased tendency with the increase of FRM replacement levels from 25 to 50% (P < 0.05), while then significantly decreased from 75 to 100% (P < 0.05). Histological morphology indicated that the fish in between CP75 and CP100 groups had poor liver and intestine health. Intestinal microbial diversity analysis showed that the relative abundance of Cetobacterium and Alcaligenaceae in both CP75 and CP100 groups were lower than that in other three groups. In conclusion, the maximum replacement level of soybean meal with FRM in the diet was determined to be 50% without compromising the growth performance, antioxidant status, and liver and intestinal health of tilapia under the current experimental conditions. The observed decrease in food intake and subsequent retarded growth performance in the CP75 and CP100 groups can be attributed directly to a reduction in feed palatability caused by FRM.

Tagpyrrollins A and B and Tagpyrrollidone A: Three Pyrrole Steroid Analogues with AKR1B1-Targeting Inhibitory Activity from the Sponges Stylissa massa and Pseudospongosorites suberitoides.

Pyrrole alkaloids (PAs) are a diverse class of natural products with complex carbon frameworks and broad bioactivities that are usually derived from marine sponges. Stylissa massa and Pseudospongosorites suberitoides are two independent sponges collected from the South China Sea in 2013 and 2018, respectively. We discovered PAs are common constituents in both two sponges; more specifically, S. massa produces pyrrole-imidazole alkaloids, and P. suberitoides contains pyrrolidone alkaloids. In this study, three pyrrole steroid metabolites were obtained. Compounds 1 and 2 are a pair of epimers sharing a new 5/7/5/6/6 pentacyclic structural configuration, and compound 3 has a new rigid 5/6/6 tricyclic structure. Interestingly, their scaffolds all possess a 6/6 bicyclic system on the featured classic pyrrole/pyrrolidone skeletons, so-dubbed tagpyrrollins A and B (1 and 2, respectively) and tagpyrrollidone A (3). From a biosynthetic viewpoint, 4,5-dihydroxypent-2-enal probably plays a crucial role in constructing these pyrrole steroid analogues. Based on our previous study on the inhibitory activity of spongiacidin targeting AKR1B1, a drug target for the treatment of chronic diabetic complications, in this study we found that tagpyrrolin A (1) also exhibits an inhibitory effect against AKR1B1.

Evaluation of Molecular Residual Disease by a Fixed Panel in Resectable Colorectal Cancer.

Purpose: Molecular residual disease (MRD) is a promising biomarker in colorectal cancer (CRC) for prognosis and guiding treatment, while the whole-exome sequencing (WES) based tumor-informed assay is standard for evaluating MRD based on circulating tumor DNA (ctDNA). In this study, we assessed the feasibility of a fixed-panel for evaluating MRD in CRC. Materials and Methods: 75 patients with resectable stage I-III CRC were enrolled. Tumor tissues obtained by surgery, and pre-operative and post-operative day 7 blood samples were collected. The ctDNA was evaluated using the tumor-agnostic and tumor-informed fixed assays, as well as the WES-based and panel-based personalized assays in randomly selected patients. Results: The tumor-informed fixed assay had a higher pre-operative positive rate than the tumor-agnostic assay (73.3% vs 57.3%). The pre-op ctDNA status failed to predict disease-free survival (DFS) in either of the fixed assays, while the tumor-informed fixed assay-determined post-op ctDNA positivity was significantly associated with worse DFS (HR, 20.74, 95%CI 7.19-59.83; p<0.001), which was an independent predictor by multivariable analysis (HR, 28.57, 95%CI 7.10-114.9; p<0.001). Sub-cohort analysis indicated the WES-based personalized assay had the highest pre-operative positive rate (95.1%). The two personalized assays and the tumor-informed fixed assay demonstrated same results in post-op landmark (HR, 26.34, 95%CI, 6.01-115.57; p<0.001), outperforming the tumor-agnostic fixed panel (HR, 3.04, 95%CI, 0.94-9.89; p=0.052). Conclusion: Our study confirmed the prognostic value of the ctDNA positivity at post-op day 7 by the tumor-informed fixed panel. The tumor-informed fixed panel may be a cost-effective method to evaluate MRD, which warrants further studies in future.

GPS-SUMO 2.0: an updated online service for the prediction of SUMOylation sites and SUMO-interacting motifs.

Small ubiquitin-like modifiers (SUMOs) are tiny but important protein regulators involved in orchestrating a broad spectrum of biological processes, either by covalently modifying protein substrates or by noncovalently interacting with other proteins. Here, we report an updated server, GPS-SUMO 2.0, for the prediction of SUMOylation sites and SUMO-interacting motifs (SIMs). For predictor training, we adopted three machine learning algorithms, penalized logistic regression (PLR), a deep neural network (DNN), and a transformer, and used 52 404 nonredundant SUMOylation sites in 8262 proteins and 163 SIMs in 102 proteins. To further increase the accuracy of predicting SUMOylation sites, a pretraining model was first constructed using 145 545 protein lysine modification sites, followed by transfer learning to fine-tune the model. GPS-SUMO 2.0 exhibited greater accuracy in predicting SUMOylation sites than did other existing tools. For users, one or multiple protein sequences or identifiers can be input, and the prediction results are shown in a tabular list. In addition to the basic statistics, we integrated knowledge from 35 public resources to annotate SUMOylation sites or SIMs. The GPS-SUMO 2.0 server is freely available at https://sumo.biocuckoo.cn/. We believe that GPS-SUMO 2.0 can serve as a useful tool for further analysis of SUMOylation and SUMO interactions.

Dietary cholesterol intervention could alleviate the intestinal injury of Oreochromis niloticus induced by plant-based diet via the intestinal barriers.

This study aims to explore the effects of supplementing cholesterol in plant-based feed on intestinal barriers (including physical barrier, chemical barrier, immune barrier, biological barrier) of GIFT strain tilapia (Oreochromis niloticus). Four isonitrogenous and isolipidic diets were prepared as follows: plant-based protein diet (Con group) containing corn protein powder, soybean meal, cottonseed meal, and rapeseed meal, with the addition of cholesterol at a level of 0.6 % (C0.6 % group), 1.2 % (C1.2 % group), and 1.8 % (C1.8 % group), respectively. A total of 360 fish (mean initial weight of (6.08 ± 0.12) g) were divided into 12 tanks with 30 fish per tank, each treatment was set with three tanks and the feeding period lasted 9 weeks. Histological analysis revealed that both the C0.6 % and C1.2 % groups exhibited a more organized intestinal structure, with significantly increased muscle layer thickness compared to the Con group (P < 0.05). Furthermore, in the C1.2 % group, there was a significant up-regulation of tight junction-related genes (claudin-14, occludin, zo-1) compared to the Con group (P < 0.05). 5-ethynyl-2'-deoxyuridine staining results also demonstrated a notable enhancement in intestinal cell proliferation within the C1.2 % group (P < 0.05). Regarding the intestinal chemical barrier, trypsin and lipase activities were significantly elevated in the C1.2 % group (P < 0.05), while hepcidin gene expression was considerably down-regulated in this group but up-regulated in the C1.8 % group (P < 0.05). In terms of the intestinal immune barrier, inflammation-related gene expression levels (tnf-α, il-1ß, caspase 9, ire1, perk, atf6) were markedly reduced in the C1.2 % group (P < 0.05). Regarding the intestinal biological barrier, the composition of the intestinal microbiota indicated that compared to the Con group, both the 0.6 % and 1.2 % groups showed a significant increase in Shannon index (P < 0.05). Additionally, there was a significant increase in the abundance of Firmicutes and Clostridium in the C1.2 % group (P < 0.05). In summary, supplementation of 1.2 % cholesterol in the plant-based diet exhibits the potential to enhance intestinal tight junction function and improve the composition of intestinal microbiota, thereby significantly promoting tilapia's intestinal health.

Multiple cis-regulatory elements control prox1a expression in distinct lymphatic vascular beds.

During embryonic development, lymphatic endothelial cell (LEC) precursors are distinguished from blood endothelial cells by the expression of Prospero-related homeobox 1 (Prox1), which is essential for lymphatic vasculature formation in mouse and zebrafish. Prox1 expression initiation precedes LEC sprouting and migration, serving as the marker of specified LECs. Despite its crucial role in lymphatic development, Prox1 upstream regulation in LECs remains to be uncovered. SOX18 and COUP-TFII are thought to regulate Prox1 in mice by binding its promoter region. However, the specific regulation of Prox1 expression in LECs remains to be studied in detail. Here, we used evolutionary conservation and chromatin accessibility to identify enhancers located in the proximity of zebrafish prox1a active in developing LECs. We confirmed the functional role of the identified sequences through CRISPR/Cas9 mutagenesis of a lymphatic valve enhancer. The deletion of this region results in impaired valve morphology and function. Overall, our results reveal an intricate control of prox1a expression through a collection of enhancers. Ray-finned fish-specific distal enhancers drive pan-lymphatic expression, whereas vertebrate-conserved proximal enhancers refine expression in functionally distinct subsets of lymphatic endothelium.

Large-language models facilitate discovery of the molecular signatures regulating sleep and activity.

Sleep, locomotor and social activities are essential animal behaviors, but their reciprocal relationships and underlying mechanisms remain poorly understood. Here, we elicit information from a cutting-edge large-language model (LLM), generative pre-trained transformer (GPT) 3.5, which interprets 10.2-13.8% of Drosophila genes known to regulate the 3 behaviors. We develop an instrument for simultaneous video tracking of multiple moving objects, and conduct a genome-wide screen. We have identified 758 fly genes that regulate sleep and activities, including mre11 which regulates sleep only in the presence of conspecifics, and NELF-B which regulates sleep regardless of whether conspecifics are present. Based on LLM-reasoning, an educated signal web is modeled for understanding of potential relationships between its components, presenting comprehensive molecular signatures that control sleep, locomotor and social activities. This LLM-aided strategy may also be helpful for addressing other complex scientific questions.

Elucidating the unexpected importance of intermediate-volatility organic compounds (IVOCs) from refueling procedure.

Evaporative emissions release organic compounds comparable to gasoline exhaust in China. However, the measurement of intermediate volatility organic compounds (IVOCs) is lacking in studies focusing on gasoline evaporation. This study sampled organics from a real-world refueling procedure and analyzed the organic compounds using comprehensive two-dimensional gas chromatography coupled with a mass spectrometer (GC×GC-MS). The non-target analysis detected and quantified 279 organics containing 93 volatile organic compounds (VOCs, 64.9 ± 7.4 % in mass concentration), 182 IVOCs (34.9 ± 7.4 %), and 4 semivolatile organic compounds (SVOCs, 0.2 %). The refueling emission profile was distinct from that of gasoline exhaust. The b-alkanes in the B12 volatility bin are the most abundant IVOC species (1.9 ± 1.4 µg m-3) in refueling. A non-negligible contribution of 17.5 % to the ozone formation potential (OFP) from IVOCs was found. Although IVOCs are less in concentration, secondary organic aerosol potential (SOAP) from IVOCs (58.1 %) even exceeds SOAP from VOCs (41.6 %), mainly from b-alkane in the IVOC range. At the molecular level, the proportion of cyclic compounds in SOAP (12.1 %) indeed goes above its mass concentration (3.1 %), mainly contributed by cyclohexanes and cycloheptanes. As a result, the concentrations and SOAP of cyclic compounds (>50 %) could be overestimated in previous studies. Our study found an unexpected contribution of IVOCs from refueling procedures to both ozone and SOA formation, providing new insights into secondary pollution control policy.

Synthesis and superconductivity in yttrium-cerium hydrides at high pressures.

Further increasing the critical temperature and/or decreasing the stabilized pressure are the general hopes for the hydride superconductors. Inspired by the low stabilized pressure associated with Ce 4f electrons in superconducting cerium superhydride and the high critical temperature in yttrium superhydride, we carry out seven independent runs to synthesize yttrium-cerium alloy hydrides. The synthetic process is examined by the Raman scattering and X-ray diffraction measurements. The superconductivity is obtained from the observed zero-resistance state with the detected onset critical temperatures in the range of 97-141 K. The upper critical field towards 0 K at pressure of 124 GPa is determined to be between 56 and 78 T by extrapolation of the results of the electrical transport measurements at applied magnetic fields. The analysis of the structural data and theoretical calculations suggest that the phase of Y0.5Ce0.5H9 in hexagonal structure with the space group of P63/mmc is stable in the studied pressure range. These results indicate that alloying superhydrides indeed can maintain relatively high critical temperature at relatively modest pressures accessible by laboratory conditions.

Characterizing NOx emissions from diesel trucks with tampered aftertreatment systems and its implications for identifying high emitters.

Reducing the differences between real-world and certificated NOx emission levels is an important element of in-use emission surveillance programs. Therefore, investigating the characteristics of the vehicles which have much higher NOx emissions (i.e., high-emitters) and determining a reasonable cut-off point to identify high-emitters with a low false detection rate is important. In this study, six diesel trucks were tested under different aftertreatment conditions. The results showed that the discrepancies of fuel-specific NOx emissions between vehicles with functioning and tampered selective catalytic reduction (SCR) systems occur mainly from medium- to high-speed modes. This is because the SCR systems were at low conversion efficiencies when the exhaust temperature was low, including cold-start and urban creep conditions. By using binary classification, we selected fuel-specific NOx cut-off points for high-emitters from China V and China VI diesel trucks. The false detection rate of high-emitters can decrease by 33 % and 95 %, if only NOx emissions from medium- to high-speed modes were used for the chosen cut-off points, respectively. This work highlights the importance of in-use emission compliance programs. It also suggests that high-emitters can be more accurately identified at medium- to high-speed modes if using instantaneous emission data.

Dietary supplementation of VA enhances growth, feed utilization, glucose and lipid metabolism, appetite, and antioxidant capacity of Chinese perch (Siniperca chuatsi).

The aim of this study was to investigate the effect of dietary vitamin A on juvenile Chinese perch (Siniperca chuatsi). Chinese perch were fed with five experimental diets containing 0, 20, 40, 60, and 80 mg VA·kg-1 for 8 weeks. Results showed that dietary vitamin A significantly influenced the fish's growth, feed utilization, glucose and lipid metabolism, appetite, and antioxidant capacity. Vitamin A-supplemented groups had higher weight gain rate (WGR) and specific growth rate (SGR) compared to the control group. Feed conversion ratio (FCR) was also lower in the vitamin A-supplemented groups. Dietary vitamin A had no significant effect on the survival rate (SR). Compared to the control group, fish fed with vitamin A had increased feed intake (FI), and the expression of appetite-promoting genes (npy and agrp) was significantly higher in the 40 mg VA·kg-1 group. Vitamin A also enhanced the utilization of dietary protein by Chinese perch. The serum glucose content of the fish fed with 40 mg VA·kg-1 diet was significantly higher than that of the control group and 20 mg VA·kg-1 diet, indicating that the promoting effect of VA on gluconeogenesis was greater than that on glycolysis. Additionally, dietary vitamin A increased the expression of lipid metabolism-related genes (hl and fas) and antioxidant genes (nrf2 and gpx) in the fish. These results suggest that the optimal vitamin A requirement of juvenile Chinese perch bream was estimated to be 37.32 mg VA·kg-1 based on broken-line regression analysis of WGR. In conclusion, this study provides valuable insights into the potential benefits of dietary vitamin A on the growth, metabolism, and antioxidant capacity of Chinese perch.

Alpha-Momorcharin, a type I ribosome inactivating protein, induced apoptosis of hepatocellular carcinoma SK-HEP-1 cells through mitochondrial pathway.

Alpha-Momorcharin (α-MMC), as one of the most important type I RIPs, has been reported to exert inhibitory effects against various tumour cells through its N-glycosidase activity. The present study was designed to propose an efficient purification strategy and explored its mechanism of apoptosis signalling pathway against human liver cancer cells SK-Hep-1. α-MMC can be successfully obtained by our purification strategy combining ion-exchange and gel-filtration chromatography. The functional studies revealed that α-MMC obviously increased the level of ROS and apoptosis rate, induced cell cycle arrest in the G1 phase, and depolarised MMP of SK-Hep-1 cells. To further confirm whether α-MMC could induce mitochondria involved apoptosis, we found that PARP-1, Caspase-3, Caspase-9, and BCL-2 were downregulated upon α-MMC. Taken together, these results suggested that this natural purified α-MMC can induce apoptosis involved mitochondria and may serve as a potential novel therapeutic drug in the treatment of human liver cancer in the future.

Synthesis of superconducting phase of La0.5Ce0.5H10at high pressures.

Clathrate hydrideFm3-m-LaH10has been proven as the most extraordinary superconductor with the critical temperatureTcabove 250 K upon compression of hundreds of GPa in recent years. A general hope is to reduce the stabilization pressure and maintain the highTcvalue of the specific phase in LaH10. However, strong structural instability distortsFm3-mstructure and leads to a rapid decrease ofTcat low pressures. Here, we investigate the phase stability and superconducting behaviors ofFm3-m-LaH10with enhanced chemical pre-compression through partly replacing La by Ce atoms from both experiments and calculations. For explicitly characterizing the synthesized hydride, we choose lanthanum-cerium alloy with stoichiometry composition of 1:1. X-ray diffraction and Raman scattering measurements reveal the stabilization ofFm3-m-La0.5Ce0.5H10in the pressure range of 140-160 GPa. Superconductivity withTcof 175 ± 2 K at 155 GPa is confirmed with the observation of the zero-resistivity state and supported by the theoretical calculations. These findings provide applicability in the future explorations for a large variety of hydrogen-rich hydrides.

Simultaneous extraction and detection of peptides, steroids, and proteins in small tissue samples.

The detection and quantification of hormones are important to assess the reproductive and stress status of experimental models and for the diagnosis of diseases in human and veterinary clinics. Traditionally, steroid, peptide, and protein hormones are analyzed in individual experiments using different extraction methodologies. With the new advancement on HPLC sorbents, the simultaneous measurement of hormones from different categories becomes possible. In this study, we present a novel sample processing strategy for the simultaneous extraction and detection of peptides, steroids, and proteins using high-resolution liquid chromatography tandem mass spectrometry. We demonstrate the sensitivity of our method for small tissues by acquiring data from brain, pituitary gland, and gonads of single zebrafish samples. This approach promises to shed light on the hormonal pathways and their interrelationships, providing knowledge on the integration of hormone systems.

Coexistent, Competing Tunnelling, and Hopping Charge Transport in Compressed Metal Nanocluster Crystals.

Understanding charge transport among metal particles with sizes of approximately 1 nm poses a great challenge due to the ultrasmall nanosize, yet it holds great significance in the development of innovative materials as substitutes for traditional semiconductors, which are insulative and unstable in less than ∼10 nm thickness. Herein, atomically precise gold nanoclusters with well-defined compositions and structures were investigated to establish a mathematical relation between conductivity and interparticle distance. This was accomplished using high-pressure in situ resistance characterizations, synchrotron X-ray diffraction (XRD), and the Murnaghan equation of state. Based on this precise correlation, it was predicted that the conductivity of Au25(SNap)18 (SNap: 1-naphthalenethiolate) solid is comparable to that of bulk silver when the interparticle distance is reduced to approximately 3.6 Å. Furthermore, the study revealed the coexisting, competing tunneling, and incoherent hopping charge transport mechanisms, which differed from those previously reported. The introduction of conjugation-structured ligands, tuning of the structures of metal nanoclusters, and use of high-pressure techniques contributed to enhanced conductivity, and thus, the charge carrier types were determined using Hall measurements. Overall, this study provides valuable insight into the charge transport in gold nanocluster solids and represents an important advancement in metal nanocluster semiconductor research.