Rewiring of the Fruit Metabolome in Tomato Breeding.

Humans heavily rely on dozens of domesticated plant species that have been further improved through intensive breeding. To evaluate how breeding changed the tomato fruit metabolome, we have generated and analyzed a dataset encompassing genomes, transcriptomes, and metabolomes from hundreds of tomato genotypes. The combined results illustrate how breeding globally altered fruit metabolite content. Selection for alleles of genes associated with larger fruits altered metabolite profiles as a consequence of linkage with nearby genes. Selection of five major loci reduced the accumulation of anti-nutritional steroidal glycoalkaloids in ripened fruits, rendering the fruit more edible. Breeding for pink tomatoes modified the content of over 100 metabolites. The introgression of resistance genes from wild relatives in cultivars also resulted in major and unexpected metabolic changes. The study reveals a multi-omics view of the metabolic breeding history of tomato, as well as provides insights into metabolome-assisted breeding and plant biology.

One-Dimensional Crystal-Structure Te-Se Alloy for Flexible Shortwave Infrared Photodetector and Imaging.

Flexible shortwave infrared detectors play a crucial role in wearable devices, bioimaging, automatic control, etc. Commercial shortwave infrared detectors face challenges in achieving flexibility due to the high fabrication temperature and rigid material properties. Herein, we develop a high-performance flexible Te0.7Se0.3 photodetector, resulting from the unique 1D crystal structure and small elastic modulus of Te-Se alloying. The flexible photodetector exhibits a broad-spectrum response ranging from 365 to 1650 nm, a fast response time of 6 µs, a broad linear dynamic range of 76 dB, and a specific detectivity of 4.8 × 1010 Jones at room temperature. The responsivity of the flexible detector remains at 93% of its initial value after bending with a small curvature of 3 mm. Based on the optimized flexible detector, we demonstrate its application in shortwave infrared imaging. These results showcase the great potential of Te0.7Se0.3 photodetectors for flexible electronics.

Low-threshold AlGaN-based deep ultraviolet laser enabled by a nanoporous cladding layer.

We demonstrated an AlGaN-based multiple-quantum-well (MQW) deep ultraviolet (DUV) laser at 278 nm using a nanoporous (NP) n-AlGaN as the bottom cladding layer grown on the sapphire substrate. The laser has a very-low-threshold optically pumped power density of 79 kW/cm2 at room temperature and a transverse electric (TE)-polarization-dominant emission. The high optical confinement factor of 9.12% benefiting from the low refractive index of the nanoporous n-AlGaN is the key to enable a low-threshold lasing. The I-V electrical measurement demonstrates that an ohmic contact can be still achieved in the NP n-AlGaN with a larger but acceptable resistance, which indicates it is compatible with electrically driven laser devices. Our work provides insights into the design and fabrication of low-threshold lasers emitting in the DUV regime.

Substrate engineering for wafer-scale two-dimensional material growth: strategies, mechanisms, and perspectives.

The fabrication of wafer-scale two-dimensional (2D) materials is a prerequisite and important step for their industrial applications. Chemical vapor deposition (CVD) is the most promising approach to produce high-quality films in a scalable way. Recent breakthroughs in the epitaxy of wafer-scale single-crystalline graphene, hexagonal boron nitride, and transition-metal dichalcogenides highlight the pivotal roles of substrate engineering by lattice orientation, surface steps, and energy considerations. This review focuses on the existing strategies and underlying mechanisms, and discusses future directions in epitaxial substrate engineering to deliver wafer-scale 2D materials for integrated electronics and photonics.

Green manufacturing for achieving carbon neutrality goal requires innovative technologies: A bibliometric analysis from 1991 to 2022.

Recent years have seen a significant increase in interest in green manufacturing as a key driver of global carbon-neutral efforts and sustainable development. To find the research hotspots of green manufacturing and reveal future research trends, this study reviewed and analyzed research articles from the Web of Science database on green manufacturing from 1991 to 2022 using a bibliometric method. The findings indicate a significant rise in the number of articles related to green manufacturing since the 2010s. Moreover, there has been an increase in the involvement of scholars from developing countries such as China and India in this field. Based on the literature review and bibliometric cluster analysis on green manufacturing, we believed that future research may continue following the lines of intelligent technology integration, adoption of frontier engineering techniques, and industry development in line with carbon reduction targets. A framework for future green manufacturing development is proposed, with a focus on Chinese policies. The framework could provide policy implications for developing countries looking to pursue opportunities for development in green manufacturing.

Patients' attitudes regarding genetic counseling before germline BRCA1/2 pathogenic variants testing in Taiwan: A single-country, multi-center, patient-reported outcome study.

Germline pathogenic variants of BRCA1 or BRCA2 cause hereditary breast and ovarian cancer syndromes. The present study investigated the participants' understanding and awareness of germline BRCA1/2 pathogenic variants before genetic counseling, the expectations and obstacles for genetic testing from the perspective of participants and their families, and their attitudes towards genetic testing after counseling. In this single-country, multicenter, non-interventional, patient-reported outcome study, untested cancer patients and their families who visited genetic counseling clinics or who wanted to receive pre-test genetic counseling were eligible to fill in the questionnaire after pre-test counseling for germline BRCA1/2 testing. Demographic information, clinical characteristics, and information collected from the questionnaires, including the understanding of BRCA1/2 pathogenic variants before genetic counseling, understanding of BRCA1/2 pathogenic variants and feelings after genetic counseling, willingness to share results of genetic testing with family, and willingness to receive genetic testing, were summarized using descriptive statistics. A total of 88 participants were enrolled. The proportion of slight understanding of BRCA1/2 pathogenic variants increased from 11.4% to 67.0%, and the proportion of full understanding increased from 0% to 8.0%. After genetic counseling, most participants were willing to undergo genetic testing (87.5%) and share the results with their families (96.6%). The main factors that may affect participants' willingness to undergo BRCA1/2 testing were management (61.2%) and testing costs (25.9%). After pre-test counseling, there was a high acceptance of BRCA1/2 testing and in-family information sharing in Taiwanese patients with cancer and their families, which may serve as a reference for implementing genetic counseling in Taiwan.

Sustainable development trial undertaking: Experience from China's innovation demonstration zones.

In December 2016, China proposed creating about ten sustainable development demonstration zones to create a batch of replicable and extendable demonstration models to fully realize the 2030 sustainable development goals (SDGs) and provide a reference for similar regions of emerging economies. It has now approved six cities that act as green and low carbon lifestyle laboratories. However, very few documents quantitatively evaluate this policy's natural, economic, and social impact. This article comprehensively uses dynamic stochastic general equilibrium (DSGE) methods and input-output methods to portray the urgency of sustainable development in China. This article sets the sustainable indicator system for the approved six cities and sets scenario simulations based on transformation needs for quantitative evaluation. The results show that demonstration zones policies would lead to a decline in the output of heavily polluting industries. However, in China's current coal-dominated energy structure, the degree of positive impact on the growth of clean industry output would be less than the intensity of the impact on heavily polluting industries.

Elevated Preoperative NMPR Predicts an Unfavorable Chance of Survival in Resectable Esophageal Squamous Cell Carcinoma.

Background and objectives: Combined peripheral neutrophil−platelet indexes reflecting the systemic inflammatory status have been reported to predict the clinical outcome in patients with various types of cancer. However, the prognostic value of combined neutrophil−platelet indexes in operable esophageal squamous cell carcinoma (ESCC) remains unclear. The study introduced a novel combined neutrophil−meanplateletvolume−platelet ratio (NMPR) index and investigated its clinical and prognostic value in patients with operable ESCC receiving curative surgery. Materials and Methods: A retrospective analysis of the clinicopathologic data of 277 consecutive ESCC patients who received curative resection at Zhejiang Cancer Hospital in China between January 2007 and December 2010 was conducted (the training cohort). In addition, the clinicopathologic data of 101 resectable ESCC patients at Renmin Hospital of Hubei University of Medicine between December 2018 and June 2021 were collected (the external validation cohort). The optimal cutoff value of NMPR concerning overall survival (OS) in the training cohort was determined by X-tile software. Univariate and multivariate Cox regression analyses were used to evaluate the prognostic value of NMPR along with other variables in the training cohort, which was further validated with the same cutoff value in the external validation cohort. Significant predictors of OS were used to construct the nomogram, of which the discrimination and calibration was evaluated by concordance index (C-index) and calibration plots. Results: With a cutoff value of 16.62, the results from both the training and external validation cohorts supported the association of high NMPR (>16.62) with increased tumor length and advanced T stage but not with other variables. In the training cohort, a significant association between shorter OS and high NMPR (p = 0.04) as well as high CRP (p < 0.001), poor tumor differentiation (p = 0.008), advanced T stage (p = 0.006), advanced N stage (p < 0.001) and high CEA (p = 0.007) was revealed. Additionally, the high NMPR was verified to independently predict unfavorable OS (p = 0.049) in the external validation cohort. The C-index of the OS nomogram cooperating significant predictors in the training cohort was 0.71 and the calibration plots of the OS nomogram fitted well. Conclusions: The present study demonstrates that high NMPR is an independent predictor of unfavorable OS in resectable ESCC patients without neoadjuvant therapy.

Facile Benzylic Alkylation of Arenes with Alcohols by Catalysis with Spirocyclic NHC IrIII Pincer Complex.

A facile benzylic alkylation of indenes and other arenes was developed from readily available primary and secondary alcohols using our newly investigated CCC pincer IrIII catalyst (SNIr-H). Excellent regioselectivity and yield (89 %) of the C3-alkylated indenes were obtained. Additionally, the challenging sp2 C-alkylation was readily accomplished. This method could be utilized for the synthesis of the analogs of a histamine H1 receptor antagonist and the functional material template molecule, indeno[2,1-a]indene. A hemilabile IrIII -dihydride intermediate was proposed based on control experiments and previous density functional theory (DFT) calculations for the borrowing hydrogen mechanism and is key to the success of this IrIII catalyst in the reduction of unactivated multi-substituted olefin intermediates.

Extrinsic Photoconduction Induced Short-Wavelength Infrared Photodetectors Based on Ge-Based Chalcogenides.

2D layered photodetectors have been widely researched for intriguing optoelectronic properties but their application fields are limited by the bandgap. Extending the detection waveband can significantly enrich functionalities and applications of photodetectors. For example, after breaking through bandgap limitation, extrinsic Si photodetectors are used for short-wavelength infrared or even long-wavelength infrared detection. Utilizing extrinsic photoconduction to extend the detection waveband of 2D layered photodetectors is attractive and desirable. However, extrinsic photoconduction has yet not been observed in 2D layered materials. Here, extrinsic photoconduction-induced short-wavelength infrared photodetectors based on Ge-based chalcogenides are reported for the first time and the effectiveness of intrinsic point defects are demonstrated. The detection waveband of room-temperature extrinsic GeSe photodetectors with the assistance of Ge vacancies is broadened to 1.6 µm. Extrinsic GeSe photodetectors have an excellent external quantum efficiency (0.5%) at the communication band of 1.31 µm and polarization-resolved capability to subwaveband radiation. Moreover, room-temperature extrinsic GeS photodetectors with a detection waveband to the communication band of 1.55 µm further verify the versatility of intrinsic point defects. This approach provides design strategies to enrich the functionalities of 2D layered photodetectors.

Substitutionally Doped MoSe2 for High-Performance Electronics and Optoelectronics.

2D materials, of which the carrier type and concentration are easily tuned, show tremendous superiority in electronic and optoelectronic applications. However, the achievements are still quite far away from practical applications. Much more effort should be made to further improve their performance. Here, p-type MoSe2 is successfully achieved via substitutional doping of Ta atoms, which is confirmed experimentally and theoretically, and outstanding homojunction photodetectors and inverters are fabricated. MoSe2 p-n homojunction device with a low reverse current (300 pA) exhibits a high rectification ratio (104 ). The analysis of dark current reveals the domination of the Shockley-Read-Hall (SRH) and band-to-band tunneling (BTB) current. The homojunction photodetector exhibits a large open-circuit voltage (0.68 V) and short-circuit currents (1 µA), which is suitable for micro-solar cells. Furthermore, it possesses outstanding responsivity (0.28 A W-1 ), large external quantum efficiency (42%), and a high signal-to-noise ratio (≈107 ). Benefiting from the continuous energy band of homojunction, the response speed reaches up to 20 µs. Besides, the Ta-doped MoSe2 inverter exhibits a high voltage gain (34) and low power consumption (127 nW). This work lays a foundation for the practical application of 2D material devices.

Extended infrared responses in Er/O-hyperdoped Si at room temperature.

Silicon photonics has become the preferred candidate for technologies applicable to multifarious fields. However, the applications are strictly limited by the intrinsic in-band photo effect of silicon. Herein, near-infrared photodetectors that break through the silicon bandgap by Er/O hyperdoping are fabricated, potentially extending their applications into telecommunications, low-light-level night vision, medical treatment, and others. Er/O-hyperdoped silicon was achieved as an infrared light absorption layer through ion implantation. The lattice damage caused by ion implantation was repaired by a deep cooling process in which high-temperature samples were cooled by helium flushing cooled by liquid nitrogen. Traditional junction and metallization processes were performed to form a photodiode. We demonstrate that the device has a spectral range up to the wavelength of 1568 nm, a maximum responsivity of 165 µA/W at 1310 nm, and 3 dB cutoff bandwidth up to 3 kHz. Finally, temperature-dependent optical-electrical characteristics were measured to demonstrate the activation mechanism of Er/O in silicon. This Letter proves silicon's potential in realizing extended infrared detection at room temperature, and it provides a possible way to fabricate infrared optoelectronics and signal processing integrated chips on a CMOS (complementary metal-oxide-semiconductor) platform.

Purely laparoscopic feeding jejunostomy: a procedure which deserves more attention.

BACKGROUND: Laparoscopic procedure has inherent merits of smaller incisions, better cosmesis, less postoperative pain, and earlier recovery. In the current study, we presented our method of purely laparoscopic feeding jejunostomy and compared its results with that of conventional open approach. METHODS: We retrospectively reviewed our patients from 2012 to 2019 who had received either laparoscopic jejunostomy (LJ, n = 29) or open ones (OJ, n = 94) in Chang Gung Memorial Hospital, Linkou. Peri-operative data and postoperative outcomes were analyzed. RESULTS: In the current study, we employed 3-0 Vicryl, instead of V-loc barbed sutures, for laparoscopic jejunostomy. The mean operative duration of LJ group was about 30 min longer than the OJ group (159 ± 57.2 mins vs 128 ± 34.6 mins; P = 0.001). There were no intraoperative complications reported in both groups. The patients in the LJ group suffered significantly less postoperative pain than in the OJ group (mean NRS 2.03 ± 0.9 vs. 2.79 ± 1.2; P = 0.002). The majority of patients in both groups received early enteral nutrition (< 48 h) after the operation (86.2% vs. 74.5%; P = 0.143). CONCLUSIONS: Our study demonstrated that purely laparoscopic feeding jejunostomy is a safe and feasible procedure with less postoperative pain and excellent postoperative outcome. It also provides surgeons opportunities to enhance intracorporeal suture techniques.

[Down-regulation of miR-488 targeting to promote Jag1 expression inhibits hypoxia-reoxygenation myocardial H9c2 cell damage].

OBJECTIVE: To study the effect of down-regulating miR-488 targeting Jag1 on the injury of hypoxia-reoxygenation myocardial H9c2 cells. METHODS: A hypoxic-reoxygenated myocardial H9c2 cell injury model was constructed. miR-488 inhibitor was used to transfect the cells. CCK-8 method and flow cytometry were used to detect cell proliferation and apoptosis in each group. Lactate dehydrogenase (LDH), superoxide dismutase (SOD), malonaldehyde (MDA), catalase (CAT) levels were detected. Western blotting was used to detect the expression of Bcl-2 associated X Protein (Bax) and B cell lymphoma/lewkmia-2 (Bcl-2). Target genes of miR-488 were predicted, and a luciferase reporter system was used to verify the targeting relationship between the two. Myocardial H9c2 cells were co-transfected with miR-488 inhibitor and Jag1 siRNA, and treated with hypoxia and reoxygenation, cell proliferation, apoptosis, LDH, SOD, MDA, CAT levels, and Bax, Bcl-2 protein expression were detected. RESULTS: The expression of miR-488 in the hypoxia-reoxygenated myocardial H9c2 cells was increased, along with reduced cell proliferation, increased apoptosis, increased Bax protein expression, decreased Bcl-2 protein expression, increased MDA, decreased CAT and SOD, and increased LDH level in the supernatant of cell culture. When myocardial H9c2 cells were transfected with miR-488 inhibitor and treated with hypoxia and reoxygenation, the expression of miR-488 was decreased, along with increased cell proliferation, decreased apoptosis, decreased Bax protein expression, increased Bcl-2 protein expression, decreased MDA, increased CAT and SOD, and decreased LDH level in the supernatant of cell culture. Down-regulation of miR-488 could target and down-regulate Jag1 expression. And Jag1 siRNA could reverse the effect of miR-488 inhibitor on the proliferation, apoptosis, LDH, SOD, MDA, CAT levels and the expression of Bax and Bcl-2 of hypoxic-reoxygenated myocardial H9c2 cells. CONCLUSION: Down-regulating miR-488 targeted Jag1 can attenuate hypoxia-reoxygenation induced myocardial H9c2 cell injury.

A review on analytical methods for pharmaceutical and personal care products and their transformation products.

Pharmaceutical and personal care products (PPCPs) and corresponding transformation products have caused widespread concern due to their persistent emissions and potential toxicity. They have wide octanol-water partition coefficients (Kow) and different ionization constants (pKa) resulting in a poor analysis accuracy and efficiency. A suitable analytical method is the first prerequisite for further research on their environmental behavior to prioritize the substances. This study reviewed a full-scale analytical protocol for environmental samples in the recent ten years: from sampling to instrumental methods. Passive sampling techniques were compared and recommended for long-term continuous and scientific observation. A quick and effective sample extraction and clean-up method are highly required. Chromatographic methods coupled to mass spectrometry for determining PPCPs with a wide range of logKow (-7.53 to 10.80) were summed up. High-resolution mass spectrometry was confirmed to be a promising strategy for screening unknown transformation products, which would provide a nanogram level of detection limits and more accurate mass resolution. Screening strategies and mass change principles were summarized in detail. The recovery rate was important in multiple contaminants analysis identification and factors affecting the recovery rate of PPCPs were also discussed in this review, including sample matrix, target compounds characteristics, extraction method and solid-phase adsorbent. This review provides useful information for the selection of appropriate analytical methods and future development directions.

Quantitative three-dimensional nondestructive imaging of whole anaerobic ammonium-oxidizing bacteria.

Anaerobic ammonium-oxidizing (anammox) bacteria play a key role in the global nitrogen cycle and in nitrogenous wastewater treatment. The anammox bacteria ultrastructure is unique and distinctly different from that of other prokaryotic cells. The morphological structure of an organism is related to its function; however, research on the ultrastructure of intact anammox bacteria is lacking. In this study, in situ three-dimensional nondestructive ultrastructure imaging of a whole anammox cell was performed using synchrotron soft X-ray tomography (SXT) and the total variation-based simultaneous algebraic reconstruction technique (TV-SART). Statistical and quantitative analyses of the intact anammox bacteria were performed. High soft X-ray absorption composition inside anammoxosome was detected and verified to be relevant to iron-binding protein. On this basis, the shape adaptation of the anammox bacteria response to iron was explored.

The association between immune-related adverse events and survival outcomes in Asian patients with advanced melanoma receiving anti-PD-1 antibodies.

BACKGROUND: The association between immune-related adverse events (irAEs) and survival outcomes in patients with advanced melanoma receiving therapy with immune checkpoint inhibitors (ICIs) has not been well established, particularly in Asian melanoma. METHODS: We retrospectively reviewed 49 melanoma patients undergoing therapy with ICIs (anti-PD-1 monotherapy), and analyzed the correlation between irAEs and clinical outcomes including progression-free survival (PFS) and overall survival (OS). RESULTS: Overall, the patients who experienced grade 1-2 irAEs had longer PFS (median PFS, 4.6 vs. 2.5 months; HR, 0.52; 95% CI: 0.27-0.98; p = 0.042) and OS (median OS, 15.2 vs. 5.7 months; HR, 0.50; 95% CI: 0.24-1.02; p = 0.058) than the patients who did not experience irAEs. Regarding the type of irAE, the patients with either skin/vitiligo or endocrine irAEs showed better PFS (median PFS, 6.1 vs. 2.7 months; HR, 0.40, 95% CI: 0.21-0.74; p = 0.003) and OS (median OS, 18.7 vs. 4.5 months; HR, 0.34, 95% CI: 0.17-0.69, p = 0.003) than patients without any of these irAEs. CONCLUSIONS: Melanoma patients undergoing anti-PD-1 monotherapy and experiencing mild-to-moderate irAEs (grade 1-2), particularly skin (vitiligo)/endocrine irAEs had favorable survival outcomes. Therefore, the association between irAEs and the clinical outcomes in melanoma patients undergoing anti-PD-1 ICIs may be severity and type dependent.

Photogating-controlled ZnO photodetector response for visible to near-infrared light.

In recent years, as a direct wide band gap semiconductor, zinc oxide (ZnO) nanomaterial has attracted a lot of attention. However, the widely investigated ZnO materials are strongly limited in fast-response and broadband photodetectors due to their inherent weaknesses, so an effective structure or mechanism of ZnO nanostructure photodetector is greatly needed. In this work, a photogating-controlled photodetector based on a ZnO nanosheet-HfO2-lightly doped Si architecture is demonstrated. Its performance was significantly improved by the photogating-controlled local field at the Si and HfO2 interfaces compared to the findings in other published works on ZnO. Consequently, the photodetector not only effectively balances the responsivity (as high as 5.6 A W-1) and response time (400 µs), but also broadens the wavelength response of the ZnO-based photodetectors from visible to near-infrared light range (~1200 nm). Additionally, the photogating-controlled ZnO photodetector enables high-resolution imaging both in the visible and near-infrared bands. Our photogating-controlled ZnO photodetectors not only exemplify the controllability of the gate electrode in high mobility materials but also provide a basis for the development of fast speed and high responsivity detection of high mobility materials.

Ultrahigh Hole Mobility of Sn-Catalyzed GaSb Nanowires for High Speed Infrared Photodetectors.

Owing to the relatively low hole mobility, the development of GaSb nanowire (NW) electronic and photoelectronic devices has stagnated in the past decade. During a typical catalyst-assisted chemical vapor deposition (CVD) process, the adopted metallic catalyst can be incorporated into the NW body to act as a slight dopant, thus regulating the electrical properties of the NW. In this work, we demonstrate the use of Sn as a catalyst and dopant for GaSb NWs in the surfactant-assisted CVD growth process. The Sn-catalyzed zinc-blende GaSb NWs are thin, long, and straight with good crystallinity, resulting in a record peak hole mobility of 1028 cm2 V-1 s-1. This high mobility is attributed to the slight doping of Sn atoms from the catalyst tip into the NW body, which is verified by the red-shifted photoluminescence peak of Sn-catalyzed GaSb NWs (0.69 eV) compared with that of Au-catalyzed NWs (0.74 eV). Furthermore, the parallel array NWs also show a high peak hole mobility of 170 cm2 V-1 s-1, a high responsivity of 61 A W-1, and fast rise and decay times of 195.1 and 380.4 µs, respectively, under the illumination of 1550 nm infrared light. All of the results demonstrate that the as-prepared Sn-catalyzed GaSb NWs are promising for application in next-generation electronics and optoelectronics.

Effects of N-acetylcysteine on the energy status and antioxidant capacity in heart and liver of cold-stressed broilers.

OBJECTIVE: Cold stress induces oxidative damage and impairs energy status of broilers. N-acetylcysteine (NAC) exhibits antioxidant properties and modulates energy metabolism of animals. This study was conducted to investigate the effects of NAC on energy status and antioxidant capacity of heart and liver in the cold-stressed broilers. METHODS: The experiment consisted of 4 treatments in a 2×2 factorial arrangement with two diets (basal diet or plus 0.1% NAC) and two ambient temperatures (thermoneutral [conventional ambient temperature] or cold stress [10°C±1°C during days 15 to 42]). RESULTS: No ascites were seen in cold-stressed broilers. NAC did not attenuate the impaired growth performance of stressed birds. However, NAC decreased plasma asparagine but increased aspartate levels in cold-stressed birds (p<0.05). NAC reduced hepatic adenosine triphosphate (ATP) but elevated adenosine diphosphate contents in unstressed birds (p< 0.05). The hepatic ratio of adenosine monophosphate (AMP) to ATP was increased in birds fed NAC (p<0.05). NAC decreased plasma malondialdehyde (MDA) level and cardiac total superoxide dismutase (T-SOD) activity in unstressed birds, but increased hepatic activities of T-SOD, catalase and glutathione peroxidase in stressed birds (p<0.05). NAC down-regulated hepatic AMP-activated protein kinase but up-regulated cardiac heme-oxigenase mRNA expression in stressed birds, and decreased expression of hepatic peroxisome proliferatoractivated receptor coactivator-1α as well as hypoxia-inducible factor-1α in liver and heart of birds. CONCLUSION: Dietary NAC did not affect energy status but enhanced the hepatic antioxidant capacity by increasing the activities of antioxidant enzymes in cold-stressed broilers.