1
|
Pszczolkowski VL, Connelly MK, Hoppman A, Benn AD, Laporta J, Hernandez LL, Arriola Apelo SI. Intravenous infusion of 5-hydroxytryptophan to mid-lactation Holstein cows transiently affects milk production and circulating amino acid concentrations. J Dairy Sci 2024; 107:3306-3318. [PMID: 38101740 DOI: 10.3168/jds.2023-23934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 11/17/2023] [Indexed: 12/17/2023]
Abstract
In dairy cows, the lactating mammary glands synthesize serotonin, which acts in an autocrine-paracrine manner in the glands and is secreted into the periphery. Serotonin signaling during lactation modulates nutrient metabolism in peripheral tissues such as adipose and liver. We hypothesized that the elevation of circulating serotonin during lactation would increase nutrient partitioning to the mammary glands, thereby promoting milk production. Our objective was to elevate circulating serotonin via intravenous infusion of the serotonin precursor 5-hydroxytryptophan (5-HTP) to determine its effects on mammary supply and extraction efficiency of AA, and milk components production. Twenty-two multiparous mid-lactation Holstein cows were intravenously infused with 5-HTP (1 mg/kg body weight) or saline, in a crossover design with two 21-d periods. Treatments were infused via jugular catheters for 1 h/d, on d 1 to 3, 8 to 10, and 15 to 17 of each period, to maintain consistent elevation of peripheral serotonin throughout the period. Milk and blood samples were collected in the last 96 h of each period. Whole-blood serotonin concentration was elevated above saline control for 96 h after the last 5-HTP infusion. Dry matter intake was decreased for cows receiving 5-HTP, and on average they lost body weight over the 21-d period, in contrast to saline cows who gained body weight. Milk production and milk protein yield were lower in cows receiving 5-HTP during the 3 infusion days, but both recovered to saline cow yields in the days after. Although milk fat yield exhibited a day-by-treatment interaction, no significant difference occurred on any given day. Milk urea nitrogen concentration was lower in 5-HTP cows on the days following the end of infusions, but not different from saline cows on infusion days. Meanwhile, plasma urea nitrogen was not affected by 5-HTP infusion. Circulating concentrations of AA were overall transiently decreased by 5-HTP, with concentrations mostly returning to baseline within 7 h after the end of 5-HTP infusion. Mammary extraction efficiency of AA was unaffected by 5-HTP infusion. Overall, both lactation performance and circulating AA were transiently reduced in cows infused with 5-HTP, despite sustained elevation of circulating serotonin concentration.
Collapse
Affiliation(s)
- Virginia L Pszczolkowski
- Department of Animal and Dairy Sciences, University of Wisconsin-Madison, Madison, WI 53706; Endocrinology and Reproductive Physiology Graduate Training Program, University of Wisconsin-Madison, Madison, WI 53706
| | - Meghan K Connelly
- Department of Animal and Dairy Sciences, University of Wisconsin-Madison, Madison, WI 53706
| | - August Hoppman
- Department of Animal and Dairy Sciences, University of Wisconsin-Madison, Madison, WI 53706
| | - Amara D Benn
- Department of Animal and Dairy Sciences, University of Wisconsin-Madison, Madison, WI 53706
| | - Jimena Laporta
- Department of Animal and Dairy Sciences, University of Wisconsin-Madison, Madison, WI 53706; Endocrinology and Reproductive Physiology Graduate Training Program, University of Wisconsin-Madison, Madison, WI 53706
| | - Laura L Hernandez
- Department of Animal and Dairy Sciences, University of Wisconsin-Madison, Madison, WI 53706; Endocrinology and Reproductive Physiology Graduate Training Program, University of Wisconsin-Madison, Madison, WI 53706
| | - Sebastian I Arriola Apelo
- Department of Animal and Dairy Sciences, University of Wisconsin-Madison, Madison, WI 53706; Endocrinology and Reproductive Physiology Graduate Training Program, University of Wisconsin-Madison, Madison, WI 53706.
| |
Collapse
|
2
|
Ding L, Shen Y, Jawad M, Wu T, Maloney SK, Wang M, Chen N, Blache D. Effect of arginine supplementation on the production of milk fat in dairy cows. J Dairy Sci 2022; 105:8115-8129. [PMID: 35965125 DOI: 10.3168/jds.2021-21312] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 05/25/2022] [Indexed: 11/19/2022]
Abstract
Arginine, one of the conditionally essential AA, has been reported to affect fat synthesis and metabolism in nonruminant animals by influencing adenosine monophosphate activated protein kinase (AMPK) in some organs. In dairy cows, the effect of Arg on milk fat production is not clear, and any potential mechanism that underlies the effect is unknown. We tested the hypothesis that Arg infusion would improve the production of milk fat, and explored possible mechanism that might underlie any effect. We used 6 healthy lactating cows at 20 ± 2 d in milk, in fourth parity, with a body weight of 508 ± 14 kg, body condition score of 3.0 ± 0, and a milk yield of 30.6 ± 1.8 kg/d (mean ± standard deviation). The cows were blocked by days in milk and milk yield and each cow received 3 treatments in a replicated 3 × 3 Latin square design, with each of the experimental periods lasting 7 d with a 14-d washout between each period. The treatments, delivered in random order, were (1) infusion of saline (control); (2) infusion of 0.216 mol/d of l-Arg in saline (Arg); (3) infusion of 0.868 mol/d of l-Ala in saline (the Arg and Ala treatments were iso-nitrogenous) through a jugular vein. On the last day of each experimental period, blood was sampled to measure insulin, nitric oxide, glucose, and nonesterified fatty acid, and the liver and mammary gland were biopsied to measure the expression of genes. Milk yield was recorded, and milk fat percentage was measured daily during each of the experimental periods. The yield and composition of fatty acid (FA) in milk was measured daily on the last 3 d during each of the experimental periods. The data were analyzed using a mixed model with treatment as a fixed factor, and cow, period, and block as random factors. The daily milk yield and milk fat yield when the cows were infused with Arg were 2.2 kg and 76 g, respectively, higher than that in control, and 1.8 kg and 111 g, respectively, higher than that in Ala. When the cows were infused with Arg they had higher concentration and yield of de novo synthesized FA, than when they received the control or Ala infusions, although milk fat percentage, daily feed intake, and the digestibility of nutrients were not affected by treatment. The serum concentration of nitric oxide and insulin were higher during Arg than during control or Ala, with no difference between control and Ala. In the liver, the expression of the genes coding for AMPK (PRKAA1, PRKAB1, and PRKAG1) and genes related to the oxidation of FA were higher during Arg than during control or Ala, whereas in the mammary gland the expression PRKAB1 was lowest, and the expression of genes involved in the synthesis of milk fat were highest, during Arg infusion. The results suggest the intravenous infusion of Arg enhanced the production of milk fat by promoting the de novo synthesis of FA and increasing milk yield.
Collapse
Affiliation(s)
- L Ding
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, Jiangsu, P.R. China; State Key Laboratory of Sheep Genetic Improvement and Healthy Production, Xinjiang Academy of Agricultural Reclamation Sciences, Shihezi, 832000, P.R. China; UWA Institute of Agriculture, The University of Western Australia, Perth 6009, WA, Australia; School of Agriculture and Environment, The University of Western Australia, Perth 6009, WA, Australia
| | - Y Shen
- College of Animal Science and Technology, Hebei Agricultural University, Baoding 071001, Hebei, P.R. China
| | - M Jawad
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, Jiangsu, P.R. China
| | - T Wu
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, Jiangsu, P.R. China
| | - S K Maloney
- UWA Institute of Agriculture, The University of Western Australia, Perth 6009, WA, Australia; School of Human Sciences, The University of Western Australia, Perth 6009, WA, Australia
| | - M Wang
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, Jiangsu, P.R. China; State Key Laboratory of Sheep Genetic Improvement and Healthy Production, Xinjiang Academy of Agricultural Reclamation Sciences, Shihezi, 832000, P.R. China.
| | - N Chen
- State Key Laboratory of Sheep Genetic Improvement and Healthy Production, Xinjiang Academy of Agricultural Reclamation Sciences, Shihezi, 832000, P.R. China.
| | - D Blache
- UWA Institute of Agriculture, The University of Western Australia, Perth 6009, WA, Australia; School of Agriculture and Environment, The University of Western Australia, Perth 6009, WA, Australia.
| |
Collapse
|
3
|
Li Z, Lei X, Chen X, Yin Q, Shen J, Yao J. Long-term and combined effects of N-[2-(nitrooxy)ethyl]-3-pyridinecarboxamide and fumaric acid on methane production, rumen fermentation, and lactation performance in dairy goats. J Anim Sci Biotechnol 2021; 12:125. [PMID: 34865657 PMCID: PMC8647438 DOI: 10.1186/s40104-021-00645-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 10/26/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In recent years, nitrooxy compounds have been identified as promising inhibitors of methanogenesis in ruminants. However, when animals receive a nitrooxy compound, a high portion of the spared hydrogen is eructated as gas, which partly offsets the energy savings of CH4 mitigation. The objective of the present study was to evaluate the long-term and combined effects of supplementation with N-[2-(nitrooxy)ethyl]-3-pyridinecarboxamide (NPD), a methanogenesis inhibitor, and fumaric acid (FUM), a hydrogen sink, on enteric CH4 production, rumen fermentation, bacterial populations, apparent nutrient digestibility, and lactation performance of dairy goats. RESULTS Twenty-four primiparous dairy goats were used in a randomized complete block design with a 2 × 2 factorial arrangement of treatments: supplementation without or with FUM (32 g/d) or NPD (0.5 g/d). All samples were collected every 3 weeks during a 12-week feeding experiment. Both FUM and NPD supplementation persistently inhibited CH4 yield (L/kg DMI, by 18.8% and 18.1%, respectively) without negative influence on DMI or apparent nutrient digestibility. When supplemented in combination, no additive CH4 suppression was observed. FUM showed greater responses in increasing the molar proportion of propionate when supplemented with NPD than supplemented alone (by 10.2% vs. 4.4%). The rumen microbiota structure in the animals receiving FUM was different from that of the other animals, particularly changed the structure of phylum Firmicutes. Daily milk production and serum total antioxidant capacity were improved by NPD, but the contents of milk fat and protein were decreased, probably due to the bioactivity of absorbed NPD on body metabolism. CONCLUSIONS Supplementing NPD and FUM in combination is a promising way to persistently inhibit CH4 emissions with a higher rumen propionate proportion. However, the side effects of this nitrooxy compound on animals and its residues in animal products need further evaluation before it can be used as an animal feed additive.
Collapse
Affiliation(s)
- Zongjun Li
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Xinjian Lei
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Xiaoxu Chen
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Qingyan Yin
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Jing Shen
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Junhu Yao
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China.
| |
Collapse
|
4
|
Huang X, Yoder PS, Teixeira IAMA, Hanigan MD. Assessing amino acid uptake and metabolism in mammary glands of lactating dairy cows intravenously infused with methionine, lysine, and histidine or with leucine and isoleucine. J Dairy Sci 2021; 104:3032-3051. [PMID: 33455768 DOI: 10.3168/jds.2020-18169] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 10/06/2020] [Indexed: 12/29/2022]
Abstract
The objective of this study was to evaluate the effect of jugular infusions of 2 groups of AA on essential AA (EAA) transport and metabolism by mammary glands. Four Holstein cows in second lactation (66 ± 10 d in milk) were used in 4 × 4 Latin square design with a 2 × 2 factorial arrangement of treatments. Treatments were jugular infusions of saline; Met, Lys, and His (MKH); Ile and Leu (IL); or MKH plus IL (MKH+IL). Each period consisted of 8 d of no infusion followed by 8 d of jugular vein infusion of the treatment solutions. Amino acids were infused at rates of 21 g of Met, 38 g of Lys, 20 g of His, 50 g of Leu, and 22 g of Ile per day. Cows were fed a basal diet consisting of 15.2% crude protein with adequate rumen degradable protein but 15% deficient in MP based on estimates by Cornell Net Carbohydrate and Protein System (v6.5). On the last day of each period, 13C-AA derived from algae was infused into the jugular vein over 6 h, and blood and milk samples were collected before, during, and after infusion. Plasma and milk samples were analyzed for AA isotopic enrichment, and a mammary compartmental model was fitted to the data to derive bidirectional transport and metabolism rates for individual EAA. Influx of Leu increased with IL, whereas influx of other EAA was not different among treatments. Cellular efflux of Met and Lys to venous plasma represented 12 to 34% of influx, whereas cellular efflux of Phe and BCAA represented 29 to 59% of influx. Increased efflux/influx ratios of Ile and Leu with IL but not Met and Lys with MKH demonstrated that increased Ile and Leu influx was mostly returned to plasma resulting in no change in net uptake or efficiency. The isotope results showed that mammary net uptake of Lys and Ile increased during MKH infusion. Net uptake of Met increased with MKH but only in the absence of IL. Catabolism of Lys and Met only increased with MKH alone, resulting in decreased efficiency for milk protein, which demonstrated that Ile and Leu infusion can spare Lys and Met for milk protein synthesis. Total AA uptake to milk output was not different from 1, implying the catabolized Met and Lys contributed nitrogen to nonessential AA. Overall, EAA uptake and metabolism in mammary glands of dairy cows varied across individual EAA and responded differently to respective AA supplements. In addition, uptake, retention, and end use of AA by mammary tissue is variable and dependent on the mix of AA provided. This variability, depending on the mix of AA absorbed, will change the efficiency of utilization of individual AA at the mammary gland level and consequently the whole-body level. Thus, it is inaccurate to use a fixed, constant efficiency within and across AA to represent tissue activity.
Collapse
Affiliation(s)
- X Huang
- Department of Dairy Science, Virginia Tech, Blacksburg 24060
| | - P S Yoder
- Department of Dairy Science, Virginia Tech, Blacksburg 24060; Perdue AgriBusiness LLC, Salisbury, MD 21804
| | - I A M A Teixeira
- Universidade Estadual Paulista, Jaboticabal, SP 14884-900, Brazil
| | - M D Hanigan
- Department of Dairy Science, Virginia Tech, Blacksburg 24060.
| |
Collapse
|
5
|
Pszczolkowski VL, Arriola Apelo SI. The market for amino acids: understanding supply and demand of substrate for more efficient milk protein synthesis. J Anim Sci Biotechnol 2020; 11:108. [PMID: 33292704 PMCID: PMC7659053 DOI: 10.1186/s40104-020-00514-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 09/18/2020] [Indexed: 11/10/2022] Open
Abstract
For dairy production systems, nitrogen is an expensive nutrient and potentially harmful waste product. With three quarters of fed nitrogen ending up in the manure, significant research efforts have focused on understanding and mitigating lactating dairy cows’ nitrogen losses. Recent changes proposed to the Nutrient Requirement System for Dairy Cattle in the US include variable efficiencies of absorbed essential AA for milk protein production. This first separation from a purely substrate-based system, standing on the old limiting AA theory, recognizes the ability of the cow to alter the metabolism of AA. In this review we summarize a compelling amount of evidence suggesting that AA requirements for milk protein synthesis are based on a demand-driven system. Milk protein synthesis is governed at mammary level by a set of transduction pathways, including the mechanistic target of rapamycin complex 1 (mTORC1), the integrated stress response (ISR), and the unfolded protein response (UPR). In tight coordination, these pathways not only control the rate of milk protein synthesis, setting the demand for AA, but also manipulate cellular AA transport and even blood flow to the mammary glands, securing the supply of those needed nutrients. These transduction pathways, specifically mTORC1, sense specific AA, as well as other physiological signals, including insulin, the canonical indicator of energy status. Insulin plays a key role on mTORC1 signaling, controlling its activation, once AA have determined mTORC1 localization to the lysosomal membrane. Based on this molecular model, AA and insulin signals need to be tightly coordinated to maximize milk protein synthesis rate. The evidence in lactating dairy cows supports this model, in which insulin and glucogenic energy potentiate the effect of AA on milk protein synthesis. Incorporating the effect of specific signaling AA and the differential role of energy sources on utilization of absorbed AA for milk protein synthesis seems like the evident following step in nutrient requirement systems to further improve N efficiency in lactating dairy cow rations.
Collapse
Affiliation(s)
- Virginia L Pszczolkowski
- Department of Animal and Dairy Sciences, University of Wisconsin-Madison, Madison, WI, USA.,Endocrinology and Reproductive Physiology Graduate Training Program, University of Wisconsin-Madison, Madison, WI, USA
| | - Sebastian I Arriola Apelo
- Department of Animal and Dairy Sciences, University of Wisconsin-Madison, Madison, WI, USA. .,Endocrinology and Reproductive Physiology Graduate Training Program, University of Wisconsin-Madison, Madison, WI, USA.
| |
Collapse
|
6
|
Cai J, Zhao FQ, Liu JX, Wang DM. Local Mammary Glucose Supply Regulates Availability and Intracellular Metabolic Pathways of Glucose in the Mammary Gland of Lactating Dairy Goats Under Malnutrition of Energy. Front Physiol 2018; 9:1467. [PMID: 30405429 PMCID: PMC6206160 DOI: 10.3389/fphys.2018.01467] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 09/28/2018] [Indexed: 01/29/2023] Open
Abstract
As glucose is the regulator of both the milk yield and mammary oxidative status, glucose supply is considered to play important nutritional and physiological role on mammary gland (MG) metabolism. However, inconsistent results were observed from different infusion methods to evaluate the effect of glucose on MG glucose metabolism. Thus, precise method should be developed to learn how availability and intracellular metabolic pathways of glucose in the MG are altered by the direct mammary glucose supply. In addition, limited information is available on the role of mammary glucose supply in milk synthesis in lactating ruminants under an energy-deficient diet. Direct glucose supply to the MG was implemented in the current study through the external pudendal artery infusion under an energy-deficient diet. Six doses of glucose (0, 20, 40, 60, 80, and 100 g/d) were infused through the external pudendal arteries, which is the main artery to the MG, to six lactating goats fed with basal diet meeting 81% energy requirement in a 6 × 6 Latin square design. Milk and lactose yields were both quadratically increased with increased glucose infusion, whereas the milk yield changed inconsistently with the increased energy balance (EB), indicating local glucose supply, rather than EB, improved milk production. Glucose fluxes in the MG were significantly increased and correlated with mammary plasma flow. However, the ratio of lactose yield to glucose absorbed by the MG was significantly decreased. The increased glucose fluxes in the MG and changed glucose-related metabolites in milk indicated that the glucose availability and intracellular metabolic pathways was regulated by local mammary glucose. Acute glycolysis consumed the superfluous glucose and induced accumulation of oxygen radicals in the MG during over-supplied glucose conditions. The present study provided insight to optimal glucose supply to the MG during the lactation.
Collapse
Affiliation(s)
- Jie Cai
- Institute of Dairy Science, College of Animal Sciences, Zhejiang University, Hangzhou, China
- Ministry of Education Key Laboratory of Molecular Animal Nutrition, Zhejiang University, Hangzhou, China
| | - Feng-Qi Zhao
- Institute of Dairy Science, College of Animal Sciences, Zhejiang University, Hangzhou, China
- Department of Animal and Veterinary Sciences, University of Vermont, Burlington, VT, United States
| | - Jian-Xin Liu
- Institute of Dairy Science, College of Animal Sciences, Zhejiang University, Hangzhou, China
- Ministry of Education Key Laboratory of Molecular Animal Nutrition, Zhejiang University, Hangzhou, China
| | - Di-Ming Wang
- Institute of Dairy Science, College of Animal Sciences, Zhejiang University, Hangzhou, China
- Ministry of Education Key Laboratory of Molecular Animal Nutrition, Zhejiang University, Hangzhou, China
| |
Collapse
|
7
|
Curtis RV, Kim JJ, Doelman J, Cant JP. Maintenance of plasma branched-chain amino acid concentrations during glucose infusion directs essential amino acids to extra-mammary tissues in lactating dairy cows. J Dairy Sci 2018; 101:4542-4553. [DOI: 10.3168/jds.2017-13236] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 01/02/2018] [Indexed: 01/14/2023]
|
8
|
Cai J, Wang D, Liu J. Regulation of fluid flow through the mammary gland of dairy cows and its effect on milk production: a systematic review. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2018; 98:1261-1270. [PMID: 28758674 DOI: 10.1002/jsfa.8605] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Revised: 07/27/2017] [Accepted: 07/27/2017] [Indexed: 06/07/2023]
Abstract
Dairy milk consists of more than 85% water. Therefore, understanding the regulation of fluid absorption in the mammary gland is relevant to improving milk production. In recent decades, studies using different approaches, including blood flow, transmembrane fluid flow, tight junction, fluid flow of the paracellular pathway and functional mammary epithelial cell state, have been conducted aiming to investigate how mammary gland fluid absorption is regulated. However, the relationship between regulation mechanisms of fluid flow and milk production has not been studied systematically. The present review summarizes a series of key milk yield regulatory factors mediated by whole-mammary fluid flow, including milk, mammary blood flow, blood/tissue fluid-cell fluid flow and cell-alveolus fluid flow. Whole-mammary fluid flow regulates milk production by altering transporter activity, ion channels, local microcirculation-related factors, driving force of fluid transport (osmotic pressure or electrochemical gradient), cellular connection state and a cell volume sensitive mechanism. In addition, whole-mammary fluid flow plays important roles in milk synthesis and secretion. Knowledge gained from fluid flow-mediated regulatory mechanisms of the dairy mammary gland will lead to a fundamental understanding of lactation biology and will be beneficial for the improvement of dairy productivity. © 2017 Society of Chemical Industry.
Collapse
Affiliation(s)
- Jie Cai
- Institute of Dairy Science, College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Diming Wang
- Institute of Dairy Science, College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Jianxin Liu
- Institute of Dairy Science, College of Animal Sciences, Zhejiang University, Hangzhou, China
| |
Collapse
|