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1.
J Environ Manage ; 348: 119282, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-37852084

ABSTRACT

Within the context of promotion tournaments among local governments, the management of economic growth goals plays a crucial role in China's economic development. Despite China's rise as the second-largest economy globally, it has also emerged as the largest emitter of carbon emissions. Since the implementation of the 12th Five-Year Plan in 2011, the Chinese central government has made carbon intensity targets mandatory indicators for national economic development. This has prompted local governments to pursue low-carbon growth and adjust their economic growth targets (EGT) to comply with carbon intensity constraints. In this study, a sample of 282 prefecture-level cities in China is used to empirically examine the impact of carbon intensity constraints on total factor carbon emission efficiency (TCE) using the intensity difference-in-differences (DID) framework. The study also emphasizes the role of the transmission channel for economic growth pressure (EGP). The findings of the study reveal several key results. Firstly, the implementation of carbon intensity constraints leads to an average increase of 8.24% in total factor carbon emission efficiency (TCE), which is supported by robustness tests, parallel trend analysis, and placebo tests. Secondly, these constraints result in an average decrease of 0.1828 in local governments' economic growth targets (EGT) and a reduction of 0.1269 in economic growth pressure (EGP). Thirdly, cities with a higher proportion of secondary industry experience a more significant mitigation effect, although the promotion of provincial EGT hinders this effect. Fourthly, synergistic policies can effectively promote low-carbon development, and government expenditure on technology and marketization can facilitate a positive relationship between carbon intensity constraints and TCE. Lastly, the effects of carbon intensity constraints vary across the east, middle, and west regions, suggesting the presence of heterogeneity. The article proposes a shift in the assessment of lower governments by superior governments, from growth assessment to low-carbon growth assessment.


Subject(s)
Carbon , Economic Development , China , Cities , Government
2.
J Environ Manage ; 342: 118288, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37263037

ABSTRACT

Industrial land serves as the fundamental basis for urban economic development and significantly contributes to carbon emissions. Effective market mechanisms are crucial for reducing carbon emissions. As such, investigating the impact of market-oriented allocation of industrial land (MAIL) on carbon emissions and its pathways is of substantial practical importance for global low-carbon development. This study constructs a theoretical framework examining the influence of MAIL on carbon emissions, focusing on 285 Chinese cities from 2003 to 2020. The spatial econometric model is employed to analyze the impact of MAIL on carbon emissions. The results show that: first, from a national perspective, MAIL not only reduces carbon emissions within a region but also in neighboring regions. Higher MAIL leads to more effective carbon emission reductions, which are persistent and hysteresis in time. Path analysis demonstrates that MAIL reduces carbon emissions by promoting industrial upgrading and technological innovation. Second, there are differences in the timeliness of carbon emission reduction effects in cities of different scales and regions. For cities of different scales, the carbon reduction effect of MAIL is more stable in large and medium cities compared to megacities and small cities, but in the short term, MAIL will hinder the industrial upgrading of megacities and thus is not conducive to carbon reduction. For different regional cities, the carbon reduction effect of MAIL is more stable in other regions except northeast region, and in the short term, MAIL will inhibit technological innovation in northeast region, which is not conducive to carbon reduction. Consequently, it is essential not only to design a top-level reform plan for MAIL in China but also to establish differentiated reform policies for MAIL, tailored to the unique characteristics of cities with different scales and regions, to effectively reduce carbon emissions.


Subject(s)
Carbon , Economic Development , China , Cities , Models, Econometric , Carbon Dioxide
3.
J Tradit Chin Med ; 41(6): 853-861, 2021 12.
Article in English | MEDLINE | ID: mdl-34939381

ABSTRACT

OBJECTIVE: To investigate the efficacy of Biejia (Carapax Trionycis) and Ezhu (Rhizoma Curcumae Phaeocaulis) couplet medicine on epithelial-mesenchymal transition (EMT), invasion and migration of MDA-MB-231 triple negative breast cancer (TNBC) cells based on PI3K/Akt/mTOR signaling pathway. METHODS: MDA-MB-231 cells were treated with different medicated serum as Biejia-, Ezhu-, Biejia-Ezhu (BJ-, EZ-, BJ-EZ-) groups, intervened with no drug rat serum and paclitaxel with final concentration of 33 nM (IC50) as negative and positive control (NC and PC) groups. CCK-8 assay, scratch test, and Transwell assay were used to examine cell proliferation, invasion, and migration. The expression of E-cadherin, N-cadherin, Vimentin, MMP-2, MMP-9, PI3K, Akt, p-Akt, mTOR, and p-mTOR was determined by Western blot, and the mRNA expression of PI3K, Akt and mTOR was determined by real-time polymerase chain reaction. RESULTS: BJ-EZ group inhibited proliferation after 24, 48, and 72 h compared with the NC group (P < 0.05, < 0.01 or < 0.001) and reduced the invasion and migration of MDA-MB-231 cells (P < 0.01 or < 0.001). In addition, BJ-EZ group upregulated the expression of E-cadherin, downregulated the expression of N-cadherin, Vimentin, MMP-2, and MMP-9 (P < 0.05, P < 0.01 or P < 0.001), and inhibited the mRNA and protein expression of PI3K, Akt (p-Akt), mTOR (p-mTOR) (P < 0.05, < 0.01 or < 0.001). CONCLUSION: Biejia (Carapax Trionycis) and Ezhu (Rhizoma Curcumae Phaeocaulis) couplet medicine can inhibit the proliferation, invasion, migration and EMT of MDA-MB-231 cells through PI3K/Akt/mTOR signaling pathway, and the effect is better than that of Biejia (Carapax Trionycis) or Ezhu (Rhizoma Curcumae Phaeocaulis) alone.


Subject(s)
Phosphatidylinositol 3-Kinases , Triple Negative Breast Neoplasms , Animals , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation , Epithelial-Mesenchymal Transition , Humans , Phosphatidylinositol 3-Kinases/genetics , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , Rats , Signal Transduction , TOR Serine-Threonine Kinases/genetics , TOR Serine-Threonine Kinases/metabolism , Triple Negative Breast Neoplasms/drug therapy
6.
BMC Microbiol ; 21(1): 75, 2021 03 06.
Article in English | MEDLINE | ID: mdl-33676418

ABSTRACT

OBJECTIVE: The aim of this study is to evaluate the efficacy of the strain Paenibacillus polymyxa HX-140, isolated from the rhizosphere soil of rape, to control Fusarium wilt of cucumber seedlings caused by Fusarium oxysporum f. sp. cucumerinum. RESULTS: Strain HX-140 was able to produce protease, cellulase, ß-1,3-glucanase and antifungal volatile organic compounds. An in vitro dual culture test showed that strain HX-140 exhibited broad spectrum antifungal activity against soil-borne plant pathogenic fungi. Strain HX-140 also reduced the infection of Fusarium wilt of cucumber seedlings by 55.6% in a greenhouse pot experiment. A field plot experiment confirmed the biocontrol effects and further revealed that antifungal activity was positively correlated with inoculum size by the root-irrigation method. Here, inoculums at 106 107 and 108 cfu/mL of HX-140 bacterial suspension reduced the incidence of Fusarium wilt of cucumber seedling by 19.5, 41.1, and 50.9%, respectively. CONCLUSIONS: Taken together, our results suggest that P. polymyxa HX-140 has significant potential in the control of Fusarium wilt and possibly other fungal diseases of cucumber.


Subject(s)
Biological Control Agents , Cucumis sativus/microbiology , Fusarium/physiology , Microbial Interactions/physiology , Paenibacillus polymyxa/physiology , Plant Diseases/prevention & control , Brassica napus/microbiology , Plant Diseases/microbiology , Seedlings/microbiology , Soil Microbiology
7.
Zhongguo Gu Shang ; 33(9): 883-6, 2020 Sep 25.
Article in Chinese | MEDLINE | ID: mdl-32959580

ABSTRACT

OBJECTIVE: To observe the application of modified traction therapy in traumatic atlantoaxial subluxation in adults. METHODS: The clinical data of 31 patients with atlantoaxial subluxation treated from March 2018 to June 2019 were restropectively analyzed. There were 15 males and 16 females, aged from 18 to 68 years old with an average of 39 years old, including 10 cases of 18-40 years, 15 cases of 41-60 years, 6 cases of 51-68 years. The main manifestations of the patients were limited neck movement, pain, and atlantoaxial CT scan showed different degrees of atlantoaxial subluxation. Three dimensional multifunctional traction bed was used for traction for 2 min, relaxation for 10 s. The traction angle starts from the rearward extension of 5°-10° and weight from 3-6 kg. The weight increased by 1 kg every two days until the symptoms were improved. Traction time was 30 min twice a day and 10 days for a course of treatment. One course of treatment was performed in patients with 1-2 mm left and right equal width of atlantoaxial space, and two courses of treatment were performed in patients with 3-4 mm left and right equal width of atlantoaxial space, and the course of treatment could be increased to 3 months in especially patients with serious problems, such as 4 mm left and right equal width of atlantoaxial space and no improvement after conventional treatment. The criteria to evaluate the clinical effect was cure:no pain in the neck, normal range of neck movement, CT showed normal atlantoaxial space and odontoid process was in the middle, patients with normal neck movement were followed up 1 month after the end of treatment;improvement:neck pain was significantly improved and CT showed that the left and right atlantoaxial space was less than 1 mm in equal width. RESULTS: Among the 31 patients, 17 cases were cured by one course of treatment, 11 cases were cured by 2 courses of treatment, and 2 caseswere improved. CONCLUSION: The modified traction therapy has obvious effect on adult traumatic atlantoaxial subluxation, especially the subluxation of 3-4 mm equal width in left and right atlantoaxial space, and this method is safe and reliable with good efficacy and the patients without discomfort.


Subject(s)
Atlanto-Axial Joint , Joint Dislocations , Odontoid Process , Spinal Fusion , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Traction , Young Adult
8.
Ultrasound Med Biol ; 46(8): 2030-2043, 2020 08.
Article in English | MEDLINE | ID: mdl-32475714

ABSTRACT

Sono-photodynamic therapy (SPDT) activates the same photo-/sonosensitizer and exerts more marked antitumor effects than sonodynamic therapy or photodynamic therapy. We aimed to explore the utilization of curcumin (CUR)-loaded poly(L-lactide-co-glycolide) microbubble (MB)-mediated SPDT (CUR-PLGA-MB-SPDT) in HepG2 liver cancer cells. The cytotoxicity and intracellular accumulation of CUR were determined. We used 40 µM CUR as the photo-/sonosensitizer for 3 h. In a comparison of CUR-SDT or CUR-PDT, HepG2 cell viability decreased and apoptotic rate increased in CUR-SPDT. The CUR-PLGA MBs had round spheres with smooth surfaces and an average size of 3.7 µm. In CUR-PLGA MBs, drug entrapment efficiency and drug-loading capacity were 74.29 ± 2.60% and 17.14 ± 0.60%, respectively. CUR-loaded PLGA MBs (CUR-PLGA MBs) had good biocompatibility with normal L02 cells and were almost non-cytotoxic to HepG2 cells. Among CUR-SDT, CUR-PDT, CUR-SPDT or CUR-PLGA-MB-SDT, the cell CUR-PLGA-MB-SPDT had the lowest viability. Transmission electron microscopy revealed pyroptosis and apoptosis in the CUR-PLGA-MB-SPDT group; the potential mechanism was related to the mitochondrial membrane potential loss and increased production of intracellular reactive oxygen species. These findings suggested that CUR-PLGA-MB-SPDT may be a promising treatment for liver cancer.


Subject(s)
Antineoplastic Agents/administration & dosage , Curcumin/administration & dosage , Liver Neoplasms/drug therapy , Microbubbles/therapeutic use , Photochemotherapy/methods , Ultrasonic Therapy/methods , Antineoplastic Agents/therapeutic use , Curcumin/therapeutic use , Drug Delivery Systems , Hep G2 Cells/drug effects , Humans , Microscopy, Confocal , Polylactic Acid-Polyglycolic Acid Copolymer , Spectrometry, Fluorescence
9.
Anal Chem ; 91(24): 15784-15790, 2019 12 17.
Article in English | MEDLINE | ID: mdl-31726823

ABSTRACT

Here, we demonstrate a modular, reconfigurable, and self-sufficient convective heat exchanger for regulation of temperature in microfluidic systems. The heat exchanger consists of polymer tubes wrapped around a plastic pole and fully embedded in an elastomer block, which can be easily mounted onto the microfluidic structure. It is compatible with various microfluidic geometries and materials. Miniaturized, battery-powered piezoelectric pumps are utilized to drive the heat carrying liquid through the heat exchanger at desired flow rates and temperatures. Customized temperature profiles can be generated by changing the configuration of the heat exchanger with respect to the microfluidic structure. Tailored dynamic temperature profiles can be generated by changing the temperature of the heat carrying liquid in successive cycles. This feature is used to study the calcium signaling of endothelial cells under successive temperature cycles of 24 to 37 °C. The versatility, simplicity, and self-sufficiency of the heat exchanger makes it suitable for various microfluidic based cellular assays.

10.
Chirality ; 31(1): 11-20, 2019 01.
Article in English | MEDLINE | ID: mdl-30417573

ABSTRACT

Anisodamine (654-1), a well-known cholinergic antagonist, is marketed as synthetic anisodamine (mixture of four isomers, 654-2) in China. To preparative resolution and comparison of the bioactivities of the four isomers of synthetic anisodamine, current work explores an economic and effective separation method by using preparative high performance liquid chromatography (HPLC) and diastereomer crystallization. Their absolute configurations were established by single-crystal X-ray diffraction and circular dichroism method. The purities of each isomer were more than 95%. Among them, 654-2-A2 (6R, 2'S configuration) exhibited better effect on cabachol preconditioned small intestine tension more than 654-2 and other isomers. The direct separation method without using HPLC was tried as well, which was still on progress. This is the first report of the method for preparative separation of four isomers of synthetic anisodamine which could be used for large-scale production in industry.

11.
Anal Chem ; 91(3): 2498-2505, 2019 02 05.
Article in English | MEDLINE | ID: mdl-30592407

ABSTRACT

Here, we demonstrate a multilayered microfluidic system integrated with commercially available polymer tubes for controlling the temperature of the sample under various static and dynamic conditions. Highly controllable temperature profiles can be produced by modulating the flow rate or inlet temperature of the water passing through the tubes. Customised temperature gradients can be created across the length or width of a channel by mismatching the inlet temperature of the tubes. Temperature cycles can also be produced by repeatedly switching the tubes between hot and cold flasks. Proof-of-concept experiments demonstrate the utility of this system for studying the drug-induced calcium signaling of human monocytes under dynamic thermal conditions. The versatility and simplicity of our system provides opportunities for studying temperature-sensitive chemical, biochemical, and biological samples under various operating conditions.

12.
Biomicrofluidics ; 12(4): 044115, 2018 Jul.
Article in English | MEDLINE | ID: mdl-30174774

ABSTRACT

Here, we describe a novel method for fabrication of microfluidic structures in classroom environments. This method is based on replica moulding of pasta structures in polydimethylsiloxane. Placing pasta structures on a petroleum jelly base layer enables templating round-shaped structures with controllable cross-sectional profiles. The pasta structures can be easily deformed and combined to create more complex 3D microfluidic structures. Proof-of-concept experiments indicate the capability of this method for studying the mixing of neighbouring flows, generation of droplets, lateral migration of particles, as well as culturing, shear stress stimulation, and imaging of cells. Our "do-it-in-classroom" method bridges the gap between the classroom and the laboratory.

13.
Lab Chip ; 18(18): 2730-2740, 2018 09 11.
Article in English | MEDLINE | ID: mdl-30063234

ABSTRACT

Here, we demonstrate a self-sufficient, inexpensive and disposable pressure pump using commercially available latex balloons. The versatility of the pump is demonstrated against various microfluidic structures, liquid viscosities, and ambient temperatures. The flow rate of the pump can be controlled by varying the size and thickness of the balloon. Importantly, the soft structure of the balloon allows for almost instantaneous change of the flow rate upon manual squeezing of the balloon. This feature has been used for dynamically changing the flow ratio of parallel streams in a T-shaped channel or varying the size of droplets in a droplet generation system. The self-sufficiency, simplicity of fabrication and operation, along with the low-cost of the balloon pump facilitate the widespread application of microfluidic technologies for various research, education, and in situ monitoring purposes.

14.
Int J Mol Med ; 42(2): 1018-1025, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29717773

ABSTRACT

Cucurbitacin B (CuB), the active component of a traditional Chinese herbal medicine, Pedicellus Melo, has been shown to exhibit antitumor and anti-inflammation effects, but its role in tumor angiogenesis, the key step involved in tumor growth and metastasis, and the involved molecular mechanism are unknown. Tumor angiogenesis is one of the hallmarks of the development in malignant neoplasias and metastasis. Effective targeting of tumor angiogenesis is a key area of interest for cancer therapy. Here, we demonstrated that CuB significantly inhibited human umbilical vascular endothelial cell (HUVEC) proliferation, migration, tubulogenesis in vitro, and blocked angiogenesis in chick embryo chorioallantoic membrane (CAM) assay in vivo. Furthermore, CuB induced HUVEC apoptosis and may induce apoptosis by triggering the mitochondrial apoptotic pathway. Finally, we found that CuB inhibiting angiogenesis was associated with inhibition of the activity of vascular endothelial growth factor receptor 2 (VEGFR2). Our investigations suggested that CuB was a potential drug candidate for angiogenesis related diseases.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Endothelial Cells/drug effects , Mitochondria/drug effects , Neoplasms/blood supply , Neovascularization, Pathologic/drug therapy , Signal Transduction/drug effects , Triterpenes/pharmacology , Animals , Chick Embryo , Endothelial Cells/metabolism , Hep G2 Cells , Human Umbilical Vein Endothelial Cells , Humans , Mitochondria/metabolism , Neoplasms/drug therapy , Neoplasms/metabolism , Neovascularization, Pathologic/metabolism , Vascular Endothelial Growth Factor A/metabolism
15.
Fish Shellfish Immunol ; 77: 31-39, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29551666

ABSTRACT

The COMMD (COpper Metabolism gene MURR1 Domain) gene family with ten members participates in various biological processes, such as the regulation of copper and sodium transport, NF-κB activity and cell cycle progression. However, studies on the COMMD gene family in amphioxus (Branchiostoma belcheri) are yet largely unknown. In this study, we have identified and characterized the ten COMMD family members from amphioxus (designated as AmphiCOMMDs). Firstly, we clone the full length of AmphiCOMMDs, and all AmphiCOMMD proteins contain the conserved COMM domain with two NES (Nuclear Export Signal) motifs. Secondly, the genomic structure analysis demonstrates that genes of the COMMD family have undergone intron loss and gain during the process of divergence from amphioxus to vertebrates. Thirdly, phylogenetic analysis indicates that AmphiCOMMDs are more closely related to vertebrates, implying the AmphiCOMMDs may be the ancestor of the vertebrate COMMDs. Fourthly, AmphiCOMMDs are ubiquitously and differentially expressed in five investigated tissues (muscles, gills, intestine, heaptic cecum and notochord). Finally, our results show that expression levels of AmphiCOMMD genes are fluctuating after LPS stimulation to some different extent. Taken together, our studies have elaborated the evolutionary dynamic and the innate immune role of the COMMD family genes in amphioxus.


Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/immunology , Evolution, Molecular , Gene Expression Regulation/immunology , Immunity, Innate/genetics , Lancelets/genetics , Lancelets/immunology , Adaptor Proteins, Signal Transducing/metabolism , Amino Acid Sequence , Animals , Gene Expression Profiling , Lancelets/metabolism , Multigene Family/genetics , Phylogeny , Sequence Alignment
16.
J Cell Biochem ; 119(1): 659-668, 2018 01.
Article in English | MEDLINE | ID: mdl-28636115

ABSTRACT

This study explored the effects involved in silencing CLIC4 on apoptosis and proliferation of mouse liver cancer Hca-F and Hca-P cells. A CLIC4-target small interfering RNA (siRNA) was designed to compound into two individual complementary oligonucleotide chains. A process of annealing and connection to a pSilencer vector was followed by transfection with Hca-F and Hca-P cells. Quantitative real-time polymerase chain reaction and Western blotting techniques were used to determine CLIC4 mRNA and protein expressions. CCK8 assay and flow cytometry were employed for analysis of the survival and apoptosis rate as well as the cell cycle in an octreotide-induced apoptosis model. Expressions of caspase 3, caspase 9, and cleaved PARP were measured using Western blotting. The CLIC4 mRNA and protein expressions in Hca-F and Hca-P cells transfected by pSilencer-CLIC4 siRNA plasmid in the blank group displayed remarkably decreased levels of expression, when compared with both the control and negative control (NC) groups. Decreased survival rates and cleaved PARP expression, increased cell apoptosis rate,expressions of caspase 3 and caspase 9 in Hca-F and Hca-P cells were detected in groups that had been cultured in a medium containing octreotide. The pSilencer-CLIC4 siRNA-2 group when compared with the control and NC groups exhibited decreased survival rates, cleaved PARP expression, increased cell apoptosis rates, and increased expressions of caspase 3 and caspase 9 of Hca-F and Hca-P cells. The results demonstrated that siRNA-induced down-regulation of CLIC4 could proliferation, while in turn promoting apoptosis of mouse liver cancer Hca-F and Hca-P cells. J. Cell. Biochem. 119: 659-668, 2018. © 2017 Wiley Periodicals, Inc.


Subject(s)
Chloride Channels/genetics , Chloride Channels/metabolism , Gene Knockdown Techniques , Liver Neoplasms/genetics , Liver Neoplasms/veterinary , Mitochondrial Proteins/genetics , Mitochondrial Proteins/metabolism , Animals , Apoptosis , Caspase 3/genetics , Caspase 3/pharmacology , Caspase 9/genetics , Caspase 9/pharmacology , Cell Line, Tumor , Cell Proliferation , Gene Expression Regulation, Neoplastic/drug effects , Liver Neoplasms/metabolism , Mice , Octreotide/pharmacology , Poly(ADP-ribose) Polymerases/metabolism , RNA, Small Interfering/genetics
17.
Lab Chip ; 17(22): 3862-3873, 2017 11 07.
Article in English | MEDLINE | ID: mdl-29034403

ABSTRACT

Generating customised temperature gradients in miniaturised flow-free liquid chambers is challenging due to the dominance of diffusion. Inducing internal flows in the form of vortices is an effective strategy for overcoming the limitations of diffusion in such environments. Vortices can be produced by applying pressure, temperature and electric potential gradients via miniaturised actuators. However, the difficulties associated with the fabrication, integration, maintenance and operation of such actuators hinder their utility. Here, we utilise liquid metal enabled pumps to induce vortices inside a miniaturised liquid chamber. The configuration and rotational velocity of these vortices can be controlled by tuning the polarity and frequency of the energising electrical signal. This allows creation of customised spatial temperature gradients inside the chamber. The absence of conventional moving elements in the pumps facilitates the rapid reconfiguration of vortices. This enables quick transition from one temperature profile to another, and creates customised spatiotemporal temperature gradients. This allows temperature oscillation from 35 to 62 °C at the hot spot, and from 25 to 27 °C at the centre of the vortex within 15 seconds. Our liquid metal enabled vortex generator can be fabricated, integrated and operated easily, and offers opportunities for studying thermo-responsive materials and biological samples.

18.
Sci Rep ; 7(1): 5945, 2017 07 19.
Article in English | MEDLINE | ID: mdl-28724996

ABSTRACT

The laminar nature of microfluidic flows is most elegantly demonstrated via the confluence of two fluids forming two stable parallel flows within a single channel meeting at a highly stable interface. However, maintenance of laminar conditions can become complicated when there is a large viscosity contrast between the neighbouring flows leading to unique instability patterns along their interface. Here, we study the dynamics of high viscosity contrast confluent flows - specifically a core flow made of highly viscous glycerol confined by sheath flows made of water within a microfluidic flow focusing system. Our experiments indicate the formation of tapered core structures along the middle of the channel. Increasing the sheath flow rate shortens the tapered core, and importantly induces local instability patterns along the interface of core-sheath flows. The dynamics of such tapered core structures is governed by the intensity of instability patterns and the length of the core, according to which the core structure can experience stable, disturbed, broken or oscillated regimes. We have studied the dynamics of tapered core structures under these regimes. In particular, we have analysed the amplitude and frequency of core displacements during the broken core and oscillating core regimes, which have not been investigated before.

19.
Lab Chip ; 17(6): 974-993, 2017 03 14.
Article in English | MEDLINE | ID: mdl-28225135

ABSTRACT

Several gallium-based liquid metal alloys are liquid at room temperature. As 'liquid', such alloys have a low viscosity and a high surface tension while as 'metal', they have high thermal and electrical conductivities, similar to mercury. However, unlike mercury, these liquid metal alloys have low toxicity and a negligible vapor pressure, rendering them much safer. In comparison to mercury, the distinguishing feature of these alloys is the rapid formation of a self-limiting atomically thin layer of gallium oxide over their surface when exposed to oxygen. This oxide layer changes many physical and chemical properties of gallium alloys, including their interfacial and rheological properties, which can be employed and modulated for various applications in microfluidics. Injecting liquid metal into microfluidic structures has been extensively used to pattern and encapsulate highly deformable and reconfigurable electronic devices including electrodes, sensors, antennas, and interconnects. Likewise, the unique features of liquid metals have been employed for fabricating miniaturized microfluidic components including pumps, valves, heaters, and electrodes. In this review, we discuss liquid metal enabled microfluidic components, and highlight their desirable attributes including simple fabrication, facile integration, stretchability, reconfigurability, and low power consumption, with promising applications for highly integrated microfluidic systems.

20.
Sci Rep ; 6: 29582, 2016 07 08.
Article in English | MEDLINE | ID: mdl-27387420

ABSTRACT

Fibroblast growth factor-21 (FGF21) is closely related to various metabolic and cardiovascular disorders. However, the direct targets and mechanisms linking FGF21 to blood pressure control and hypertension are still elusive. Here we demonstrated a novel regulatory function of FGF21 in the baroreflex afferent pathway (the nucleus tractus solitarii, NTS; nodose ganglion, NG). As the critical co-receptor of FGF21, ß-klotho (klb) significantly expressed on the NTS and NG. Furthermore, we evaluated the beneficial effects of chronic intraperitoneal infusion of recombinant human FGF21 (rhFGF21) on the dysregulated systolic blood pressure, cardiac parameters, baroreflex sensitivity (BRS) and hyperinsulinemia in the high fructose-drinking (HFD) rats. The BRS up-regulation is associated with Akt-eNOS-NO signaling activation in the NTS and NG induced by acute intravenous rhFGF21 administration in HFD and control rats. Moreover, the expressions of FGF21 receptors were aberrantly down-regulated in HFD rats. In addition, the up-regulated peroxisome proliferator-activated receptor-γ and -α (PPAR-γ/-α) in the NTS and NG in HFD rats were markedly reversed by chronic rhFGF21 infusion. Our study extends the work of the FGF21 actions on the neurocontrol of blood pressure regulations through baroreflex afferent pathway in HFD rats.


Subject(s)
Fibroblast Growth Factors/metabolism , Fructose/adverse effects , Hyperinsulinism/drug therapy , Hypertension/drug therapy , Recombinant Proteins/administration & dosage , Animals , Baroreflex/drug effects , Blood Pressure/drug effects , Disease Models, Animal , Humans , Hyperinsulinism/chemically induced , Hyperinsulinism/metabolism , Hypertension/chemically induced , Hypertension/metabolism , Infusions, Parenteral , Male , Nodose Ganglion/drug effects , Nodose Ganglion/metabolism , Rats , Receptors, Fibroblast Growth Factor/metabolism , Recombinant Proteins/pharmacology , Signal Transduction/drug effects , Solitary Nucleus/drug effects , Solitary Nucleus/metabolism
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