4,295 research outputs found
Expression and significance of HIF-1 α and VEGF in rats with diabetic retinopathy
AbstractObjectiveTo investigate the expression of hypoxia inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) in diabetic retinopathy (DR) rats and its effect on the DR occurrence and development.MethodsA total of 120 SD rats were randomly divided into trial group and control group with 60 in each. STZ i.p. was used in the trial group to establish the DM model, citrate buffer salt of same amount was used i.p. to the control group. 1, 3 and 6 months after injection, respective 20 rats were sacrificed in each group to observe expression of HIF-1α and VEGF in the rat retina tissue at different time points.ResultsExpression of HIF-1α and VEGF were negative in the control group; expression of HIF-1α and VEGF protein in retinal tissue were weak after 1 month of DR mold formation. It showed progressive enhancement along with the progression in different organizations, differences between groups were significant (P<0.05).ConclusionsExpressions of HIF-1α and VEGF were correlated with disease progression in early diabetic retinopathy. Retinal oxygen can induce over-expression of HIF-1α and VEGF. It shows that HIF-1α and VEGF play an important role in the pathogenesis of DR
High-Order Leader-Follower Tracking Control under Limited Information Availability
Limited information availability represents a fundamental challenge for
control of multi-agent systems, since an agent often lacks sensing capabilities
to measure certain states of its own and can exchange data only with its
neighbors. The challenge becomes even greater when agents are governed by
high-order dynamics. The present work is motivated to conduct control design
for linear and nonlinear high-order leader-follower multi-agent systems in a
context where only the first state of an agent is measured. To address this
open challenge, we develop novel distributed observers to enable followers to
reconstruct unmeasured or unknown quantities about themselves and the leader
and on such a basis, build observer-based tracking control approaches. We
analyze the convergence properties of the proposed approaches and validate
their performance through simulation
Holographic conductivity from Einstein-Maxwell-Dilaton in Gauss-Bonnet gravity and Entropy Function
In this paper we consider the holographic DC and Hall conductivity in
Einstein-Maxwell-Dilaton in Gauss-Bonnet gravity with momentum dissipation. We
analytically derived the DC conductivity and Hall conductivity from the black
horizon data, and found that the conductivities are independent on the
Gauss-Bonnet coupling. We also used the entropy function formalism to get the
conductivities in terms of the charge of the black hole, even without knowing
the explicit black hole solutions.Comment: 15 page
A New Method to Calculate Electromagnetic Impedance Matching Degree in One-Layer Microwave Absorbers
A delta-function method was proposed to quantitatively evaluate the
electromagnetic impedance matching degree. Measured electromagnetic parameters
of {\alpha}-Fe/Fe3B/Y2O3 nanocomposites are applied to calculate the matching
degree by the method. Compared with reflection loss and quarter-wave principle
theory, the method accurately reveals the intrinsic mechanism of microwave
transmission and reflection properties. A possible honeycomb structure with
promising high-performance microwave absorption according to the method is also
proposed.Comment: 13 pages, 3 figure
Short communication: Melatonin implantation during the non-growing period of cashmere increases the cashmere yield of female Inner Mongolian cashmere goats by increasing fiber length and density
This study aimed to evaluate if melatonin implantation at the end of April and June was able to increase cashmere production in female Inner Mongolian cashmere goats and to search for contributing factors accounting for the melatonin increasing in cashmere production. One hundred and fifty female Inner Mongolian cashmere goats (initial body weight 37.2 ± 3.3 kg) were randomly assigned to either a control (n=75) or a treatment (n=75) group. Goats in the treatment group were implanted with melatonin (2 mg/kg of body weight) on April 30 and June 30, 2014 while goats in the control received no treatment. Melatonin implantation increased cashmere yield by 23.4% while increasing the length and density of the cashmere fiber by 19.8% and 11.4%, whereas it decreased cashmere fiber diameter by 4.4%. Melatonin treatment had no effect on doe growth, litter size or birth and weaning weights of kid. Melatonin implantation promoted cashmere yield by increasing fiber length and density without impacting the performance of goats and their offspring. Therefore, melatonin implantation during the cashmere non-growing period (late April and June) is an effective way to increase cashmere yield and improve cashmere characteristics of goats
One-stitch anastomosis through the skin with bicanalicular intubation:a modified approach for repair of bicanalicular laceration
<b>AIM:</b> To evaluate the efficacy and safety of one-stitch anastomosis through the skin with bicanalicular silicone tube intubation in repairing of bicanalicular laceration.<b>METHODS:</b>The clinical data of 15 consecutive patients with both superior and inferior canalicular laceration in one eye who underwent surgical repair using one-stitch anastomosis through the skin and bicanalicular stent were retrospective studied. All the operations were performed under surgical microscope, 5-0 silk sutures were used and were with bicanalicular silicone tube (diameter was 8mm) intubation, for one lacerated canaliculi one-stitch anastomosis through the skin. The stents were left in place for 3 months postoperatively and then removed. The follow-up period was 3 - 36 months (average 14 months).<b>RESULTS:</b>In 15 patients, 13 patients were cured entirely, 1 patient was meliorated, 1 patient with no effects. All patients had got good recovery of eyelid laceration with no traumatic deformity in eyelid and canthus. Complication was seen in one case, for not followed the doctor’s guidance to come back to hospital to had the suture removed on the 7<sup>th</sup> day after operation, when he came at the 15<sup>th</sup> day, the inferior canalicular wall and eyelid skin were corroded by the suture caused 2mm wound, and the inside silicone tube was exposed, a promptly repair with 10-0 nylon suture was done, the wound healed in a week. There were no early tube protrusions and punctal slits in the patients.<b>CONCLUSION:</b>One-stitch anastomosis through the skin with bicanalicular silicone tube intubation is a good method in repair of bicanalicular laceration in one eye, the cut ends can be anastomosed directly, and with excellent cosmetic results, it is acceptable for the patients. For there is no suture remained in the wound permanently, so there is no suture-related granuloma which may cause obstruction or stenosis of canaliculi. It is simple, economical, effective and safe
Mitochondrial EF4 links respiratory dysfunction and cytoplasmic translation in Caenorhabditis elegans
AbstractHow animals coordinate cellular bioenergetics in response to stress conditions is an essential question related to aging, obesity and cancer. Elongation factor 4 (EF4/LEPA) is a highly conserved protein that promotes protein synthesis under stress conditions, whereas its function in metazoans remains unknown. Here, we show that, in Caenorhabditis elegans, the mitochondria-localized CeEF4 (referred to as mtEF4) affects mitochondrial functions, especially at low temperature (15°C). At worms' optimum growing temperature (20°C), mtef4 deletion leads to self-brood size reduction, growth delay and mitochondrial dysfunction. Transcriptomic analyses show that mtef4 deletion induces retrograde pathways, including mitochondrial biogenesis and cytoplasmic translation reorganization. At low temperature (15°C), mtef4 deletion reduces mitochondrial translation and disrupts the assembly of respiratory chain supercomplexes containing complex IV. These observations are indicative of the important roles of mtEF4 in mitochondrial functions and adaptation to stressful conditions
CRP-Induced NLRP3 Inflammasome Activation Increases LDL Transcytosis Across Endothelial Cells
The NLRP3 inflammasome, a multiprotein cytosolic complex that activates the IL-1 family of cytokines, plays an important role in atherosclerosis (AS). High-sensitivity c-reactive protein (hs-CRP) is widely recognized as a major cardiovascular risk predictor and recent studies name NLRP3 as a predictor of CRP levels. Mounting evidence has indicated that subendothelial retention of apolipoprotein B100-containing lipoproteins, such as low-density lipoprotein (LDL), is the initial step of atherogenesis, and is usually termed the “response to retention hypothesis.” We previously reported that CRP promotes AS by directly increasing LDL transcytosis across endothelial cells (ECs). The present study aims to investigate the effects of CRP on NLRP3 inflammasome activation and the role of the NLRP3 inflammasome in CRP-induced LDL transcytosis. We found that CRP upregulated NF-κB activity, the NF-κB inhibitor (BAY-11-7082) and Fcγ receptors (FcγRs) inhibitor (CD32/64Ab) blocked CRP-induced NF-κB activation. CRP also induced expression of pro-IL-1β and NLRP3, while BAY and CD32/64 Ab suppressed CRP-mediated expression of NLRP3 and pro-IL-1β. Moreover, CRP activated the NLRP3 inflammasome in ECs. NADPH oxidase inhibitor, diphenylene iodonium (DPI) and dithiothreitol (DTT), a broad-spectrum P2 receptor inhibitor, oxidized ATP (oATP), and a broad inhibitor of cysteine proteases, E-64d, inhibited CRP-induced NLRP3 inflammasome activation. Furthermore, NLRP3 siRNA and caspase-1 inhibitor blocked CRP-mediated LDL transcytosis across ECs. In conclusion, NLRP3 inflammasome activation was shown to be involved in CRP-mediated LDL transcytosis across ECs. CRP not only increased the expression of pro-IL-1β and NLRP3 via the FcγRs/NF-κB pathway, but also promoted NLRP3 inflammasome activation and IL-1β maturation by upregulation of reactive oxygen species (ROS) levels, purinergic receptor signaling, and activation of cysteine proteases
Efficient Generalization Improvement Guided by Random Weight Perturbation
To fully uncover the great potential of deep neural networks (DNNs), various
learning algorithms have been developed to improve the model's generalization
ability. Recently, sharpness-aware minimization (SAM) establishes a generic
scheme for generalization improvements by minimizing the sharpness measure
within a small neighborhood and achieves state-of-the-art performance. However,
SAM requires two consecutive gradient evaluations for solving the min-max
problem and inevitably doubles the training time. In this paper, we resort to
filter-wise random weight perturbations (RWP) to decouple the nested gradients
in SAM. Different from the small adversarial perturbations in SAM, RWP is
softer and allows a much larger magnitude of perturbations. Specifically, we
jointly optimize the loss function with random perturbations and the original
loss function: the former guides the network towards a wider flat region while
the latter helps recover the necessary local information. These two loss terms
are complementary to each other and mutually independent. Hence, the
corresponding gradients can be efficiently computed in parallel, enabling
nearly the same training speed as regular training. As a result, we achieve
very competitive performance on CIFAR and remarkably better performance on
ImageNet (e.g. ) compared with SAM, but always require half
of the training time. The code is released at https://github.com/nblt/RWP
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