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Unintended end-of-process depression (EOPD) commonly occurs in laser powder bed fusion (LPBF), leading to poor surface quality and lower fatigue strength, especially for many implants. In this study, a high-fidelity multi-physics meso-scale simulation model is developed to uncover the forming mechanism of this defect. A defect-process map of the EOPD phenomenon is obtained using this simulation model. It is found that the EOPD formation mechanisms are different under distinct regions of process parameters. At low scanning speeds in keyhole mode, the long-lasting recoil pressure and the large temperature gradient easily induce EOPD. While at high scanning speeds in keyhole mode, the shallow molten pool morphology and the large solidification rate allow the keyhole to evolve into an EOPD quickly. Nevertheless, in the conduction mode, the Marangoni effects along with a faster solidification rate induce EOPD. Finally, a 'step' variable power strategy is proposed to optimise the EOPD defects for the case with high volumetric energy density at low scanning speeds. This work provides a profound understanding and valuable insights into the quality control of LPBF fabrication. [ABSTRACT FROM AUTHOR]

Hybrid rocket engines suffer from the restricted mechanical properties and low regression rates of current polymeric fuel grains. We propose a three-dimensional printed aluminium (Al) nested composite fuel grain with millimetre-scale lattice pores (referred to as Al-L). In this study, breathable Al blades with micrometer-scale interconnected pores (Al-B) and blades combining millimetre-scale and micrometer-scale pores (Al-B&L) are designed. The formation mechanisms, characteristics, and effects of the breathable blades are analysed in simulations, microcomputed tomography, and cyclic compression tests. The mechanical properties of the composite fuel grains are investigated numerically and in compression tests. Al-B has the highest Young's modulus at more than 15 times that of a paraffin-based fuel grain and Al-B&L has the highest yield stress at 4 times that of the paraffin-based fuel grain. Referring to combustion properties, the regression rates of the Al-B and Al-B&L grains are respectively 63.3% and 58.2% greater than the regression rate of the paraffin-based fuel grain. [ABSTRACT FROM AUTHOR]

Residual stresses, related distortions and cracks are detrimental in metallic Additive Manufacturing (AM). Previously developed stress-control strategies based on reducing thermal gradients hardly diminish the stress concentrations at the built basement and easily affect other physical phenomena involved in AM. To overcome this, a novel strategy, named as Smart-Substrate, consisting of optimising the inner structure and local stiffness of the substrate is proposed to avert stress accretion and related part deformations. To demonstrate its advantages, a coupled thermomechanical finite element model for AM, experimentally calibrated with in-situ temperature and displacement measurements, is employed to analyse the thermal and mechanical behaviour of three groups of different structures with increasing geometrical complexity (single-wall, rectangular and block parts) fabricated by Directed Energy Deposit (DED) on the standard and smart substrates, respectively. Through using Smart-Substrate, the generation of residual stresses, especially the stress concentrations at the bottom corner of DED-builds being highly sensitive to cracks, and the induced deflections, are fundamentally throttled, and contrariwise for the standard substrate. More importantly, the use of Smart- Substrate is almost without prejudice to the temperature field, metallurgy and resulting mechanical hardness. This provides a possibility for addressing different physical problems individually, enlarging the AM process window. [ABSTRACT FROM AUTHOR]

Once fires occur in a coalfield, large quantities of coal in the coalfield will be baked at high temperatures. The changes and differences in the microscopic and spontaneous combustion properties of coals in high-temperature environments (ambient temperature or even after high-temperature baking) in the fire zone have not been studied yet. In this paper, three types of different-rank coals were baked at five different temperatures to investigate their changes in microcrystalline compositions, functional groups and combustion characteristics. The following results were obtained. The temperature treatment causes damage to the microcrystalline structure of different-rank coals. As the baking temperature rises, the aromatic layer spacing decreases, while the ductility and stacking height gradually increase. The aromatic ether content and the aliphatic hydrocarbon content gradually decline, while the -COOH content goes first and then falls. The spontaneous combustion activities of coals around the fire area gradually weaken with the rise of baking temperature. This research is crucial for revealing the effect of temperature, especially fire baking, on the spontaneous combustion characteristics of coal. [ABSTRACT FROM AUTHOR]

Objective: Bi-level positive airway pressure (BiPAP) and synchronized intermittent mandatory ventilation (SIMV) can be used to achieve peak inspiratory pressure and positive end-expiratory pressure to avoid alveolar collapse and improve oxygenation in preterm infants during the treatment of respiratory distress syndrome (RDS), and there is an urgent demand for evaluating the effects and prognoses of these two ventilation modes. Study design: We conducted a retrospective study on preterm infants (≤32 weeks and <2500 g) from March 2015 to March 2020 with BiPAP (n = 63) and SIMV (n = 63). The primary outcomes were successful treatment and weaning within 72 h, the demand for a second pulmonary surfactant supply and the need for a second respiratory support. The secondary outcome was the incidence of complications. Results: There were no significant differences (p > .05) in the primary outcomes or the incidence of complications (pneumonia, apnea, respiratory failure, air leak syndrome, persistence of patent ductus arteriosus, neonatal sepsis, necrotizing enterocolitis, retinopathy of prematurity, and intraventricular hemorrhage). There were significant differences (p < .05) in the incidence of pulmonary hemorrhage, bronchopulmonary dysplasia and IVH (grade II). Conclusions: Although both BiPAP and SIMV achieved good early treatment outcomes of RDS in preterm infants, BiPAP support is recommended for reducing the incidence of pulmonary hemorrhage, bronchopulmonary dysplasia and IVH (grade II) if infants are tolerant. Attempts should be made to prevent these complications from happening with the use of SIMV support if infants are intolerant. [ABSTRACT FROM AUTHOR]

Context: Danggui Niantong Granules (DGNTG) are a valid and reliable traditional herbal formula, commonly used in clinical practice to treat rheumatoid arthritis (RA). However, the mechanism of its effect on RA remains unclear. Objective: An investigation of the therapeutic effects of DGNTG on RA. Materials and methods: Twenty-four male Sprague-Dawley (SD) rats were divided into four groups: control, model, DGNTG (2.16 g/kg, gavage), methotrexate (MTX) (1.35 mg/kg, gavage) for 28 days. The morphology of synovial and ankle tissues was observed by haematoxylin-eosin staining. The responses of mitochondrial apoptosis were assessed by qPCR, Western blotting and immunohistochemical staining. Rat faeces were analysed by 16S rRNA sequencing. Results: Our results showed that DGNTG treatment reduced AI scores (7.83 ± 0.37 vs. 4.67 ± 0.47, p<0.01) and paw volumes (7.63 ± 0.17 vs. 6.13 ± 0.11, p<0.01) compared with the model group. DGNTG also increased the expression of Bax (0.34 ± 0.03 vs. 0.73 ± 0.03, p<0.01), cytochrome c (CYTC) (0.24 ± 0.02 vs. 0.64 ± 0.01, p<0.01) and cleaved caspase-9 (0.24 ± 0.04 vs. 0.83 ± 0.08, p<0.01), and decreased bcl-2 (1.70 ± 0.11 vs. 0.60 ± 0.09, p<0.01) expression. DGNTG treatment regulated the structure of gut microbiota. Discussion and conclusions: DGNTG ameliorated RA by promoting mitochondrial apoptosis, which may be associated with regulating gut microbiota structure. DGNTG can be used as a supplement and alternative drug for the treatment of RA; its ability to prevent RA deserves further study. [ABSTRACT FROM AUTHOR]

A new microstructure-dependent non-classical model for Kirchhoff plates is developed by using a reformulated strain gradient elasticity theory that incorporates both the strain gradient and couple stress effects. The equation of motion and the boundary conditions are simultaneously obtained through a variational formulation based on Hamilton's principle. The new plate model contains one material constant to account for the strain gradient effect and one material length scale parameter to capture the couple stress effect. The newly developed non-classical plate model includes the plate model incorporating the couple stress effect alone and the plate model based on the classical elasticity as two special cases. To illustrate the new model, the buckling, static bending and free vibration problems of a simply supported rectangular plate are analytically solved by directly applying the general formulas derived. The numerical results reveal that the presence of the strain gradient and couple stress effects leads to reduced plate deflections, enlarged critical buckling loads and increased natural frequencies. These microstructure effects are significant when the plate is very thin, but they are diminishing as the plate thickness increases. These predicted trends of the size effects at the micron scale agree with those observed experimentally. [ABSTRACT FROM AUTHOR]

In order to better explore the spontaneous combustion characteristics of lignite, a low-temperature heating experimental device was used to study the changes in the physical and chemical structure of lignite in an air atmosphere of 50–350°C. Through FTIR, XRD and SEM, the coal sample's chemical structure and surface microstructure change at low temperature are correlated and analysed, and the physical and chemical fabric change law of the coal sample at low temperature is obtained. The results show that in the water loss stage, the hydroxyl content in the coal sample increases, and the surface pores of the coal sample become larger. As the oxidation temperature increases, the pores further expand, secondary cracks appear, and gas escapes. In the decarboxylation stage, the coal sample is further coked, the methyl group increases, the oxygen-containing functional group increases, and the coal sample crystallisation degree increases, which accelerates the spontaneous combustion of the coal sample. The result of our study offers useful guide for early coal spontaneous combustion prediction on site. [ABSTRACT FROM AUTHOR]

Objective: Low triiodothyronine syndrome (LT3S) is a common endocrine disease in preterm neonates. Various serious acute or chronic diseases result in LT3S. Few studies have investigated the causal relationship between perinatal factors and LT3S in preterm neonates with a gestational age (GA) of 28-35 weeks. The present study comprehensively analyzed the perinatal factors of LT3S in preterm neonates. Methods: This was a retrospective study of neonates with and without LT3S from January 2018 to November 2019. Compared to 206 preterm neonates without LT3S, 158 neonates were diagnosed with LT3S, excluding neonates with congenital malformations, other endocrine diseases, genetic diseases and inherited metabolic diseases. Results: Five perinatal risk factors for LT3S were confirmed using univariate and multivariate analyses: smaller gestational age, lower birth weight, respiratory distress syndrome (RDS), neonatal sepsis, and dopamine use. Conclusions: LT3S in preterm neonates was associated with multiple perinatal factors, including smaller gestational age, lower birth weight, RDS, sepsis, and dopamine use. Preterm neonates with a GA of 28-35 weeks who are exposed to a series of high-risk perinatal factors must be closely observed, diagnosed early and treated for primary diseases promptly to reduce the occurrence of LT3S and improve the outcomes. [ABSTRACT FROM AUTHOR]

Huashi Baidu formula (HSBDF) was developed to treat the patients with severe COVID-19 in China. The purpose of this study was to explore its active compounds and demonstrate its mechanisms against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) through network pharmacology and molecular docking. All the components of HSBDF were retrieved from the pharmacology database of TCM system. The genes corresponding to the targets were retrieved using UniProt and GeneCards database. The herb–compound–target network was constructed by Cytoscape. The target protein–protein interaction network was built using STRING database. The core targets of HSBDF were analyzed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). The main active compounds of HSBDF were docked with SARS-CoV-2 and angiotensin converting enzyme II (ACE2). Compound–target network mainly contained 178 compounds and 272 corresponding targets. Key targets contained MAPK3, MAPK8, TP53, CASP3, IL6, TNF, MAPK1, CCL2, PTGS2, etc. There were 522 GO items in GO enrichment analysis (p <.05) and 168 signaling pathways (p <.05) in KEGG, mainly including TNF signaling pathway, PI3K–Akt signaling pathway, NOD-like receptor signaling pathway, MAPK signaling pathway, and HIF-1 signaling pathway. The results of molecular docking showed that baicalein and quercetin were the top two compounds of HSBDF, which had high affinity with ACE2. Baicalein and quercetin in HSBDF may regulate multiple signaling pathways through ACE2, which might play a therapeutic role on COVID-19. [ABSTRACT FROM AUTHOR]

In this work, one three-dimensional periodic composite structure consisting of alumina frame and inscribed nickel spheres is proposed for designing the micron composite porous structure. The finite-difference time domain method is applied for predicting the radiation spectra of proposed composite structure and distribution of absorbed radiative power. The spectral characteristics of composite structure are compared with the hollow ceramic frame structure and stacked metal spheres for analysis of radiative properties of discussed micron composite porous structure, then the effects by changing the number of layers and inner structure are summarized. Strong spectral selectivity is observed, while radiative properties of composite structure are harmonic results of hollow ceramic frame structure and stacked metal spheres. The absorptivity changes with increasing layers hardly, while the reflectivity and transmissivity are affected by number of layers obviously until the number of layers reaches three. When the number of layers exceeds three, the effects of increasing layers are ignorable. Besides, effects on the distribution of absorbed power inside composite porous structure are produced by upper two layers mainly. Furthermore, the radiation spectra are changed by placing hollow ceramic frame layers on the composite structure layer. The proposed composite structure and prediction of radiative properties can be helpful for designing the structure of micron porous materials and regulating the radiative transfer. [ABSTRACT FROM AUTHOR]

Epigallocatechin gallate (EGCG) is a natural phenolic compound found in many plants, especially in green tea, which is a popular and restorative beverage with many claimed health benefits such as antioxidant, anti-cancer, anti-microbial, anti-diabetic, and anti-obesity activities. Despite its great curative potential, the poor bioavailability of EGCG restricts its clinical applcation. However, nanoformulations of EGCG are emerging as new alternatives to traditional formulations. This review focuses on the nanochemopreventive applications of various EGCG nanoparticles such as lipid-based, polymer-based, carbohydrate-based, protein-based, and metal-based nanoparticles. EGCG hybridized with these nanocarriers is capable of achieving advanced functions such as targeted release, active targeting, and enhanced penetration, ultimately increasing the bioavailability of EGCG. In addition, this review also summarizes the challenges for the use of EGCG in therapeutic applications, and suggests future directions for progress. [ABSTRACT FROM AUTHOR]

Primary Objective: This study characterized the acute and chronic effects of tau reduction in traumatic brain injury (TBI). Research Design: A fluid percussion injury (FPI) or a sham-injury was administered to wild type (WT) or tau knockout (Tau-/-) mice. Mice were assigned to a one-week or twelve-week recovery period before behavioral testing and analysis of brain tissue. Methods and Procedures: Mice were tested on the elevated-plus maze, the Y-maze, and rotarod. The twelve-week recovery mice underwent in vivo MRI. Phosphorylated tau in brain tissue was analyzed post-mortem using western blots. Main Outcomes and Results: FPI mice, regardless of genotype, had abnormalities on the elevated-plus maze (a task to assess anxiety-like behavior) at one-week post-injury. However, after twelve-weeks recovery, the Tau-/- mice that were given an FPI were less anxious and had improved motor function compared to their WT counterparts. MRI analysis found that while all FPI mice had brain damage, the Tau-/- mice had larger hippocampal volumes. The WT+FPI mice also had increased phosphorylated tau compared to WT+sham mice at both the one-week and twelve-week recovery times. Conclusion: These findings suggest that tau may play an important role in some of the consequences of TBI, particularly the long-term functional deficits. [ABSTRACT FROM AUTHOR]

Monte Carlo method (MCM) and finite volume method (FVM) are integrated to deal with combined conduction-radiation heat transfer problems in irregular geometries containing gray semitransparent media. The MCM is employed to get radiative heat source using blocked-off and embedded boundary treatments via Cartesian system. The FVM is adopted to solve the energy equation via unstructured grid system. The radiative heat source is implemented in the energy equation through geometrical mapping. The hybrid strategy is first validated regarding both pure radiation and conduction-radiation problems. Then, the features of the two boundary treatments are assessed through solving the conduction-radiation heat transfer problems in irregular geometries. The results show that both of them are highly satisfactory for calculating temperature distribution. In comparison with the embedded boundary treatment, the blocked-off treatment leads to obvious errors in predicting wall radiative heat flux for curved boundaries as well as the boundaries adjacent to the inner curved obstacle. Additionally, the hybrid strategy combined with embedded boundary treatment is promising in eliminating the ray effects. [ABSTRACT FROM AUTHOR]

Interpenetrating phase composites (IPCs) have recently been fabricated using three-dimensional (3D) printingmethods. In a two-phase IPC, the two phases are topologically interconnected and mutually reinforced in the three dimensions. As a result, such IPCs exhibit higher stiffness, strength, and toughness than particleor fiber-reinforced composites. In the current study, three unit cell models for the IPCs with the simple cubic (SC), face-centered cubic (FCC), and body-centered cubic (BCC) microstructures are developed using the meshfree radial point interpolation method. Radial basis functions with polynomial reproduction are applied to construct shape functions, and the Galerkinmethod is employed to formulate discretized equations. These unit cell-based meshfree models are used to evaluate effective elastic properties of 3D printable IPCs. The simulation results are compared with those based on the finite element (FE) method and various analytical bounding techniques in micromechanics, including the Voigt-Reuss, Hashin-Shtrikman, and Tuchinskii bounds. It is found that all of the simulation results for the effective Young's modulus and shear modulus fall between the Voigt-Reuss upper and lower bounds for each IPC considered, with the FE models predicting higher values than the meshfree models. In addition, it is seen that the SCmicrostructure leads to higher effective Young's modulus than the BCC and FCC microstructures. Furthermore, the numerical results reveal that the IPCs with the SC, BCC, and FCC microstructures can be approximated as isotropic materials (with the Zener anisotropic ratio varying between 0.9 and 1.0), with the BCC IPC being the most isotropic one, and the SC IPC being the least isotropic one among the three types of IPCs. [ABSTRACT FROM AUTHOR]

A series of novel arylpyrazole derivatives containing aminomethanephosphonate and phenylfuran moieties were designed, synthesized and characterized by1H NMR,31P NMR and IR spectroscopy and elemental analyses. The single crystal structure of diethyl [5-(4-chlorophenyl)furan-2-yl][3-cyano-1-(2,3,4-trifluorophenyl)-1H-pyrazol-5-ylamino]methanephosphonate (4l) was determined by X-ray diffraction. Preliminary bioassays showed that these phosphonates exhibit satisfactory insecticidal activities againstCulexpipiensandMusca domesticaat 0.1%. In particular, compound4lexhibited a most promising KT50 value, which is superior to that of Dextraltetramethrin® and similar to Prallehtrin®. The structure-activity relationship was also preliminarily investigated. [ABSTRACT FROM PUBLISHER]

A bidirectionally weighted Monte Carlo method has been developed for radiation transfer in participating media. For every two elementary cells, the radiation exchange is expressed as the weighted combination of those obtained from the forward and reverse Monte Carlo methods. And the weight is derived, so that the standard deviation of the radiation exchange is minimized, in contrast to the forward and reverse methods for the same computing cost. Moreover, this method can be applied to complex systems such as that containing highly spectral media. In benchmark solutions, the method was validated and results in less statistical errors than other types of Monte Carlo methods. [ABSTRACT FROM PUBLISHER]

Cell death and survival signaling pathways have opposed but fundamental functions for various cellular processes and maintain cell homeostasis through cross talk. Here we report a novel mechanism of interaction between these two pathways through the cleavage of RNF31 by caspases. RNF31, a component of the linear ubiquitin chain assembly complex (LUBAC), regulates cell survival by inducing linear ubiquitination of NF-kB signaling components. We found that RNF31 is cleaved under apoptosis conditions through various stimulations. The effector caspases caspase 3 and caspase 6 are responsible for this event, and aspartates 348, 387, and 390 were identified as target sites for this cleavage. Cleavage of RNF31 suppressed its ability to activate NF-kB signaling; thus, mutation of cleavage sites inhibited the induction of apoptosis by treatment with tumor necrosis factor alpha (TNF-α). Our findings elucidate a novel regulatory loop between cell death and the survival signal and may provide guidance for the development of therapeutic strategies for cancers through the sensitization of tumor cells to death-inducing drugs. [ABSTRACT FROM AUTHOR]

Conclusion: The sensitive sonotubometry and MATLAB provide a new tool to study the eustachian tube (ET) function and contribute more to reliable data and precise analysis. The levator veli palatini muscle (mLVP) and the salpingopharyngeus muscle (mSP) may, respectively, be the most important and least important muscle for ET function. Objectives: The ET lumen dilation is a result of the contraction of the paratubal muscles, the tensor veli palatini muscle (mTVP), mLVP and mSP. To trace the dynamic ET muscle/lumen activities, the present study aimed to optimize sonotubometry and achieve cross-platform data integration of electromyography (EMG) and sonotubometry using MATLAB (matrix laboratory). Method: Seventeen healthy volunteers (34 ears) were chosen for the concurrent recordings of the paratubal EMG and sonotubogram under dry and water swallowing. Results: The optimized sonotubometry based on computer sound card showed satisfied sensitivity. For both EMGs and sonotubogram, dry swallowing generated significantly greater amplitude and longer duration compared to water swallowing. Moreover, statistically significant differences (p<0.05) were detected in the comparison of the amplitude, duration, and latency for the mTVP, mLVP, and mSP. The mSP activity was the weakest and even inactive in some cases, the mLVP presented the most powerful and long lasting activity during ET-opening. [ABSTRACT FROM AUTHOR]

Objective: Efforts have been made by tissue engineers to create a permissive environment for neural regeneration, and to enhance the efficiency of neural stem cell (NSC) transplantation. However, to acquire sufficient number of seed cells on the material appears to be the main obstacle to constructing functional transplantable NSC-biomaterial complexes. A culture system has been optimized in the current study to maintain the specific characteristics of NSCs/neural progenitor cells (NPCs) on the material and achieve sustaining increased multipotent seed cells. Methods: The PHBHHx film was selected as biomaterial and the surface was firstly modified with NaOH treatment. The NSCs/NPCs isolated from the cerebral cortex of rat embryos were cultured on the treated PHBHHx films in growth medium containing 1%, 5%, and 10% fetal bovine serum (FBS). Then the attachment, survival, proliferation, and differentiation of NSCs/NPCs were assessed. Results: NaOH treatment significantly increased the hydrophilicity of PHBHHx and enhanced NSCs/NPCs attachment. On the treated PHBHHx film, NSCs/NPCs survived well and actively proliferated in the medium containing 1% FBS. After 7-14 days in culture, approximately two-thirds of cells remained as nestin and Sox2 positive NSCs/NPCs. However, in the medium containing 5% and 10% FBS, NSCs/NPCs proliferation was reduced and differentiation, particularly glial differentiation was significantly promoted. Conclusion: Growth medium containing low concentration of FBS is favorable for maintaining the characteristics, in terms of self-renewal and multiple differentiation, of NSCs/NPCs on NaOH-treated PHBHHx films. This could be a useful method to construct functional transplantable NSCs/NPCs-biomaterial complex. [ABSTRACT FROM AUTHOR]

The diatom Pseudo-nitzschja brasiliana Lundholm, Hasle & GA. Fryxell is documented from China for the first time. Strains isolated from southeast coastal waters were characterized using light and electron microscopic observation. All strains were tested for domoic acid, but no toxin was detected. Genetic diversity and phylogenetic relationships of global strains of P. brasiliana were studied to assess intraspecific variation and geographic distribution patterns. Phylogenetic analyses based on the large subunit rDNA gene together with morphological observations show that P. brasiliana from China and other locations worldwide form one well-supported monophyletic dade, with P. americana as its sister. Phylogenetic analyses of internal transcribed spacer (ITS) rDNA sequences show a clear separation between five Asian strains and three European strains. In addition, ITS-2 rDNA secondary structure analyses reveal genetic variation between P. brasiliana strains from Europe and Southeast Asia, namely, a transfer of a base-pair set from a loop in the Asian group to the basis of helix II in the European group and two hemi-compensatory base changes (hemi-CBCs) in helix Ill between one European strain (ICMB-l76) and the other strains. The occurrence of P. brasiliana in China's coastal waters is discussed. [ABSTRACT FROM AUTHOR]

Polystyrene-supported N-phenyl-N-acyl sulfonamide resin was prepared by reacting polystyrene sulfonyl chloride resin with aniline and acylating in pyridine with either acid chlorides or anhydrides. Then, this resin was utilized as a new type of acyl transfer reagent to synthesize the amide library. It was approved to be a more effective acyl transfer reagent with higher amide yields than the polystyrene-supported N-methyl-N-acyl sulfonamide resin and N-benzyl-N-acyl sulfonamide resin. When the phenyl group bonded to the N atom on N-phenyl-N-acyl sulfonamide resin was substituted by the electron withdrawing group or electron donating group, a decreasing amide yield was obtained. N-phenyl-N-acyl sulfonamide resin could be regenerated many times. [ABSTRACT FROM AUTHOR]

By discretizing the medium into many sublayers and employing a linear refractive index approximation for each sublayer, a curve Monte Carlo method is developed to solve the radiative heat transfer in an absorbing and scattering gradient-index medium. The probability models for emission point and radiation transfer path samplings are derived. For an absorbing and isotropic scattering medium with a sinusoidal refractive index distribution, the effects of optical thickness, boundary characteristics, and isotropic scattering on radiative equilibrium temperature and radiative heat flux in the medium are investigated by the method. From the analysis, some valuable information is obtained. [ABSTRACT FROM AUTHOR]

Receptor-interacting protein (RIP) plays a critical role in tumor necrosis factor alpha (TNF-α-indueed NF-κB activation. However, the mechanism by which RIP mediates TNF-α-induced signal transduction is not fully understood. In this study, we reconstituted RIP-deficient Jurkat T cells with a fusion protein composed of full-length MEKK3 and the death domain of RIP (MEKK3-DD). In these cells, MEKK3-DD substitutes for RIP and directly associates with TRADD in TNF receptor complexes following TNF-α stimulation. We found that TNF-α-induced NF-κB activation was fully restored by MEKK3-DD in these cells. In contrast, expression of a fusion protein composed of NEMO, a component of the IκB kinase complex, and the death domain of RIP (NEMO-DD) cannot restore TNF-α-induced NF-κB activation in RIP-deficient cells. These results indicate that the role of RIP is to specifically recruit MEKK3 to the TNF-α receptor complex, whereas the forced recruitment of NEMO to the TNF-α receptor complex is insufficient for TNF-α-induced NF-κB activation. Although MEKK2 has a high degree of homology with MEKK3, MEKK2-DD, unlike MEKK3-DD, also fails to restore TNF-&akpha;-induced NF-κB activation in RIP-deficient cells, indicating that RIP-dependent recruitment of MEKK3 plays a specific role in TNF-α signaling. [ABSTRACT FROM AUTHOR]

CARMA1 (also known as CARD11) is a scaffold molecule and contains a caspase-recruitment domain (CARD) and a membrane-associated guanylate kinase-like (MAGUK) domain. It plays an essential role in mediating CD3/CD28 costimulation-induced NF-κB activation. However, the molecular mechanism by which CARMA1 mediates costimulatory signals remains to be determined. Here, we show that CARMA1 is constitutively associated with the cytoplasmic membrane. This membrane association is essential for the function of CARMA1, since a mutant of CARMA1, CARMA1 (L808P), that is defective in the membrane association cannot rescue CD3/CD28 costimulation-induced NF-κB activation in JPM50.6 CARMA1-deficient T cells. Although CD3/CD28 costimulation effectively induces the formation of the immunological synapse in CARMA1-deficient T cells, the recruitment of protein kinase C-θ (PKC-θ), Bcl10, and IκB kinase β (IKKβ) into lipid rafts of the immunological synapse is defective. Moreover, expression of wild-type CARMA1, but not CARMA1(L808P), restores the recruitment of PKC-θ, Bcl10, and IKKβ into lipid rafts in CARMA1-deficient T cells. Consistently, expression of a mutant CARMA1, CARMA1(ΔCD), that cannot associate with Bcl10 failed to restore CD3/ CD28 costimulation-induced NF-κB activation in JPM50.6 cells, whereas expression of BcI10-CARMA(ΔCD) fusion protein effectively restored this NF-κB activation. Together, these results indicate that CARMA1 mediates CD3/CD28 costimulation-induced NF-κB activation by recruiting downstream signaling components into the immunological synapse. [ABSTRACT FROM AUTHOR]

Two numerical methods for solving the radiative heat transfer in a gradient index semitransparent slab are compared. The slab is discretized into many sublayers. The constant refractive index assumption in a sublayer and the ray splitting and tracing technique are used in the first method, and the linear approximation of refractive index in a sublayer and the curved ray tracing technique are adopted in the second method. The heat transfer at radiative equilibrium and coupled radiation-conduction are involved in the comparison. The results of the two methods show good agreement, but their calculating efficiencies are found to be quite different. [ABSTRACT FROM AUTHOR]

Poly(A)-binding proteins (PABs) bind to the poly(A) tails of most eukaryotic mRNAs and thereby influence the translational efficiency as well as the stability of the mRNAs thus bound. Compared with the data on yeast PAB, relatively little is known about the functions of PABs in higher plants. The cDNA encoding PAB was cloned by the method of "virtual subtraction" from carrot somatic embryos cultured with different sucrose concentrations. Sequence alignment reveals a significant homology between the deduced amino acid sequence of DcPAB and those of other PAB s. The deduced sequence consists of 658 amino acids with a calculated molecular weight of 71.9 kDa. The cDNA has been expressed as a recombinant protein in Escherichia coli . The differential expression of DcPAB under different conditions suggests a potently unique role in the development of carrot somatic embryo. [ABSTRACT FROM AUTHOR]

A preface to the journal "Mechanics of Advanced Materials & Structures" is presented.

A preface for the November 2008 issue of "Mechanics of Advanced Materials and Structures," a special issue about micromechanics and nanomechanics, is presented.

Bcl10 (B-cell lymphoma 10) is an adaptor protein comprised of an N-terminal caspase recruitment domain and a C-terminal serine/threonine-rich domain. Bcl10 plays a critical role in antigen receptor-mediated NF- B activation and lymphocyte development and functions. Our current study has discovered that T-cell activation induced monophosphorylation and biphosphorylation of Bcl10 and has identified S138 within Bcl10 as one of the T-cell receptor-induced phosphorylation sites. Alteration of S138 to an alanine residue impaired T-cell activation-induced ubiquitination and subsequent degradation of Bcl10, ultimately resulting in prolongation of TCR-mediated NF-B activation and enhancement of interleukin-2 production. Taken together, our findings demonstrate that phosphorylation of Bcl10 at S138 down-regulates Bcl10 protein levels and thus negatively regulates T-cell receptor-mediated NF- B activation. [ABSTRACT FROM AUTHOR]

Type I insulin-like growth factor receptor (IGF-IR) can transform mouse fibroblasts; however, little is known about the transforming potential of IGF-IR in human fibroblasts or epithelial cells. We found that overexpression of a constitutively activated IGF-IR (CD8-IGF-IR) was sufficient to cause transformation of immortalized human mammary epithelial cells and growth in immunocompromised mice. Furthermore, CD8-IGF-IR caused cells to undergo an epithelial-to-mesenchymal transition (EMT) which was associated with dramatically increased migration and invasion. The EMT was mediated by the induction of the transcriptional repressor Snail and downregulation of E-cadherin. NF-κ was highly active in CD8-IGF-IR-MCF10A cells, and both increased levels of Snail and the EMT were partially reversed by blocking NF-κ or IGF-IR activity. This study places IGF-IR among a small group of oncogenes that, when overexpressed alone, can confer in vivo tumorigenic growth of MCF10A cells and indicates the hierarchy in the mechanism of IGF-IR-induced EMT. [ABSTRACT FROM AUTHOR]