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Distinct, periodic arc-shaped ripples are observed on the surface of the weld bead in almost any welded components which have a significant effect on weld quality. This article presents the complex transport phenomena and their effect on the formation of ripples in three-dimensional moving gas metal arc welding. The transient distributions of the melt flow velocity and temperature in the weld pool, weld pool shape and dynamics, and solidified weld bead are calculated. It is found that the surface ripples are formed by the interplay between the up-and-down weld pool dynamics, caused mainly by the periodic droplet impingements, and the rate of weld pool solidification. The effects of various welding parameters, including the welding current, droplet size, droplet frequency, droplet impinging velocity, and travel speed on the pitch (distance between two ripples) and height of the ripple are investigated. This study provides fundamental understanding to the underlying physics that cause the formation of ripples with different pitches and heights. [ABSTRACT FROM AUTHOR]

Byline: S. M. Liao, T. S. Zhao Laminar convective heat transfer of supercritical carbon dioxide flowing in miniature vertical tubes was investigated numerically. Typical velocity profiles, temperature profiles, Nusselt numbers, and skin-friction coefficients for circular tubes having diameters of 0.5, 0.7, 1.4 and 2.16 mm, under both cooling and heating conditions, with and without gravity, were obtained. It is shown that for the supercritical carbon dioxide tube flow, hydrodynamically and thermally fully developed flow regions can be reached only when the fluid and the pipe wall are under the thermal equilibrium condition, which usually occurs at a location a long way downstream from the tube inlet (x/d > 1000). In addition, it has been revealed that buoyancy effects are significant for all cases considered, even for small tubes and at high Reynolds numbers. The results of this paper are of significance for the design of high efficiency compact supercritical carbon dioxide heat exchangers.

We retrospectively analyzed therapy efficacy and the adverse reactions of 10 patients suffering from systemic lupus erythematosus (SLE) with intestinal involvement treated with rituximab (RTX). Patients were hospitalized in the Department of Rheumatology and Immunology of the First Medical Center of PLA General Hospital from January 2015 to January 2023. Among the 10 patients, two were men and eight were women. The age of the cohort was (41.9±8.8) years. The age at disease onset was (28.8±9.2) years. The total course of the SLE diagnosis was(109.6±59.9) months. The course of the diagnosis of SLE with intestinal involvement was (89.3±50.2) months. The time from the appearance of intestinal symptoms to the diagnosis of SLE with intestinal involvement was 1.5 (1.0,8.0) months. The time from the diagnosis of SLE with intestinal involvement to RTX use was 13.0 (1.0,46.3) months. Follow-up duration after application of RTX treatment was (55.3±28.4) months. There were five cases of abdominal pain, four cases of abdominal distension, nine cases of diarrhea, three cases of nervous-system involvement, nine cases of lupus nephritis, and seven cases of serositis. All 10 patients underwent computed tomography and radiology of the abdomen. Eight patients had intestinal-wall edema, seven suffered intestinal dilation, four had target signs, three suffered congestion of mesenteric blood vessels, eight had increased mesenteric-fat density, and six had false intestinal obstruction. All 10 patients showed a low level of complement C3 (250-750 mg/L). Nine cases showed a low level of complement C4 (10-90 mg/L). The SLE disease activity index 2000 (SLEDAI-2K) at baseline in 10 patients was 20.5 (17.8, 30.0). After receiving RTX (0.5 g: day 1, day 14, or 375 mg/m 2 : day 1, day 14) induction treatment, the intestinal symptoms of 10 cases were relieved completely. Four patients had adverse reactions, of which three received a high-dose glucocorticoid combined with RTX treatment simultaneously. Adverse reactions manifested mainly as a reduced level of IgG and infection with herpes simplex virus in one case, reduced level of IgG and lung infection in one patient, lung infection in one case, and reduced IgG level in one patient. RTX may an efficacious treatment strategy for patients suffering from refractory SLE with intestinal involvement.

The study aimed to analyze the efficacy and safety of rituximab in the treatment of 23 cases of lupus nephritis and explore the prospect of half-dose rituximab in lupus nephritis treatment. Twenty-three patients with lupus nephritis hospitalized in the Department of Rheumatology and Immunology at the First Medical Center of the PLA General Hospital from May 2013 to December 2021 were selected. Eighteen patients received rituximab 375 mg/m 2 on the first and 14th days, 5 patients received 500 mg of rituximab on the first and 14th days, and rituximab was used as needed 6 months later. Methylprednisolone (80-120 mg) was given together with rituximab. Afterward, 1 mg/kg prednisone was used for 4 weeks, which was progressively tapered to maintenance doses or discontinued. B lymphocyte level, renal function, 24-h urine protein level, and systemic lupus erythematosus (SLE) disease activity index 2000 (SLEDAI2K) score before and after treatment were recorded. The efficacy and adverse reactions were analyzed. The results showed that 11 patients suffered from renal insufficiency [creatinine (162.7±58.6) μmol/L ] at baseline, while the creatinine level of 9 patients returned to normal 12 months after the treatment [ (66.3±10.1)μmol/L ]. Normal renal function of the other 12 patients was maintained during treatment. After 12 months, the 24-h urine protein level decreased from 4.00 (2.00,6.80) g in the baseline period to 0.10 (0.08,0.40) g. SLEDAI2K score decreased from 22 (18,26) in the baseline period to 3 (0,6) 12 months after the treatment. The B lymphocyte level reached 0.00 (0.00,0.01)% at 3 months. Of 23 patients, 13 patients achieved complete remission, and 7 patients achieved partial remission after 6 months of rituximab treatment. Five patients experienced adverse reactions related to rituximab, including 1 case of transfusion reaction, 1 case of perioral herpes with pulmonary infection, and 3 cases of decreased IgG levels. Therefore, rituximab regimen used in this study can be an effective treatment strategy for lupus nephritis.

Objective: To analyze the genetic relationship of Dendrobium and design a specific primer to differentiate Dendrobium candidum effectively., Method: Random amplified polymorphic DNA (RAPD) technique was used to analyze the genetic relationships of 26 species of Dendrobium and one species of Ephemerantha. Dendrogram was constructed by UPGMA. According to the sequence of DNA fragment selected, Sangon 18 primer had been extended from 3' extreme to 20 bp in order to form a specific primer., Result and Conclusion: This primer can be used to distinguish Dendrobium candidum from other Dendrobium effectively. Such a technique provides a new way for the identification of Chinese traditional medicines.

Here we report the identification of a novel PMA-inducible IkappaB kinase complex, distinct from the well-characterized high-molecular weight IkappaB kinase complex containing IKKalpha, IKKbeta, and IKKgamma. We have characterized one kinase from this complex, which we designate IKKepsilon. Although recombinant IKKepsilon directly phosphorylates only serine 36 of IKBalpha, the PMA-activated endogenous IKKepsilon complex phosphorylates both critical serine residues. Remarkably, this activity is due to the presence of a distinct kinase in this complex. A dominant-negative mutant of IKKepsilon blocks induction of NF-kappaB by both PMA and activation of the T cell receptor but has no effect on the activation of NF-KB by TNFalpha or IL-1. These observations indicate that the activation of NF-kappaB requires multiple distinct IkappaB kinase complexes, which respond to both overlapping and discrete signaling pathways.

Two cyclin-dependent kinases have been identified in yeast and mammalian RNA polymerase II transcription initiation complexes. We find that the two yeast kinases are indistinguishable in their ability to phosphorylate the RNA polymerase II CTD, and yet in living cells one kinase is a positive regulator and the other a negative regulator. This paradox is resolved by the observation that the negative regulator, Srb10, is uniquely capable of phosphorylating the CTD prior to formation of the initiation complex on promoter DNA, with consequent inhibition of transcription. In contrast, the TFIIH kinase phosphorylates the CTD only after the transcription apparatus is associated with promoter DNA. These results reveal that the timing of CTD phosphorylation can account for the positive and negative functions of the two kinases and provide a model for Srb10-dependent repression of genes involved in cell type specificity, meiosis, and sugar utilization.

The RNA polymerase II holoenzyme consists of RNA polymerase II, a subset of general transcription factors, and regulatory proteins known as SRB proteins. The genes encoding SRB proteins were isolated as suppressors of mutations in the RNA polymerase II carboxy-terminal domain (CTD). The CTD and SRB proteins have been implicated in the response to transcriptional regulators. We report here the isolation of two new SRB genes, SRB10 and SRB11, which encode kinase- and cyclin-like proteins, respectively. Genetic and biochemical evidence indicates that the SRB10 and SRB11 proteins form a kinase-cyclin pair in the holoenzyme. The SRB10/11 kinase is essential for a normal transcriptional response to galactose induction in vivo. Holoenzymes lacking SRB10/11 kinase function are strikingly deficient in CTD phosphorylation. Although defects in the kinase substantially affect transcription in vivo, purified holoenzymes lacking SRB10/11 kinase function do not show defects in defined in vitro transcription systems, suggesting that the factors necessary to elicit the regulatory role of the SRB10/11 kinase are missing in these systems. These results indicate that the SRB10/11 kinase is involved in CTD phosphorylation and suggest that this modification has a role in the response to transcriptional regulators in vivo.