Based on the strain gradient theory, we present a microstructure-dependent Bernoulli–Euler model to analyze the vibration and stability of microscale pipes conveying fluid. The equation of motion and ...boundary conditions are derived using Hamilton’s principle. The proposed strain gradient beam model contains three material length scale parameters to capture the size effect. This new model may be reduced to the modified couple stress beam model when two of these three material length scale parameters vanish and may be reduced to the classical beam model in the absence of all the material length scale parameters. From the numerical calculations for micropipes with both ends positively supported, it is found that the natural frequency and the critical flow velocity are size-dependent. The results show that the microscale pipe displays remarkable size effect when its outside diameter becomes comparable to the material length scale parameter, while the size effect is almost diminishing as the diameter is far greater than the material length scale parameter. Moreover, the size effect predicted by the current strain gradient beam model is stronger than that predicted by the modified couple stress beam model, since two other material length scale parameters have been accounted for in the former.
Financing firms in India Allen, Franklin; Chakrabarti, Rajesh; De, Sankar ...
Journal of financial intermediation,
07/2012, Letnik:
21, Številka:
3
Journal Article
Recenzirano
Odprti dostop
With extensive cross-country datasets and India firm samples, as well as our own surveys of small and medium firms, we examine the legal and business environments, financing channels, and growth ...patterns of different types of firms in India. Despite the English common-law origin and a British-style judicial system, Indian firms face weak investor protection in practice and poor institutions characterized by corruption and inefficiency. Alternative finance, including financing from all nonbank, nonmarket sources, and generally backed by nonlegal mechanisms, constitutes the most important form of external finance. Bank loans provide the second most important external financing source. Firms with access to bank or market finance are not associated with higher growth rates. Our results indicate that bank and market finance is not superior to alternative finance in fast-growing economies such as India.
We evaluate the efficiency of capital deployment for acquiring firms
before
mergers and acquisitions (M&As), defined as the return on invested capital net of the cost of capital, and link this ...measure to firms’ postacquisition performance. Acquirers with higher preacquisition net returns on investment have superior long-run operating and stock performance than do acquirers with lower returns. Acquirers with low net returns on investment also underperform matching nonacquirers. The relationship between preacquisition investment return and postacquisition performance is weakened when chief executive officer turnover occurs after deal completion. These results imply that managerial ability in deploying capital and creating value for shareholders persists through M&As.
The online appendix is available at
https://doi.org/10.1287/mnsc.2017.2766
.
This paper was accepted by Wei Jiang, finance.
Background
Ileal J-pouch anal anastomosis (J-IPAA) is the standard approach for patients requiring restorative proctocolectomy due to familial adenomatous polyposis (FAP) or ulcerative colitis (UC). ...To obviate the risk of a J-tip leak, we modified the J-pouch with a D-pouch anal anastomosis (D-IPAA) designed to eliminate the ileal stump. The aim of our study was to evaluate the feasibility, safety and medium-term functional outcomes of D-IPAA.
Methods
A retrospective comparison was made between D-IPAA and J-IPAA constructions after a restorative proctocolectomy. Clinical data were collated between October 2014–March 2018 recording operation duration, pouch construction time, pouch volume, intraoperative estimated blood loss, complication rates, readmissions and cumulative length of hospitalization. Continence was assessed at the final visit with the Wexner Cleveland Clinic Score along with the Cleveland Global Quality of Life (CGQL) scale.
Results
A total of 97 patients with FAP (
n
= 28) and UC (
n
= 69) who had J-IPAA (
n
= 54) or D-IPAA (
n
= 43) after proctocolectomy were identified. Patients were well matched with no differences noted in the intraoperative variables between the J- and D-pouch groups. The D-pouch construction time was shorter than that for a standard J-pouch. There was no difference in major or minor complications between groups. A pouch leak developed in each group: a cutaneous fistula from J tip leak in the J-IPAA group and a pouch-vaginal fistula from the IPAA the D-IPAA group. Clinical outcomes (the number of bowel movements) were equivalent in the two groups with the Wexner score significantly improving within each group up to 2.5 years and with improvement in the CGQL after surgery.
Conclusions
The D-pouch construction is safe and feasible for patients with UC and FAP with good functional outcome over the medium term and the potential to reduce the risk of pouch leaks.
Two strains of Aeromonas salmonicida, YK and BG, were isolated from largemouth bronze gudgeon and northern whitefish in China, and identified as A. salmonicida subsp. salmonicida based on ...phylogenetic analysis of vapA and 16S rRNA gene sequences. YK and BG originated from freshwater fish, one of which belonged to the cyprinid family, and the strains showed a difference in virulence. Subsequently, we performed whole genome sequencing of the strains, and comparison of their genomic sequences to the genome of the A449 reference strain revealed various genomic rearrangements, including a new variant of the genomic island AsaGEI in BG, designated as AsaGEI2c. This is the first report on a GEI of A. salmonicida strain from China. Furthermore, both YK and BG strains contained a Tn7 transposon inserted at the same position in the chromosome. Finally, IS-dependent rearrangements on pAsa5 are deemed likely to have occurred, with omission of the resD gene in both strains as well as omission of genes related to the IncF conjugal transfer system in the YK isolate. This study demonstrates that A. salmonicida subsp. salmonicida can infect non-salmonids (cyprinids) in addition to salmonids, and that AsaGEI2c might be useful as a geographical indicator of Chinese A. salmonicida subsp. salmonicida isolates.
Aeromonas salmonicida from China contain a novel genomic island.
•Strain energy density method can be used to investigate the zonal disintegration.•The critical condition of zonal disintegration in deep rock mass is defined.•Stress-fields have wave feature when ...external load is more than critical value.•Rock mass displays elastic behavior when external load is less than critical value.
The deformation and failure modes of the deep rock mass are different from those of the shallow rock mass. Zonal disintegration phenomenon occurs in the deep rock mass, while loosened zone, plastic zone and elastic zone appear successively in the shallow rock mass. It is known that it is necessary to adopt the different support system for the different deformation and failure modes of rock mass. Therefore, it is very significant to define the critical condition of zonal disintegration. In this paper, a non-Euclidean model is proposed to investigate the critical condition of zonal disintegration in deep rock mass. A bulk free energy function of deep rock mass is introduced to describe the effects of microcracks. The standard formalism of non-equilibrium thermodynamics is used to obtain an equation for the non-Euclidean parameter. The relationship between non-Euclidean parameter and stress is established. The critical value of stress for zonal disintegration is derived using strain energy density approach. When the external load is less than the critical value of stress, the mechanical behaviors of rock materials can be simulated using the classical elastic model. In other words, when the external load is less than the critical value, zonal disintegration phenomenon does not occur. When the external load exceeds the critical value of stress, the mechanical behaviors of rock mass can be simulated using the non-Euclidean model, and zonal disintegration phenomenon occurs.
Summary
Background
The co‐stimulatory molecule B7‐H3, a cell surface transmembrane glycoprotein, was assessed for its functional and prognostic role in lichen simplex chronicus (LSC).
Aim
To ...investigate if abnormal expression of the co‐stimulatory molecule B7‐H3 in LSC is associated with Langerhans cell (LC) expansion.
Methods
We used immunohistochemistry to stain LSC skin tissue, and evaluated if the immunostaining of B7‐H3 and interleukin (IL)‐6 was significantly different.
Results
Our results indicated that B7‐H3 is abnormally expressed in LSC skin tissue and positively regulates LC expansion. We also found that IL‐6 might modulate B7‐H3 expression. Moreover, LC expansion in LSC leads to the proliferation of T cells.
Conclusions
Our study indicates the potential value of immunotherapy as a treatment for LSC.
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