Traumatic nerve injuries result in devastating loss of neurologic function with unpredictable functional recovery despite optimal medical management. After traumatic nerve injury and denervation, ...regenerating axons must traverse a complex environment in which they encounter numerous barriers on the way to reinnervation of their target muscle. Outcomes of surgical intervention alone have unfortunately reached a plateau, resulting in often unsatisfactory functional recovery. Over the past few decades, many improvements were developed to supplement and boost the results of surgical repair. Biological optimization of Schwann cells, macrophages, and degradation enzymes have been studied due to the key roles of these components in axonal development, maintenance and response to injury. Moreover, surgical techniques such as nerve grafting, conduits, and growth factor supplementation are also employed to enhance the microenvironment and nerve regeneration. Yet, most of the roadblocks to recovery after nerve injury remain unsolved. These roadblocks include, but are not limited to: slow regeneration rates and specificity of target innervation, the presence of a segmental nerve defect, and degeneration of the target end-organ after prolonged periods of denervation. A recognition of these limitations is necessary so as to develop new strategies to improve functional regeneration for these life changing injuries.
•Surgical intervention alone does not provide satisfactory nerve repair results.•Injured nerves encounter barriers that limit their ability to regenerate.•Denervation atrophy of target tissue is associated with peripheral nerve repair and regeneration.
•ESG performance substantially reduces opportunistic EM behavior of firms.•Civil law code and superior creditor rights negatively moderate the ESG-EM relationship.•ESG engagement creates the trust ...and support for the firm in the eyes of stakeholders and therefore they accept the firm's performance and strategies and ensure the continuity of the firm alleviating the need to manipulate actual earnings.
This study examines whether environmental, social, and governance (ESG) engagement affects firms’ earnings management (EM) behavior in a multicountry set up. Employing the Tobit and panel regression framework and co`nsidering performance-matched measure of EM, we show that ESG performance substantially reduces opportunistic firms’ EM behavior. Moreover, the civil law code and superior credit rights negatively moderate the ESG–EM relationship. Empirical findings are robust and survive the use of alternative methodology and endogeneity test.
This paper describes how matrix converters (MCs), one at each side of a three-phase open-end-winding ac machine, achieve the following features simultaneously: 1) machine phase voltage up to 1.5 ...times the input phase voltage in the linear modulation mode, therefore extending the rated torque operation region to 150% of the rated speed of the machine; 2) peak voltage stress across the slot insulation which is limited to the peak of input phase voltage, i.e., a factor of at least √3 lower as compared to the conventional back-to-back converter; 3) controllable grid power factor to be leading, lagging, or unity; and 4) elimination of the instantaneous common-mode voltage at the machine terminals, therefore eliminating the bearing current due to switching common-mode voltage and reduction in the conducted electromagnetic interference. To simultaneously achieve the aforementioned capabilities, a space vector pulsewidth modulation technique is described in which the MCs are modulated using only rotating space vectors. A hardware prototype of the drive system is built. Experimental results from this hardware prototype verify the operation and claims of the drive system.
Electric drives with open-end winding ac machines offer certain advantages over drives with star- or delta-connected machines. Such drives have been recently considered for some applications such as ...electric vehicles. Circulating currents have been experimentally observed in such open-end winding ac drives. These currents have the effect of increasing conduction losses in the stator winding resistance of the ac machine. Two major causes for these currents have been identified as device voltage drops in power semiconductor devices and dead time used for shoot-through current protection. These effects are analyzed, and a mathematical description for predicting their severity is provided. Experimental results are presented that support the theory. The theory developed should be useful for devising solutions for this problem such as the design of common-mode filters. Two methods of suppressing the circulating currents are also outlined, and their experimental results are presented.
•Firm internationalization mediates financial performance through social and environmental performance.•High board independence positively mediates financial performance of firms with low ...internationalization through CSP.•Lower proportion of women directors in firm-board also positively mediates financial performance of firms with low internationalization through CSP.
The current study explores the interlinkage between corporate social, environmental performance (CSP) and financial performance of a firm, mediated by its global exposure and corporate governance. We conduct a dynamic fixed effect 2SLS-IV analysis on a comprehensive multi-country data-set and find that financial performance is not significantly impacted by CSP but there is a positive influence when it is mediated by lower internationalization. We also find that a more independent board lowers such value-destroying managerial activities, while the presence of women directors on board, dampens that positive influence of low internationalisation in strengthening financial performance through higher CSP.
Purpose>The authors examine the stability of dividend payout and the consistency in its predictability using sample of firms from 18 different countries amid their prevailing heterogeneous formal ...institutions (such as the legal system, corporate governance), the distinct state of economic development (developing vs developed) and changing times (during the crisis vs the noncrisis periods).Design/methodology/approach>The authors use tobit regression models with distinct specifications for the authors’ investigations. The authors alternately analyze the study’s results using Fama–Macbeth (FM) (1973) and generalized least square (GLS) regressions.Findings>The authors show a sharply declining stability in dividend payout with time using DeAngelo and Roll’s (2015) framework. In terms of predictive consistency, the authors report that only a few idiosyncratic factors predict dividends consistently, and these results hold qualitatively true across the robustness analysis. The firm's liquidity appears to be the most consistent predictor of dividends payout, whereas firm's size being on the other extreme. The results signify that the idiosyncratic factors that matter for firm's dividend policy are not country specific. Instead, it reveals commonality of predictors grounded on characteristics of countries such as legal environment, investor's protection, economic state (ES) and economic cycle.Originality/value>The authors contribute to the dividends literature by providing the evidence of dividend instability through time and disapproving the stylized fact of sticky dividends. Besides, the authors provide international evidence of inconsistent predictability of dividends.
In rheumatoid arthritis (RA), inflammatory cytokines play a pivotal role in triggering abnormal osteoclastogenesis leading to articular destruction. Recent studies have demonstrated enhanced levels ...of interleukin-9 (IL-9) in the serum and synovial fluid of patients with RA. In RA, strong correlation has been observed between tissue inflammation and IL-9 expression in synovial tissue. Therefore, we investigated whether IL-9 influences osteoclastogenesis in patients with RA. We conducted the study in active RA patients. For inducing osteoclast differentiation, mononuclear cells were stimulated with soluble receptor activator of NF-kB ligand (sRANKL) and macrophage-colony-stimulating factor (M-CSF) in the presence or absence of recombinant (r) IL-9. IL-9 stimulation significantly enhanced M-CSF/sRANKL-mediated osteoclast formation and function. Transcriptome analysis revealed differential gene expression induced with IL-9 stimulation in the process of osteoclast differentiation. IL-9 mainly modulates the expression of genes, which are involved in the metabolic pathway. Moreover, we observed that IL-9 modulates the expression of matrix metalloproteinases (MMPs), which are critical players in bone degradation. Our results indicate that IL-9 has the potential to influence the structural damage in the RA by promoting osteoclastogenesis and modulating the expression of MMPs. Thus, blocking IL-9 pathways might be an attractive immunotherapeutic target for preventing bone degradation in RA.
Since the last update on nerve conduits and allograft in 2000, investigations have established the efficacy of these alternatives to autograft in the repair of small sensory neural gaps. However, ...limited insights into the biology of the regenerating nerve continue to preclude intelligent conduit design. Ongoing discoveries in neuroscience and biomaterial engineering hold promise for the eventual development of allograft and conduits with potential of surpassing nerve autografts in clinical efficacy. In this review, we summarize the history, recent advances, and emerging developments in nerve conduits and allograft.
Fatty degeneration of chronically injured muscle is a commonly recognized consequence of massive rotator cuff tears. Current surgical treatments are unable to alter or reverse the progression of ...fatty degeneration and are associated with poor functional outcomes in these patients. Therefore, a better understanding of the pathophysiology of fatty degeneration is required. As such, recent discoveries in stem cell biology and new animal models have significantly advanced our understanding of the cellular and molecular basis of fatty degeneration. Future studies will facilitate development of novel treatments to prevent the progression of fatty degeneration and improve muscle regeneration in patients with massive rotator cuff tears.
PDF
