脑库 Laboratoire工作室

Le Laboratoire是一个多领域人士参与的设计实验室性质的组织,一群有着不同背景的科学家、艺术家、设计师聚在一起进行实验和研发,将艺术(Art)、科学(Science)和技术(technology)的力量结合在一起。作为艺术科学(artscience)的创新发生地,Labor     

To Empower or Not to Empower Your Sales Force? An Empirical Examination of the Influence of Leadership Empowerment Behavior on Customer Satisfaction and Performance.

This research focuses on the impact of leadership empowerment behavior (LEB) on customer service satisfaction and sales performance, as mediated by salespeople's self-efficacy and adaptability. Moreover, the authors propose an interactive relationship whereby LEB will be differentially effective as a function of employees' empowerment readiness. The authors' hypotheses are tested using survey data from a sample of 231 salespeople in the pharmaceutical field, along with external ratings of satisfaction from 864 customers and archival sales performance information. Results indicated that contrary to popular belief, employees with low levels of product/industry knowledge and low experience benefit the most from leadership behaviors that are empowering, whereas high-knowledge and experienced employees reap no clear benefit. The authors conclude with directions for future research and application. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dielectric and viscoelastic studies of curing epoxy-amine model systems

Summary The curing of different epoxy-amine model systems which present only gelification and/or vitrification processes has been followed with the evolution of their viscoelastic and electrical behaviours during the network formation. Some attempts are performed to correlate the significant evolution of the mechanical and electrical parameters with the physico-chemical changes of these well defined chemical systems during their hardening and complete curing.     

Ca2+ channel beta3 subunit enhances voltage-dependent relief of G-protein inhibition induced by muscarinic receptor activation and Gbetagamma

The Ca2+ channel beta subunit has been shown to reduce the magnitude of G-protein inhibition of Ca2+ channels. However, neither the specificity of this action to different forms of G-protein inhibition nor the mechanism underlying this reduction in response is known. We have reported previously that coexpression of the Ca2+ channel beta3 subunit causes M2 muscarinic receptor-mediated inhibition of alpha1B Ca2+ currents to become more voltage-dependent. We report here that the beta3 subunit increases the rate of relief of inhibition produced by a depolarizing prepulse and also shifts the voltage dependency of this relief to more hyperpolarized voltages; these effects are likely to be responsible for the reduction of inhibitory response of alpha1B channels to G-protein-mediated inhibition seen after coexpression of the Ca2+ channel beta3 subunit. Additionally, the beta3 subunit alters the rate and voltage dependency of relief of the inhibition produced by coexpressed Gbeta1gamma1, in a manner similar to the changes it produces in relief of M2 receptor-induced inhibition. We conclude that the Ca2+ channel beta3 subunit reduces the magnitude of G-protein inhibition of alpha1B Ca2+ channels by enhancing the rate of dissociation of the G-protein betagamma subunit from the Ca2+ channel alpha1B subunit.     

Rubber band ligation of hemorrhoids: relapse as a function of time

Rubber band ligation is a well established treatment of internal second-degree hemorrhoids. Up to now, the long-term results (> 5 years) of this method have not been assessed. The aim of this study was to determine the long-term success rate of rubber band ligation in patients with a first episode of second-degree hemorrhoids not responding to medical treatment (local cream with laxative). A total of 92 patients who were treated between 1979 and 1997 for second-degree hemorrhoids responded to a questionnaire. The need for complementary conservative (sclerotherapy, cryotherapy or rubber band ligation) or surgical treatment was considered indicative of relapse. The collected data were analyzed according to the Kaplan-Meier method. The average follow-up time was 5.6 years. There were 21 patients who suffered a relapse. The probability of successful treatment was 0.77 (range: 0.67-0.88) after 5 years and 0.68 (range: 0.5-0.86) after 10.6 years. We conclude that rubber band ligation represent an efficient long-term treatment for second-degree hemorrhoids. Approximately two thirds of the patients are cured after 5 years and more than a half after 10 years.     

The common nodABC genes of Rhizobium meliloti are host-range determinants

Symbiotic bacteria of the genus Rhizobium synthesize lipo-chitooligosaccharides, called Nod factors (NFs), which act as morphogenic signal molecules on legume hosts. The common nodABC genes, present in all Rhizobium species, are required for the synthesis of the core structure of NFs. NodC is an N-acetylglucosaminyltransferase, and NodB is a chitooligosaccharide deacetylase; NodA is involved in N-acylation of the aminosugar backbone. Specific nod genes are involved in diverse NF substitutions that confer plant specificity. We transferred to R. tropici, a broad host-range tropical symbiont, the ability to nodulate alfalfa, by introducing nod genes of R. meliloti. In addition to the specific nodL and nodFE genes, the common nodABC genes of R. meliloti were required for infection and nodulation of alfalfa. Purified NFs of the R. tropici hybrid strain, which contained chitin tetramers and were partly N-acylated with unsaturated C16 fatty acids, were able to elicit nodule formation on alfalfa. Inactivation of the R. meliloti nodABC genes suppressed the ability of the NFs to nodulate alfalfa. Studies of NFs from nodA, nodB, nodC, and nodI mutants indicate that (i) NodA of R. meliloti, in contrast to NodA of R. tropici, is able to transfer unsaturated C16 fatty acids onto the chitin backbone and (ii) NodC of R. meliloti specifies the synthesis of chitin tetramers. These results show that allelic variation of the common nodABC genes is a genetic mechanism that plays an important role in signaling variation and in the control of host range.     

Prevention of autoimmune destruction of syngeneic islet grafts in spontaneously diabetic nonobese diabetic mice by a combination of a vitamin D3 analog and cyclosporine

BACKGROUND: Type 1 diabetes is characterized by the presence of an autoimmune memory, responsible for the destruction of even syngeneic islet grafts. This recurrence of autoimmunity is partly responsible for the need of extensive immunosuppression in pancreas and islet transplantation in type 1 diabetic patients. The aim of the study was to evaluate the capacity of a 20-epi-analog of vitamin D3, KH1060, both alone and in combination with cyclosporine (CsA) to prevent diabetes recurrence in syngeneic islet grafts in nonobese diabetic (NOD) mice. METHODS: Spontaneously diabetic NOD mice grafted with syngeneic islets (n=500) under the kidney capsule were treated with KH1060, CsA, or a combination of both drugs from the day before transplantation until recurrence or 60 days after transplantation. RESULTS: Vehicle-treated mice showed a recurrence of diabetes in 100% of cases (n=17) within 4 weeks. Treatment with high doses of CsA (15 mg/kg/day) or KH1060 (1 microg/kg/2 days) significantly prolonged islet survival (60 days and 50 days, respectively, versus 9.5 days in controls; P<0.001 and P<0.0001). Mice treated with subtherapeutical doses of both drugs combined (KH1060 0.5 microg/kg/2 days + CsA 7.5 mg/kg/day) had significant prolongation of graft survival (48 days; P<0.001) and more importantly, four of five mice that were still normoglycemic 60 days after transplantation showed no recurrence after discontinuation of all treatment. Histology of the grafts of control and combination-treated mice demonstrated that graft infiltration and islet destruction were less severe in grafts of combination-treated mice. Cytokine mRNA analysis in the grafts 6 days after transplantation revealed a clear suppression of interleukin-12 and T helper 1 cytokines and higher levels of interleukin-4 in combination-treated mice. CONCLUSIONS: KH1060, an analog of 1,25(OH)2D3, delays autoimmune disease recurrence after syngeneic islet transplantation in NOD mice, both alone and especially in combination with CsA, possibly restoring tolerance to beta cells in 30% of cases.     

Gambling for the mnemonically impaired

We obtain asymptotically tight bounds on the maximum amount of information that a single bit of memory can retain about the entire past. At each of n successive epochs, a single fair bit is generated and a one-bit memory is updated according to a family of memory update rules (possibly probabilistic and time-dependent) depending only on the value of the new input bit and on the current state of the memory. The problem is to estimate the supremum over all possible update rules of the minimum mutual information between the state of the memory at time (n + 1) and each of the previous n input bits. We show that this supremum is asymptotically equal to 1/(2n² ln 2) bit, as conjectured by Venkatesh and Franklin (1991). We use this result to derive asymptotically sharp estimates of related maximin correlations between the memory and the input bits, thus resolving two more questions left open by Venkatesh and Franklin and by Komlos et al. (1993). Finally, we generalize the results to the case of an m-bit memory, again obtaining asymptotically tight bounds in many cases