The fructose 6-phosphate (Fru-6P) saturation curve for phosphofructokinase (PFK) from E. coli is sigmoidal in the presence of saturating MgATP levels, while the corresponding curve for B. stearothermophilus PFK is essentially hyperbolic. Sigmoidality can be due to apparent cooperativity arising from the kinetic mechanism of an enzyme. We have determined the kinetic mechanism of B. stearothermophilus PFK (BsPFK). BsPFK was found to obey a non rapid-equilibrium random mechanism similar to the one E. coli PFK (EcPFK) follows. Substrate inhibition by MgATP (...) was observed. We propose that substrates bind to BsPFK through two alternative pathways, one of which is slower. The substrate inhibition arises in part from reaction flux through the slower pathway. Although EcPFK and BsPFK obey similar kinetic mechanisms, they are inhibited differently by MgATP: EcPFK is profoundly inhibited, BsPFK only weakly. The structural basis for this difference could be closure of the active site via a conformational transition that occurs in EcPFK, but not BsPFK. To investigate the importance of this transition for MgATP inhibition of EcPFK, we have constructed a chimeric enzyme (ChiPFK) that contains the "rigid" ATP-binding domain of BsPFK grafted onto the remainder of the EcPFK subunit. Our results indicate that ChiPFK is locked in an "open" structure resembling the activated form of EcPFK. It is insensitive to heterotropic regulation. Nevertheless, ChiPFK exhibits residual cooperativity. Possible explanations for the cooperativity are discussed. The 6F loop is proposed to be important in PFK allosteric behavior. Residues along the loop are largely conserved between BsPFK and EcPFK, except for 161, which is a glutamate in BsPFK, and a glutamine in EcPFK. Using site-directed mutagenesis, Glu 161 of BsPFK has been changed to glutamine and alanine. Similarly, Gin 161 of EcPFK has been changed to glutamate, arginine and alanine. Of the five mutants, one, QA161, was particularly interesting. Though activated normally by GDP, it was completely insensitive to PEP inhibition. This indicates that the hydrogen-bonding ability of residue 161 is critical for PEP inhibition of EcPFK, and that GDP activation and PEP inhibition follow different structural pathways. (shrink)

The structure and behaviour of the acetylcholine receptor (AChR) is described, and the evidence that it is an allosteric protein is discussed. The genes for the AChR subunits are subject to a complex set of spatio‐temporal transcriptional controls during development of the motor endplate, and these findings are reviewed here. Finally, the biotechnological prospects suggested by the new data are noted.

Amid the COVID-19 pandemic, fear has run rampant across the globe. To curb the spread of the virus, several governments have taken measures to drastically transition businesses, work, and schooling to virtual settings. While such transitions are warranted and well-intended, these measures may come with unforeseen consequences. Namely, one’s fear of COVID-19 may more readily manifest as aggressive behaviors in an otherwise incognito virtual social ecology. In the current research, a moderated mediation model examined the mechanisms underlying the relation between (...) fear of COVID-19 and overt and relational aggressive online behavior among Chinese college students. Utilizing a large sample of Chinese college students, results indicated that moral disengagement mediated the effect of fear of COVID-19 on college students’ overt and relational online aggressive behavior. A positive family cohesion buffered the effect of moral disengagement on relational aggressive behavior, but only for females. The findings, theoretical contributions, and practical implications of the present paper are also discussed. (shrink)

Expectation of others’ cooperative behavior plays a core role in economic cooperation. However, the dynamic neural substrates of expectation of cooperation are little understood. To fully understand EOC behavior in more natural social interactions, the present study employed functional near-infrared spectroscopy hyperscanning to simultaneously measure pairs of participants’ brain activations in a modified prisoner’s dilemma game. The data analysis revealed the following results. Firstly, under the high incentive condition, team EOC behavior elicited higher interbrain synchrony in the (...) right inferior frontal gyrus than individual EOC behavior. Meanwhile, the IBS in the IFG could predict the relationship between empathy/agreeableness and EOC behavior, and this prediction role was modulated by social environmental cues. These results indicate the involvement of the human mirror neuron system in the EOC behavior and the different neural substrates between team EOC and individual EOC, which also conform with theory that social behavior was affected by internal and external factors. Secondly, female dyads exhibited a higher IBS value of cooperative expectation than male dyads in the team EOC than the individual EOC in the dorsal medial prefrontal cortex, while in the individual EOC stage, the coherence value of female dyads was significantly higher than that of male dyads under the low incentive reward condition in the rIFG. These sex effects thus provide presumptive evidence that females are more sensitive to environmental cues and also suggest that during economic social interaction, females’ EOC behavior depends on more social cognitive abilities. Overall, these results raise intriguing questions for future research on human cooperative behaviors. (shrink)

Egypt, a less affluent, predominantly Muslim country, suffers from numerous forms of environmental pollution, some severe. This study investigates pro-environmental behaviors of citizens in Cairo, Egypt’s largest metropolis, and studies the relationship between pro-environmental behavior and demographic variables, beliefs, values, and religiosity. Analysis shows that three types of pro-environmental behavior are present: Public Sphere, Private Sphere, and Activist Behavior, with the latter occurring less frequently. Importantly, the study identifies an ecocentric value among respondents which is correlated with (...) Public Sphere Behavior. It also confirms earlier research that characterized Egyptians’ perceptions of the environment as being set in the context of health and cleanliness. Religious teachings and religiosity are shown to be associated with pro-environmental behavior, thus lending support to the presence of an Islamic environmental ethic. (shrink)

Generalization of the standard behavior longitudinal genetic factor model for the analysis of interindividual phenotypic variation to a genetic state space model for the analysis of intraindividual variation enables the possibility to estimate subject-specific heritabilities.

Like most other sciences, behavior analysis adopts an assumption of uniformity, namely that principles discovered under controlled conditions apply outside the laboratory as well. Since the boundary between public and private depends on the vantage point of the observer, observability is not an inherent property of behavior. From this perspective, private events are assumed to enter into the same orderly relations as public behavior, and the distinction between public and private events is merely a practical one. Private (...) events play no role in the experimental analysis of behavior, but they permit us to make sense of many commonplace phenomena where controlled observation is impossible but unsystematic data are available. Such interpretive exercises serve both to guide research and to displace occult explanations. (shrink)

To survive in a competitive environment, small and medium enterprises have had to adapt to the digital environment in order to adjust to customer needs globally, particularly in the post-COVID-19 world. The advantages of cloud computing provide opportunities for SMEs with a restricted budget and limited resources. To understand how SMEs adopt cloud computing in a complex digital environment, this study examines how antecedents combine with each other to explain the high adoption of cloud computing. From the perspectives of holism (...) and set theory, we draw on complexity and configuration theories, present a conceptual model including seven antecedents based on the technology-organization-environment framework, and conduct an asymmetric fuzzy-set qualitative comparative analysis. Through an empirical study with 123 Chinese companies, we identify nine combinations of determinant antecedents that lead to the high adoption of cloud computing. The results show that none of the factors are indispensable to explain a high adoption on their own; instead, they are insufficient but necessary parts of the causal combinations that explain a high adoption. This study contributes to the literature on cloud computing adoption by extending current knowledge on how antecedents combine to increase the adoption and identify specific patterns of SMEs for whom these factors are essential and greatly influence their adoption. (shrink)

Electronic technologies, in general, and computer-oriented technologies specifically have had a tremendous impact on all aspects of business. One area of increased concern is the protection of intellectual properties -- notably copyrights -- within the boundaries of the broadly defined technology industry. While the ability to share copyrighted information has always existed at the most basic levels, the advent of the information age has allowed the sharing of this information to take place in potentially greater quantities and without a loss (...) of quality. As such, copying creates a major threat to industries dealing in the production and distribution of copyrightable creations. The focus of this paper is to better understand how the ethical judgments of employees regarding the opportunities to recreate copyrighted works via traditional and newer technologies impact assessments of copying behavior in the workplace. (shrink)

Political participation : the debate so far -- A brief history of agency -- Agency : the neglect of the unconscious -- Talking heads? : the internal political conversation -- Exploring internal political conversations -- Rioting : criminal, political or post-political act?

Several studies have identified entrepreneurship as a key factor in wealth creations in addition to associating certain personality characteristics to its growth. The question is to what extent have these wealth creations performed ethically. The present study is set to explore the cognitive orientation (locus of control, risk taking ability and impression management) and demographic (age and gender) factors that are associated with unethical business. Two hundred and fifty-six owner–managers in the age range of 24 to 68 years participated in (...) the survey study. Male participants accounted for 63.3 per cent, while female participants were 36.7 per cent. The results indicate that risk taking and gender factors were consistently and statistically significant predictors of unethical business across the three groups in this study. The group situation appears to have effect on the individual contribution to unethical business. Implications are drawn from the results, and priorities are established for future research. (shrink)

Attempts to explain human behavior that appeal to economic rationality share many of the same ontological as- sumptions and methodological practices that the so-called ‘adaptationist program’ in biology was criticized for. This program in biology was largely abandoned by biologists as poorly motivated, and replaced with the active testing of both adaptive and non-adaptive hypotheses regarding the spread and maintenance of traits in populations. This development was largely welcome by the biological community, despite having required the development of new (...) tools, both conceptual and method- ological. Many analysts of contemporary microeconomic practice criticize the assumptions and practices employed therein as similarly poorly motivated. Close attention to these criticisms reveal them to have more than superficial similarities to the critiques of adaptationism in biology. These similarities extend to some macroeconomics researchers recent suggestions of ways that hypotheses regarding the causes of people’s actions might be tested; as yet, however, these suggestions have not been embraced by the field as a whole. By attending to the ways in which biological practice has moved beyond the adaptationist program, similar changes in economic practice may be motivated. (shrink)

School-wide positive behavior support is a well-evaluated school approach to promoting a positive school climate and decreasing problem behaviors. Initial implementation is one of the most critical stages of program implementation. In this qualitative study, the initial implementation of SWPBIS in Swedish schools was studied using an implementation model of behavior change as guidance for interviews and analyses. The study makes significant contributions to previous research as little is known of the implementation of SWPBIS in Swedish context. Focus-group (...) interviews were conducted with 59 professionals on implementation teams from nine schools. Themes were extracted according to implementation team members' perceptions and descriptions of how the initial implementation was carried out. The results of this study revealed relevant themes within the three domains of Capability, Opportunity, and Motivation. Core features were found under the themes of knowledge and experience of similar evidence-based programs, process or result orientation, time, manual content, organizational prerequisites, team functioning, implementation leadership, program as a unifying factor, program aligning with staff beliefs, plausible expectations, and emotional reinforcement. Results are discussed in terms of how they can be used in continuing to develop the Swedish model of SWPBIS. Implications regarding implementation in Swedish schools are discussed, as is the applicability of the model of behavior change for studying implementation in schools. (shrink)

'Gaining control' tells the story of how human behavioral capacities evolved from those of other animal species. Exploring what is known about the psychological capacities of other groups of animals, the authors reconstruct a fascinating history of our own mental evolution. The result is a provocative and insightful book.

Our eyes move in response to stimulus statistics, reacting to surprising events, and adapting to predictable ones. Cortical and subcortical pathways contribute to generating context-specific eye-movement dynamics, and oculomotor dysfunction is recognized as one the early clinical markers of Parkinson's disease. We asked if covert computations of environmental statistics generating temporal expectations for a potential target are registered by eye movements, and if so, assuming that temporal expectations rely on motor system efficiency, whether they are impaired in PD. We used (...) a repeating tone sequence, which generates a hazard rate distribution of target probability, and analyzed the distribution of blinks when participants were waiting for the target, but the target did not appear. Results show that, although PD participants tend to produce fewer and less temporally organized blink events relative to healthy controls, in both groups blinks became more suppressed with increasing target probability, leading to a hazard rate of oculomotor inhibition effects. The covert generation of temporal predictions may reflect a key feature of cognitive resilience in Parkinson's Disease. (shrink)