Positive Feedback

Over the last century, large-scale water development of the upper Rio Grande in the U.S. and Mexico, and of the Rio Conchos in Mexico, has resulted in progressive channel narrowing of the lower Rio Grande in the Big Bend region. We used methods operating at multiple spatial and temporal scales to analyze the rate, magnitude, and processes responsible for channel narrowing. These methods included: hydrologic analysis of historic stream gage data, analysis of notes of measured discharges, historic oblique and aerial photograph analysis, and stratigraphic and dendrogeomorphic analysis of inset floodplain deposits. Our analyses indicate that frequent large floods between 1900 and the mid-1940s acted as a negative feedback mechanism and maintained a wide, sandy, multi-threaded river. Declines in mean and peak flow in the mid-1940s resulted in progressive channel narrowing. Channel narrowing has been temporarily interrupted by occasional large floods that widened the channel, however, channel narrowing has always resumed. After large floods in 1990 and 1991, the active channel width of the lower Rio Grande has narrowed by 36-52%. Narrowing has occurred by the vertical accretion of fine-grained deposits on top of sand and gravel bars, inset within natural levees. Channel narrowing by vertical accretion occurred simultaneously with a rapid invasion of non-native riparian vegetation (Tamarix spp., Arundo donax) which created a positive feedback and exacerbated the processes of channel narrowing and vertical accretion. In two floodplain trenches, we measured 2.75 and 3.5 m of vertical accretion between 1993 and 2008. In some localities, nearly 90% of bare, active channel bars were converted to vegetated floodplain during the same period. Upward shifts of stage-discharge relations occurred resulting in over-bank flooding at lower discharges, and continued vertical accretion despite a progressive reduction in stream flow. Thus, although the magnitude of the average annual flood was reduced between 40 and 50%, over-bank flooding continued. These changes reflect a shift in the geomorphic nature of the Rio Grande from a wide, laterally unstable, multi-thread river, to a laterally stable, single-thread channel with cohesive, vertical banks, and few active in-channel bars.

In this paper a novel rail-to-rail fully differential operational transconductance amplifier (OTA) working at low- supply voltages (1.5 V) with reduced consumption and showing high DC gain is presented. An adaptive biasing circuit allows to obtain low stand-by power dissipation (lower than 0.19 mW in the rail-to-rail version), while the high DC gain (over 80 dB) is ensured by a positive feedback. The circuit, designed in a standard CMOS integrated technology (AMS 0.35 mum), has a 40 V/mus slew-rate for a capacitive load of 15 pF. The calculated values of two quality factors, named FOMS/L, in the literature, show the validity of the proposed OTA.

In the network economy a profitability analysis based on the figures of one company is not sufficient to obtain an insight into the competitiveness of the whole network. In this paper, the applicability of the consolidated financial statement as a tool for managing network profitability is analyzed. The idea of the consolidated network is presented on the basis of a conceptual analysis, derived from an action research in two company networks. Despite the fact that there are a number of barriers on the way of the consolidated network, the idea of a consolidated view on business has received a positive feedback. The recognized benefits include value creation, profit calculation and profit sharing, and some other ways to improve performance within the network. Using the consolidated network as a metaphor is a way to communicate in supply chains.

We examine the correlations between the national IQs of Lynn and Vanhanen . IQ and the wealth of nations. Westport, CT: Praeger. Westport, CT: Praeger, Lynn, R. and . IQ and global inequality. Athens, GA: Washington Summit Books.) and educational attainment scores in math and science for 10-and 14-year olds in 25 countries and 46 countries (respectively) given in the TIMSS 2003 reports. It was found that national IQs had (attenuation corrected) correlations of between 0.92 and 1.00 with scores in math and science. The results are interpreted as a validation of the national IQs. They suggest that national differences in educational attainment may be attributable to differences in IQ, or alternatively that national IQs and in educational attainment are both indicators of the mental ability of national populations. It is also shown that national IQs are positively associated with national per capita income (r = .61). It is proposed that these have a reciprocal positive feedback relationship such that each augments the other.

Caregiver interactions with young autistic children were contrasted with those involving caregivers and developmentally matched mentally retarded and normal infants. Caregivers of autistic children were similar to other caregivers in their responsiveness to child nonverbal communication bids and in their engagement in mutually sustained play. Caregivers of autistic children were similar to caregivers of mentally retarded children in their greater

Microbial activity in semiarid and arid environments is closely related to the timing, intensity, and amount of precipitation. The characteristics of the soil surface, especially the influence of biological soil crusts, can determine the amount, location, and timing of water infiltration into desert soils, which, in turn, determines the type and size of microbial response. Nutrients resulting from this pulse then create a positive feedback as increases in microbial and plant biomass enhance future resource capture or, alternatively, may be lost to the atmosphere, deeper soils, or downslope patches. When rainfall intensity overwhelms the water infiltration capacity of the plant interspace or the plant patch, overland water flow links otherwise separated patches at many different scales via the transport of nutrients in water, soil, and organic matter. For example, material carried from the plant interspace is often deposited under an adjacent plant. Alternatively, material from both of these patches may be carried to rills that feed ephemeral channels, thence to seasonally intermittent and, finally, perennial streams. These inputs can either be retained by the stream-riparian ecosystem or be exported in surface flow. However, in larger perennial streams, the fate of these material inputs is confounded by the impact of storm-driven flows on the extant aquatic biota, as flash floods can also represent succession-initiating disturbances to the stream-riparian ecosystem on a wide range of time scales. In contrast to uplands where precipitation initiates the microbial response, nutrient transfers can support a flush of plant uptake and microbial processing, triggered by high nutrient concentrations and changed nutrient form (e.g., nitrate or ammonium). The nature and strength of the linkages between the different ecosystem components define the structure and function of arid ecosystems. Losses of materials are natural processes, but it is problematic when ''conserving'' systems become ''leaky'' via anthropogenic disturbance and losses exceed gains.

Past research has investigated age differences in frontal-based decision making, but few studies have focused on the behavioral effects of striatal-based changes in healthy aging. Feedback learning has been found to vary with dopamine levels; increases in dopamine facilitate learning from positive feedback, whereas decreases facilitate learning from negative feedback. Given previous evidence of striatal dopamine depletion in healthy aging, we investigated behavioral differences between collegeaged and healthy older adults using a feedback learning task that is sensitive to both frontal and striatal processes. Method: Seventeen college-aged (M ϭ 18.9 years) and 24 healthy, older adults (M ϭ 70.3 years) completed the Probabilistic Selection task, in which participants are trained on probabilistic stimulus-outcome information and then tested to determine whether they learned more from positive or negative feedback. Results: As a group, the older adults learned equally well from positive and negative feedback, whereas the college-aged group learned more from positive than negative feedback, F(1, 39) ϭ 4.10, p Ͻ .05, r effect ϭ .3. However, these group differences were not due to older individuals being more balanced learners. Most individuals of both ages were balanced learners, but while all of the remaining young learners had a positive bias, the remaining older learners were split between those with positive and negative learning biases (2 (2) ϭ 6.12, p Ͻ .047). Conclusions: These behavioral results are consistent with the dopamine theory of striatal aging, and suggest there might be adult age differences in the kinds of information people use when faced with a current choice.

The vegetation of the Wet Tropics bioregion of Far North Queensland is a complex system whose components (mainly tropical rainforests and fire-prone forests and woodlands) have mostly been studied independently from each other. We suggest that many characteristics of the vegetation are consistent with those of a complex, dynamic, spatially heterogeneous system which exhibits alternative stable states. We propose these states are driven and maintained by the interaction of vegetation-specific positive feedback loops with the regions’ environmental parameters (such as topography, steep humidity gradients and seasonality) and result in the rainforest/fire-prone vegetation mosaic that characterises the area. Given the regions’ magnitude, biodiversity and complexity, we propose the Wet Tropics as an important new example and a good testing ground for alternative stable state and resilience theories in large heterogeneous natural systems. At the same time, thinking in terms of alternative stable states and resilience creates a new context for understanding the regions’ biological dynamics.

Anthropogenic greenhouse gases are expected to induce changes in global climate that can alter ecosystems in ways that, in turn, may further affect climate. Such climate-ecosystem interactions can generate either positive or negative feedbacks to the climate system, thereby either enhancing or diminishing the magnitude of global climate change. Important terrestrial feedback mechanisms include CO 2 fertilization (negative feedbacks), carbon storage in vegetation and soils (positive and negative feedbacks), vegetation albedo (positive feedbacks), and peatland methane emissions (positive and negative feedbacks). While the processes involved are complex, not readily quantifiable, and demonstrate both positive and negative feedback potential, we conclude that the combined effect of the feedback mechanisms reviewed here will likely amplify climate change relative to current projections that have not yet adequately incorporated these mechanisms.

Objective: To explore approaches for integrating and visualizing time-oriented medication data in narrative and structured formats and to address related issues on handling temporal abstraction, granularity, and uncertainty. The ultimate goal is to improve medication reconciliation by providing clinicians with more accurate medication information in patient care. Methods: An event taxonomy was generated to capture different combinations of clinical and temporal uncertainties. A prototype of a temporal visualization system was implemented using an open source software package called Timeline. Medications were parsed and mapped to the event taxonomy, and then represented in Timelines. Seventy-five medications from narrative discharge summary reports and seventy-nine medications from structured orders were used as data input for temporal visualization. Five physicians served as domain experts and answered ten proof-of-concept survey questions. Results: Overall positive feedback from experts suggested the potential value of the proposed timeline visualization method. Challenges were also identified, and future work will include reconciliation of medications from various sources based on temporal attributes and medication classification.

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Measurements of air volatile organic compounds (VOCs) and ozone concentrations in dierent rural sites of Catalonia (NE Spain) were conducted during 1995 and 1996, and the eects of ozone concentrations on biogenic emissions of Mediterranean plants were studied in open top chambers. A signi®cant positive relationship was found between tropospheric ozone and VOC concentrations, which followed seasonal (maximum in early summer and minimum in early winter) and geographical (slightly larger concentrations in interior than in coastal sites) patterns. Results in the open top chambers fumigation experiments showed species-speci®c responses. There was no signi®cant eect of ozone on VOCs and terpene emission by Aleppo pines, Pinus halepensis L., but there was an order of magnitude increase in VOC emission with increasing tropospheric ozone concentrations (plus 40 nl L À1) in tomatoes, Solanum lycopersicum L. var. Tiny Tim. This response of tomato plants thus opens the possibility of a positive feedback for tropospheric ozone formation.

Multi-proxy approach was used to reconstruct the environmental conditions of remote lakes in the High Tatra Mountains (Slovakia) over the past few centuries (approximately 500-1000 years). Short sediment cores (*30 cm) taken from three morphologically similar glacial lakes distributed along altitudinal gradient (subalpine to alpine conditions) were analysed for organic matter content (LOI), diatoms and chironomids. Both descriptive and correlative approaches were used for analysing stratigraphical data. Predictive canonical correspondence analysis and co-correspondence analysis were applied to directly relate physical and biological proxies to each other. The relationship between LOI and biotic proxies was inconsistent across groups and lakes. Concordant patterns in diatom and chironomid composition were found in two non-acidified lakes. Common trends in those assemblages indicated major past environmental events such as the Little Ice Age, air pollution and lake acidification. In contrast, no relationship between the composition of diatom and chironomid assemblages was found in the formerly acidified lake, suggesting different responses of assemblages to acidification. While chironomids showed shifts that are attributable to recovery, diatoms assemblage remained relatively stable throughout the uppermost layers of the sediment record. On the other hand, climatic-driven changes in assemblages detected in the deeper layers were more pronounced in diatoms than in chironomids.

In much of the current literature on supply chain management, supply networks are recognized as a system. In this paper, we take this observation to the next level by arguing the need to recognize supply networks as a complex adaptive system (CAS). We propose that many supply networks emerge rather than result from purposeful design by a singular entity. Most supply chain management literature emphasizes negative feedback for purposes of control; however, the emergent patterns in a supply network can much better be managed through positive feedback, which allows for autonomous action. Imposing too much control detracts from innovation and flexibility; conversely, allowing too much emergence can undermine managerial predictability and work routines. Therefore, when managing supply networks, managers must appropriately balance how much to control and how much to let emerge.

1] Marine sediments recorded a series of Heinrich events during the last glacial period, massive ice surges that deposited prominent layers of ice-rafted debris in the North Atlantic. Here we explore oceanic mechanisms that can potentially trigger and amplify the observed ice calving events. Simulations of abrupt glacial climate change with a coupled ocean-atmosphere-sea ice model show a substantial regional sea level rise in the North Atlantic in response to a collapse of the Atlantic meridional overturning circulation (MOC). The increased heat uptake of the global ocean after the MOC collapse leads to an additional rise in global sea level. We hypothesize that these sea level changes have the potential to destabilize Northern Hemisphere ice shelves and ice sheets and to trigger ice surges. Sea level rise due to ice calving and subsurface ocean warming provides two positive feedback mechanisms contributing to further destabilization of ice shelves and ice sheets.

This study explored the potential uses of feedback systems in the trucking industry as a means of improving safety. Since truck drivers spend a majority of their working time alone and do not interact with peers, it may be possible to use data gathered by in-vehicle technology to provide feedback to drivers about their driving behavior. The purpose of this study was to examine truck driversÕ attitudes toward using in-vehicle technology to provide feedback for enhancing driving safety and to understand the best ways of providing feedback to truck drivers. Nine focus groups were conducted, with a total of 66 participants, to collect qualitative data on attitudes toward technology and feedback. The focus group results were used to develop a questionnaire. Survey data were then collected from 198 long-haul truck drivers to provide quantitative information. Truck drivers reported that they would like to receive more feedback and that positive feedback was preferred over negative feedback. Feedback from truck driversÕ supervisors or managers was more desired than feedback from technology. However, most drivers were willing to accept feedback by technology if the program was designed properly. The truck drivers expressed no strong preference regarding the best form of feedback by technology on driving performance (i.e., modality, frequency and timing). Therefore it is important for a program which uses technology for providing feedback to be adaptable to different driversÕ preferences.

Patients with a chronic cough have asthma or "asthma-related" diagnoses such as cough variant asthma or non-asthmatic eosinophilic bronchitis usually responsive to inhaled corticosteroid therapy, or nonasthma-related diagnoses including "idiopathic" or "unexplained" cases. Both of these conditions involve airway inflammation. More recently, structural changes or remodeling of the lower airways, which have been considered characteristic of classic asthma with wheezing, have also been demonstrated in patients with chronic cough, irrespective of its cause. In this article, the presence, pathogenesis, and possible consequences of such structural changes in patients with chronic cough are reviewed. Although whether chronic cough leads to structural changes or structural changes is a cause of chronic cough is difficult to determine, the concomitance of both mechanisms may lead to a positive feedback mechanism or a vicious cycle of cough persistence.

A flow visualisation study was performed to investigate a periodic flow instability in a bifurcating duct within the tip of the flares at the Shell refinery in Clyde, NSW, to verify the trigger of a combustion-driven oscillation proposed in Part A of this study, and to identify its features. The model study assessed only the flow instability, uncoupled from the

IP protection of hardware designs is the most important requirement for many FPGA IP vendors. To this end, various solutions have been proposed by FPGA manufacturers based on the idea of bitstream encryption. An alternative solution was advocated in [18]. Simpson and Schaumont proposed in [18] a new approach based on Physical Unclonable Functions (PUFs) for IP protection on FPGAs. PUFs are a unique class of physical systems that extract secrets from complex physical characteristics of the integrated circuits which along with the properties of unclonability provide a highly secure means of generating volatile secret keys for cryptographic operations. However, the first practical PUF on an FPGA was proposed only later in [7] based on the startup values of embedded SRAM memories which are intrinsic in some of the current FPGAs. The disadvantage of these intrinsic SRAM PUFs is that not all FPGAs support uninitialized SRAM memory. In this paper, we propose a new PUF structure called the Butterfly PUF that can be used on all types of FPGAs. We also present experimental results showing their identification and key generation capabilities.

Spam and noisy ratings affect the performance of recommendation systems which can lead to incorrect estimations and predictions. The challenge is to discover noisy ratings early in order to isolate its impact. In this paper we suggest an analysis using positive feedback which considers the user's level of confidence, and grades the user from completely honest to complete dishonest. The calculated user's level of confidence is computed based upon the detected level of honesty and affect his ratings. Each domain of ontologies has a calculated region of rejection and non-rejection using each user confidence level, placing his ratings in one region or another and thereby affecting his level of confidence. We used a Movie Lens of 1M ratings dataset to perform the required training. Suggested method has distinguished perfectly between Normal, Excess, Inferiority, and completely dishonest.

In two studies, we examined inter-individual variability in responses to both negative and positive events. In the first study, participants (119 college students) reported on negative and positive events from their own lives. The second was an experiment in which participants (133 college students) were given either negative or positive feedback about their personality. With negative events, more insecure individuals, especially anxiously attached, evidenced more intense negative emotional reactions and greater processing of (i.e., ruminating on) negative experiences. With positive events, securely attached individuals and less anxiously attached engaged in greater processing of positive experiences (maximized), whereas more insecure individuals tended to minimize positive experiences. Gender differences for emotion regulation were moderated by either attachment or event type. Findings for negative events generally coincide with prior research, and those for positive events provide...

Significant increases in atmospheric carbon dioxide are occurring as a result of fossil fuel combustion. More than a four-fold increase over preindustrial levels may occur by the year 2100. Heating of the atmosphere, changes in precipitation patterns and global storm paths, and other resulting effects are sure to cause significant social changes. This article is essentially a methodological case study demonstrating a useful but inexpensive type of technology assessment. It summarizes current research findings on "the CO? effect," and presents hitherto unpublished findings that resulted from a brief but systems-oriented approach. These findings suggest that most published forecasts of phenomena associated with a CO? buildup may be systematically low because various positive feedback relationships are not reflected. Technology assessment (TA) is an increasingly important approach to futuresoriented policy analysis and planning. It is based on the assumption that technology (broadly interpreted) can and should be subjected to social controls for purposes of achieving societal objectives. In its complete form, the TA involves: l describing and forecasting plausible technological developments l identifying and assessing their impacts l analyzing the relevant policy options available to decision makers In general, an assessment may have numerous consequences, some of which include: l support for a technological development l stimulation of relevant research in scientific, technological, or social policy areas *This article (and a complementary paper emphasizing the substantive results of the study reported in this methodological paper) were supported by the U.S. Department of Energy, under Contract No. 80EV10021.

This research examined whether Whites favourably bias their feedback to minorities in order to see themselves as egalitarian. White teacher trainees first had their egalitarian self-images affirmed, left unchanged, or threatened. They then provided feedback on a poorly written essay supposedly authored by either a Black or a White student. As predicted, trainees in the Black writer/self-image threat condition selectively rated essay content more favourably, recommended less time for skill development, provided more favourable copy-editing comments, and generated more equivocating 'buffers'. In contrast, trainees in the Black writer/self-image boost condition supplied feedback indistinguishable from feedback provided by trainees in the White writer conditions, which was unaffected by the self-image conditions. The implications for minority education and intergroup communication are discussed.

Purposes of this study were to identify the leadership style of coaches, player satisfaction and relationship between leadership style of the coaches and player satisfaction. This study comprises of 101 basketball players in Malaysian Intervarsity Championship. This study was conducted during the competition season. A descriptive study is used in carrying out this research. Two instruments, revised version Leadership Scale for Sport (RLSS) by and Athlete Satisfaction Questionnaire (ASQ) by were used to examined style of coaching behaviors which university football players preferred and their satisfaction in football team. The data was analyzed using Statistical Package for Social Science (SPSS) The descriptive analysis of the data were analyzed using by means, frequencies, percentage, and standard deviations for each item were found for males, females and each level of sport involvement. For the purpose of correlation, Pearson's was used. Correlation was done with leadership style against athlete satisfaction. The level of significance was set at p < 0.05. Athletes were more preferred training and instruction coaching behavior which the highest mean score (M = 3.01, SD = .82) and followed by positive feedback coaching behavior (M = 2.94, SD = .85), social consideration coaching behavior (M = 2.87, SD = .86), social support coaching behavior (M = 2.61, SD = .90), democratic coaching behavior (M = 2.37, SD =.92) and © Research Journal of Internatıonal Studıes -Issue 9 (January, 2009) 5

Sustainable energy technologies develop within the context of systems made up by networks of actors, institutions and (related) technologies. These Tech nological Innovation Systems (TISs) do not come into existence overnight but are the result of a bu ild-up process. This paper provides insights that support a better understanding of this build-up pro cess for TISs in an early development stage, the so - called formative stage. The process of TIS build-up is conceptualised in te rms of seven system functions. The system functions are types of activities necessary for a TIS to deve lop and to support innovation. The main contributio n of this paper is to study the phenomenon of cumulat ive causation, i.e. the idea that TIS build-up may accelerate due to positive feedback loops of system functions that interact over time. Such feedback mechanisms or &#39;motors of sustainable innovation&#39;, m ay contribute to the strategic knowledge on emerging sustainable energy technologies. Base...

Collection of marine invertebrates for use as fishing bait is a substantial activity in many parts of the world, often with unknown ecological consequences. As new fisheries develop, it is critical for environmental managers to have high quality ecological information regarding the potential impacts, in order to develop sound management strategies. Crab-tiling is a largely unregulated and un-researched fishery, which operates commercially in the south-west UK. The target species is the green crab Carcinus maenas. Those crabs which are pre-ecdysis and have a carapace width greater than 40 mm are collected to be sold to recreational anglers as bait. Collection involves laying artificial structures on intertidal sandflats and mudflats in estuaries. Crabs use these structures as refugia and are collected during low tide. However, the effect that this fishery has on populations of C. maenas is not known. The impact of crab-tiling on C. maenas population structure was determined by sampling crabs from tiled estuaries and non-tiled estuaries using baited drop-nets. A spatially and temporarily replicated, balanced design was used to compare crab abundance, sizes and sex ratios between estuaries. Typically, fisheries are associated with a reduction in the abundance of the target species. Crab-tiling, however, significantly increased C. maenas abundance. This was thought to be a result of the extra habitat in tiled estuaries, which probably provides protection from natural predators, such as birds and fish. Although crabs were more abundant in tiled estuaries than non-tiled estuaries, the overall percentage of reproductively active crabs in non-tiled estuaries was greater than in tiled estuaries. As with most exploited fisheries stocks, crabs in exploited (tiled) estuaries tended to be smaller, with a modal carapace width of 20-29 mm rather than 30-39 mm in non-tiled estuaries. The sex ratio of crabs however; was not significantly different between tiled and non-tiled estuaries. These results illustrate the potential to manage fished populations using habitat provision to mitigate the effects of fishing pressure.

Analysis of high speed CMOS current comparator is presented with low input impedance using a simple biasing method. The simulation results from PSPICE demonstrate the propagation delay at low input currents at supply voltages of 1.8v, 2v, 2. 2v and stability analysis using 0.25um CMOS technology. So it is suitable to high speed applications.

ABSTRACT Islanding detection is an essential function for safety and reliability in grid-connected distributed generation (DG) systems. Several methods for islanding detection are proposed in literature, but most of them may fail in multi-source configurations, or they may produce important power quality degradation when the DG penetration is high. This paper presents theoretical analysis and evaluation of an active anti-islanding protection algorithm for Voltage Source Inverter (VSI) multi-source DG systems proposed in previous work. Particularly, this paper presents an evaluation of the anti-islanding scheme considering: different multi-inverter topologies, the effect of transmission line length and the effect of the measured variations of utility voltage.

Three studies asked why people sometimes seek positive feedback (self-enhance) and sometimes seek subjectively accurate feedback (self-verify). Consistent with self-enhancement theory, people with low self-esteem as well as those with high self-esteem indicated that they preferred feedback pertaining to their positive rather than negative self-views. Consistent with self-verification theory, the very people who sought favorable feedback pertaining to their positive self-conceptions sought unfavorable feedback pertaining to their negative self-views, regardless of their level of global self-esteem. Apparently, although all people prefer to seek feedback regarding their positive self-views, when they seek feedback regarding their negative self-views, they seek unfavorable feedback. Whether people self-enhance or self-verify thus seems to be determined by the positivity of the relevant self-conceptions rather than their level of self-esteem or the type of person they are.

Based on self-determination theory , an experimental study with middle school students participating in a physical education task and a correlational study with highly talented sport students investigated the motivating role of positive competence feedback on participants' well-being, performance, and intention to participate. In Study 1, structural equation modeling favored the hypothesized motivational model, in which, after controlling for pretask perceived competence and competence valuation, feedback positively predicted competence satisfaction, which in turn predicted higher levels of vitality and greater intentions to participate, through the mediation of autonomous motivation. No effects on performance were found. Study 2 further showed that autonomous motivation mediated the relation between competence satisfaction and well-being, whereas amotivation mediated the negative relation between competence satisfaction and ill-being and rated performance. The discussion focuses on the motivational role of competence feedback in sports and physical education settings.

Fishing at the early stage of fisheries development most probably approximated natural predation. Nowadays, fishing approximates ''extermination'' with dramatic effects on aquatic ecosystems. Conventional fisheries models and management practices are inadequate to handle the present situation because, among many other factors, fishing: (a) drives fish stocks to exhibit smaller body sizes and age/length at maturity (i.e., ''tropicalization'') and (b) increases catch variability, thus increasing uncertainty. The realization of (a) and (b) renders conventional practices even more inadequate, thus producing a never-ending positive feedback loop. Although the application of the precautionary approach to fisheries management together with the development of indicators and reference point values that trigger management actions seem to be an important step forward, their adoption within the framework of the same conventional models used to assess fish stocks could introduce another degree of complexity into existing models. With Ockham's razor as a primary guiding principle, the advantage of using ever more complex models is suspect. Ecosystem management seems the only alternative. Within this framework, alternative simpler ''models and strategies'' such as large-scale marine protected areas, in which no fishing takes place, are available and promising, and their adoption as a primary management tool satisfies simultaneously all objectives that have been set for ecosystem management.

Multi-proxy approach was used to reconstruct the environmental conditions of remote lakes in the High Tatra Mountains (Slovakia) over the past few centuries (approximately 500-1000 years). Short sediment cores (*30 cm) taken from three morphologically similar glacial lakes distributed along altitudinal gradient (subalpine to alpine conditions) were analysed for organic matter content (LOI), diatoms and chironomids. Both descriptive and correlative approaches were used for analysing stratigraphical data. Predictive canonical correspondence analysis and co-correspondence analysis were applied to directly relate physical and biological proxies to each other. The relationship between LOI and biotic proxies was inconsistent across groups and lakes. Concordant patterns in diatom and chironomid composition were found in two non-acidified lakes. Common trends in those assemblages indicated major past environmental events such as the Little Ice Age, air pollution and lake acidification. In contrast, no relationship between the composition of diatom and chironomid assemblages was found in the formerly acidified lake, suggesting different responses of assemblages to acidification. While chironomids showed shifts that are attributable to recovery, diatoms assemblage remained relatively stable throughout the uppermost layers of the sediment record. On the other hand, climatic-driven changes in assemblages detected in the deeper layers were more pronounced in diatoms than in chironomids.

The planet Mars, while cold and arid today, once possessed a warm and wet climate, as evidenced by extensive fluvial features observable on its surface. It is believed that the warm climate of the primitive Mars was created by a strong greenhouse effect caused by a thick CO 2 atmosphere. Mars lost its warm climate when most of the available volatile CO 2 was fixed into the form of carbonate rock due to the action of cycling water. It is believed, however, that sufficient CO 2 to form a 300 to 600 mb atmosphere may still exist in volatile form, either adsorbed into the regolith or frozen out at the south pole. This CO 2 may be released by planetary warming, and as the CO 2 atmosphere thickens, positive feedback is produced which can accelerate the warming trend. Thus it is conceivable, that by taking advantage of the positive feedback inherent in Mars' atmosphere/regolith CO 2 system, that engineering efforts can produce drastic changes in climate and pressure on a planetary scale.

Emotional intelligence is the ability to monitor one's own and others' thinking and actions. In this integrative review, the author seeks to determine the causes of the weak relationship between emotional intelligence and performance by positing that certain emotional competencies, rather than emotional intelligence, are the true predictors of performance. The author theorizes that emotional competencies (including self-control, resilience, social skills, conscientiousness, reliability, integrity, and motivation) interact with organizational climate and job demands or job autonomy to influence performance, as represented in the form of 5 empirically testable propositions. Self-control and emotional resilience are considered to delay the onset of a decline in performance from excessive job demands. Social skills, conscientiousness, reliability, and integrity assist to promote trust, which in turn may build cohesiveness among the members of work groups. Motivation may fuel job involvement in environments that promise psychological safety and psychological meaningfulness. A combination of superior social skills and conscientiousness may enhance the self-sacrifice of benevolent employees to heightened levels of dependability and consideration. Finally, emotional honesty, self-confidence, and emotional resilience can promote superior performance, if positive feedback is delivered in an informative manner, and can mitigate the adverse effects of negative feedback.

Hybrid learning, or blended learning, has become an interesting learning delivery method in recent years. Many universities have sought to develop their own hybrid learning courses as another option for students and instructors who prefer to replace some portion of traditional face-to-face meeting time with online instruction. This paper provides some pragmatic guidance for establishing hybrid learning courses in universities. The authors focus on the use of information technology, as well as the development and the design of the course content. The paper also illustrates a case study of hybrid learning courses at NJIT. The research results showed no significant difference between the performance of the students who took a course in hybrid mode versus the performance of those who took the identical course in distance learning mode. Some positive feedback in terms of perceived benefit from the hybrid course instruction and course materials was obtained from the students. The student learning styles were also investigated. The results demonstrated that the majority of students who participated in the hybrid learning course are active/sensing/sequential/visual learners. Most of them preferred visual presentations to verbal explanations. The research results also revealed the difference between learning styles of students with high performance, and those with low performance.