Sterilization Assembly Development Laboratory - Quality assurance program Plan

Quality control program plan for sterilization assembly development laborator

A characterization of balanced episturmian sequences

It is well known that Sturmian sequences are the aperiodic sequences that are balanced over a 2-letter alphabet. They are also characterized by their complexity: they have exactly $(n+1)$ factors of length $n$. One possible generalization of Sturmian sequences is the set of infinite sequences over a $k$-letter alphabet, $k \geq 3$, which are closed under reversal and have at most one right special factor for each length. This is the set of episturmian sequences. These are not necessarily balanced over a $k$-letter alphabet, nor are they necessarily aperiodic. In this paper, we characterize balanced episturmian sequences, periodic or not, and prove Fraenkel's conjecture for the class of episturmian sequences. This conjecture was first introduced in number theory and has remained unsolved for more than 30 years. It states that for a fixed $k> 2$, there is only one way to cover $\Z$ by $k$ Beatty sequences. The problem can be translated to combinatorics on words: for a $k$-letter alphabet, there exists only one balanced sequence up to letter permutation that has different letter frequencies

How Service-Learning Can Enhance the Pedagogy and Culture ofEngineering Programs at Institutions of Higher Education: A Review of the Literature

Many colleges and universities are actively renewing their commitment to service and to the transmission of knowledge for the public good. Students, faculty and administrators alike recognize the need to synthesize academic proficiency with responsible citizenry, in order to effectively participate in a diverse democracy. As societal needs change, disciplines change as well. The field of engineering is no exception. A competitive, diverse, global market has forced vast changes in accreditation standards, which heavily impact the university and college engineering programs that tailor instruction to meet accreditor\u27s requirements. In response to the evolving demands of industry, the field of engineering requires qualified candidates who will work collaboratively in diverse groups, excel at technical skills and can effectively communicate how their discipline impacts society. However, the current culture of engineering programs thrives on individualism, competition and male dominated discourse. Women and non-Asian minorities are severely underrepresented in the profession. In order to meet the great need for science and engineering graduates, engineering programs must adapt to find ways to recruit those populations, while also retraining and retaining its current populations (Thorn, 2001)

Paramètres gouvernant la prolifération bactérienne dans les réseaux de distribution

L'étude a permis de suivre l'évolution des caractéristiques physico-chimiques et microbiologiques des eaux dans un réseau de distribution expérimental de taille industrielle, afin de comparer d'une part l'effet du chlore et de la monochloramine sur la biomasse présente dans le système à l'équilibre et d'autre part d'établir des relations quantitatives entre prolifération bactérienne, oxydant et matière organique biodégradable.Dès les premières heures de transit dans le réseau, une consommation des oxydants est constatée, avec toutefois une plus grande stabilité de la monochloramine (vitesse de consommation de 0,05 mgCl2 l-1h-1 et 0,02 mgCl2 l-1h-1 respectivement pour le chlore et la monochloramine).Même en présence d'un désinfectant résiduel, il est possible de noter une accumulation de bactéries-à ta surface des tuyaux de distribution (105 à 106 cellules. cm-2, dont environ 1 % est cultivable sur gélose) qui augmente avec la diminution de concentration du désinfectant résiduel. Les relations logarithmiques entre densité cellulaire (phase eau ou biofilm) et oxydant résiduel montrent d'une part que pour inactiver totalement les bactéries en suspension dans l'eau il convient de maintenir une chloration en continu avec un résiduel constant supérieur ou égal à 0,5 mgCl2 l-1 et, d'autre part que les chloramines sont au moins 2,5 fois moins efficaces que le chlore, même vis-à-vis des bactéries fixées.La présence de matière organique biodégradable dans les eaux explique la prolifération des bactéries dans le système de distribution. Ainsi une concentration additionnelle de 100 µg.l-1 de carbone organique dissous biodégradable (CODB) dans l'eau entrant dans le réseau de distribution occasionne en 24 heures et à 20°C une augmentation du nombre de bactéries fixées (+7,5.105 cellules.cm-2) ou en suspension (+ 4.104 cellules.ml-1) dans le réseau de distribution, à l'équilibre, déjà largement colonisé par des micro-organismes.Ainsi le contrôle de la fraction biodégradable de la matière organique apparaît toujours comme un objectif primordial.This study was carried out in order to evaluate the variations in the physicochemical characteristics of the water in an experimental distribution system.The primary objectives of the study were :- to compare the disinfectant efficiency of chlorine and monochloramine- to establish quantitative correlations among bacterial density, concentration of residual disinfectant, and concentration of biodegradable organic matter.The finished waters were obtained from a water treatment pilot plant characterized by : prechlorination (average treatment rate : 1.4 mgCl2 l-1 and residual alter sand filtration : 0.08 mgCl2 l-1), coagulation-flocculation-sedimentation (FeCl3 treatment rate : 30 to 60 mg l-1 adjusted to the raw water turbidity below 0.3 NTU), sand filtration (filtration rate : 6 h-1) and post-disinfection with chloramine (average treatment rate : 1.8 mgCl2 l-1) or chloramine (average treatment rate : 1.66 mgCl2 l-1). The concentrations of post-disinfectant used were chosen in order to maintain chlorine at 0.2 to 0.5 mgCl2 l-1 and monochloramine at 1 mgC2 l-1 after the first 24 hours residence time in the experimental distribution system.The experimental distribution system is composed of three parallel loops connected in series (31 m length, 100 mm diameter, cement lined cast iron, water velocity : 1m s-1). The configuration and operation of the system permitted a residence time of 24 hours in each loop (that is 72 hours for the whole system). Appropriate sample tap locations facilitated removal of bulk water samples. Special sampling parts also permitted sampling of cement coupons for determination of attached biofilm.The measured parameters were : residual oxidant (DPD method), DOC, BDOC (28 days of incubation at 28 °C with a bacterial inoculum), cell density in the bulk water phase (CFU ml-1) and in the biofilm (CFU cm-2) after 15 days of incubation at 20-22 °C. Total cells were enumerated using the epifluorescence direct count technique.For each experiment, all the sampling sequences were carried out on each of three days, after quasi steady-state was achieved in the system (4 to 6 weeks after starting each experiment). The data were analysed in order to characterize the treated and distributed waters; the results discussed here are based on the averages of the measured parameters tram the water samples and biofilm samples taken after the system achieved quasi steady-state.Characteristics of the treated watersThe treated waters were characterized by important variations at the DOC, BDOC and cell density. For example, the concentrations of DOC showed a seasonal variation ranging from 0.8 to 1.3 mg Cl-1 in winter to 1.6 to 2.6 mg Cl-1 in summer.The treated waters contained approximately the same concentrations of residual disinfectant, averaging 1.6 mgCl2 l-1 for chlorine and 1.5 mgCl2 l-1 for monochloramine.However, a significant difference cell density was found between the two post-disinfectants. Cell densities by the epifluorescence direct count technic were 1.6 x 103 ml-1 (0.3 % of CFU ml-1) with chlorine and 6.3 x 104 ml-1 (0.03 % of CFU ml-1) with monochloramine. The difference on cell density between the post-chlorination and the post-chloramination treatments has been observed systematically, and may be explained either as cellular lysis with chlorine or an interference when using epifluorescence counting for chlorinated waters.Characteristics of the distributed watersWhatever the season, depletion of oxidant (chlorine or monochloramine), and elimination of dissolved organic matter (DOC, BDOC) occured during the first hours of circulation of water in the distribution system. The net result was an increase in bacterial cell density.During the first hours of circulation of the waters in the distribution system, depletion of the disinfectant occured. Depletion was more rapid for chlorine (-0.05 mgCl2 l-1 h-1) titan for monochloramine (-0.02 mgCl2 l-1 h-1), winch is considered more stable titan chlorine.Even in the presence of a residual disinfectant in the distribution system, microorganisms are present in the water phase (104 to 106 cells ml-1 by epifluorescence direct count; 1 % CFU ml-1 after 15 days of incubation at 20-22 °C) and in the biofilm (105 to 106 cells cm-2 by epifluorescence direct count; 1 % CFU ml-1 after 15 days of incubation at 20-22 °C). The bacterial density increased white the disinfectant residual decreased. The apparent growth rate of the attached biomass (µfix) in loop 2 of the chlorinated distribution system (equivalent to 48 hours detention), was close to the µfix calculated for loop 2 of the chloraminated distribution system : the values were 0.0043 h-1 and 0.005 h-1 respectively.In addition, the change in the organic matter (expressed as DOC) occured in two steps :- a slight increase in DOC during the 24 first hours of residence time (loop 1), when increased residual disinfectant were present.- a bacterial consumption of DOC after 24 hours of residence time (loops 2 and 3), even in the presence of small concentrations of disinfectants.In loop 2 (48 hours residence time of the water in the system; chlorine : 0.01 mgCl2 l-1, chloramine : 0.3 mgCl2 l-1 h-1), the rates of DOC elimination averaged 13 mgCl2 l-1 h-1 and 0.42, mgCl2 l-1 h-1, respectively in the chlorinated and chloraminated distribution systems. This decrease in DOC concentrations was related to the increase in bacterial density.Relationships between cell density, oxidant and organic matterLinear relationships between the concentration of residual oxidant (chlorine or monochloramine) and the cell density in the water phase or in the biofilm show that :- whichever oxidant was used, the pipe loop sections without residual disinfectants were characterized by about 5 x 106 attached cells per cm2 (4 to 10% were able to grow on agar medium in 15 days at 20-22 °C) and by 4 x 105 planktonic cells per ml (1 % CFU ml-1);- consistently, in the sections of the system with a residual disinfectant, the bacteria (CFU and epilluorescence counting) in the water phase were more sensitive to the residual disinfectant (chlorine or monochloramine) than the bacteria attached to the pipe walls (biofilm).However, there was a difference in effectiveness between the two disinfectants; chlorine was more efficient in controlling planktonic bacteria and biofilm bacteria than was monochloramine.For example, to achieve complete inactivation of the planktonic bacteria (CFU ml-1) a constant chlorine residual of 0.5 mgCl2 l-1 was required throughout the whole distribution system, compared to 2.5 times more chloramine to achieve the same efficiency.Finally, with equivalent concentrations of residual disinfectant, the microbiological quality of the chlorinated distribution waters was better than that of the chloraminated distribution waters.From loop to loop, linear relationships between ∆DOC and cell density pointed out that the presence of biodegradable organic matter can explain the bacterial proliferation in the distribution system. For example, a concentration of BDOC as low as 0.1 mgC l-1 resulted in an increase in the cell density : an additional accumulation of 7.5 x 105 attached cells cm-2 and 4 x 104 planktonic cells ml-1 was observed in the experimental distribution system at quasi steady-state.Consequently, the control of the biodegradable organic carbon remains one of the prime objectives in order to achieve biologically stable distribution waters

Sustainable enterprises: Addressing management challenges in the 21st Century

Our world in the 21st Century is one of a “crisis society”. That is, we have reached a state where most of our major systems – economic, environmental, social – in are crisis and in need of restructuring. We can see this play out in the global financial, climate, social and identity crises we face. The underlying causes of these crises are our current systems of production and consumption. We suggest the solution lies in moving beyond addressing the crises individually and symptomatically towards developing sustainable enterprises, sustainable communities and sustainable lifestyles. From these perspectives, we can begin understand better the interrelationships creating this crisis society and more holistically address and repair the damage we done to the Earth and ourselves. We conclude by identifying areas of future research needed to facilitate this movement towards a sustainable society

Life as a Parkland Pathways Student

This podcast is the result of an ethnography assignment for Anthropology 103 at Parkland College in Champaign, IL. Students interviewed other students involved with Parkland Pathways, a competitive program that guarantees admission to the University of Illinois through Parkland College transfer credits. Four students were interviewed to discover their likes and dislikes of the program

Organizational dynamics in industrial ecosystems: Insights from organizational theory

This chapter presents three important and inter-related perspectives in organizational theory - institutional theory, field theory, and social network theory – that together shed light on the organizational dynamics inherent in and critical to the development of industrial ecosystems. Within the social science literature, these theories provide a language and set of conceptual tools for holistically analyzing the formal and informal influences of the broader social environment on a company, its possible actions within this environment, and associated outcomes. Such an understanding also sheds light on the constraints and opportunities that individual decision makers face and enables a better understanding of agents’ behavior, whether that of individuals or organizations, in bringing about the changes that industrial ecology demands

Facilitating regional industrial symbiosis: Network growth in the UK’s National Industrial Symbiosis Programme

In the years since the discovery of Kalundborg’s long-lived network of resource exchanges, industrial symbiosis, and its potential for reducing the environmental impact of industrial activity on a local or regional scale, has been the subject of intense interest. Industrial symbiosis is defined as the enlistment of geographically proximate facilities in the “physical exchange of materials, energy, water, and by-products” (Chertow, 2000: 314). While some industrial symbiosis occurs between firms that are closely co-located, such as those in the same industrial park (see Chapters 4 and 6), other efforts to develop industrial symbiosis are undertaken on regional geographic scales. This chapter considers regional-scale industrial symbiosis, and, in particular, the development of a network of industrial symbiosis facilitated by a single brokering organization