Energy and material refineries of future: Wastewater treatment plants.

There have been many important milestones on humanity's long journey towards achieving environmental sanitation. In particular, the development of the activated sludge system can be claimed to be one of the most groundbreaking advances in the protection of both public health and the wider ecosystem. The first wastewater treatment plants (WWTPs) were developed over a century ago and were soon configured for use with activated sludge. However, despite their long history and service, conventional activated sludge (CAS) plants have become an unsustainable method of wastewater treatment. In addition, conventional WWTPs are intensive energy-consumers and at best allow only very limited material recovery. A paradigm shift to convert existing WWTPs into more sustainable facilities must therefore be considered necessary and to this end the wastewater biorefinery (WWBR) concept may be considered a solution that maximizes both energy and material recovery, in line with the circular economy approach.

Comparison of High Hip Center versus Anatomical Reconstruction Technique in Crowe Types II and III Developmental Dysplasia of the Hip: a Retrospective Clinical Study.

PURPOSE OF THE STUDY The literature is conflicting as to whether the high hip center (HHC) reconstruction in total hip arthroplasty (THA) is an ideal option for patients with severe developmental dysplasia of the hip (DDH). This study aimed to compare the mid-term functional and radiographic outcomes of THA using HHC versus anatomical hip center (AHC) technique in Crowe types II and III DDH. Our hypothesis was that there may be no differences in terms of functional and radiographic outcomes between patients who underwent THA using HHC or AHC. MATERIAL AND METHODS Fifty-seven patients who underwent a primary THA due to Crowe type-II or type-III DDH were retrospectively reviewed and included. Patients were divided into two groups as per the hip center reconstruction: Group A (AHC technique) and group H (HHC technique). A cementless cup was inserted in 25 hips (19 female, 6 male; mean age = 51 years, age range = 28-67)) at near-AHC in group A and 32 hips (22 female, 10 male; mean age = 53 years, age range = 29-68) at HHC position in group H. To assess clinical status, the Harris Hip Score (HHS) was used at the final follow-up. In radiographical assessment, component loosening and osseointegration of the acetabular cup were examined on follow-up radiographs. Complications were also recorded. RESULTS The mean follow-up was 41 months (range, 25-84) in group A and 40 months (range, 24-86) in group H. The mean HHS was 83 (range, 74-91) in group A and 83.6 (range, 73-94) in group H (p = 0.741). Osteolysis was determined in three patients from each group. The other 51 cups demonstrated a minimum of one radiographic sign of osseointegration. Although the overall complication rate was higher in group A (64%) than in group H (46%), this difference reached no statistical significance (p = 0.11). CONCLUSIONS The HHC technique using cementless acetabular fixation seems to be a valuable alternative option to AHC technique in cases of Crowe types II and III DDH. Key words: High hip center; anatomical hip center; center of rotation; total hip arthroplasty; dysplastic hip; developmental dysplasia of the hip; Crowe type II; Crowe Type III.

Root and canopy traits and adaptability genes explain drought tolerance responses in winter wheat.

Bread wheat (Triticum aestivum L) is one of the three main staple crops worldwide contributing 20% calories in the human diet. Drought stress is the main factor limiting yields and threatening food security, with climate change resulting in more frequent and intense drought. Developing drought-tolerant wheat cultivars is a promising way forward. The use of holistic approaches that include high-throughput phenotyping and genetic markers in selection could help in accelerating genetic gains. Fifty advanced breeding lines were selected from the CIMMYT Turkey winter wheat breeding program and studied under irrigated and semiarid conditions in two years. High-throughput phenotyping was done for wheat crown root traits and canopy senescence dynamics using vegetation indices (green area using RGB images and Normalized Difference Vegetation Index using spectral reflectance). In addition, genotyping by KASP markers for adaptability genes was done. Overall, under semiarid conditions yield reduced by 3.09 t ha-1 (-46.8%) compared to irrigated conditions. Genotypes responded differently under drought stress and genotypes 39 (VORONA/HD24-12//GUN/7/VEE#8//…/8/ALTAY), 18 (BiII98) and 29 (NIKIFOR//KROSHKA) were the most drought tolerant. Root traits including shallow nodal root angle under irrigated conditions and root number per shoot under semiarid conditions were correlated with increased grain yield. RGB based vegetation index measuring canopy green area at anthesis was better correlated with GY than NDVI was with GY under drought. The markers for five established functional genes (PRR73.A1 -flowering time, TEF-7A -grain size and weight, TaCwi.4A - yield under drought, Dreb1- drought tolerance, and ISBW11.GY.QTL.CANDIDATE- grain yield) were associated with different drought-tolerance traits in this experiment. We conclude that-genotypes 39, 18 and 29 could be used for drought tolerance breeding. The trait combinations of canopy green area at anthesis, and root number per shoot along with key drought adaptability makers (TaCwi.4A and Dreb1) could be used in screening drought tolerance wheat breeding lines.

Comparative evaluation of cost for preliminary and tertiary municipal wastewater treatment plants in Istanbul.

As the global economy continues to grow, the need for an economic evaluation of wastewater treatment plants (WWTPs) is increasing. Determination of cost functions (CFs) helps to assess the costs of WWTP and to be able to reach to the satisfactory financial levels of construction and operation practices in the early phases of a project. In this study, unit capital and operation and maintenance (O&M) costs were calculated by analyzing the real capital and operation and maintenance expenditures of 16 full-scale WWTPs in Istanbul. Besides, the impacts of treatment level and capacity on costs were investigated. The unit total capital cost was found as 0.013 ± 0.004 €/m3 and 0.054 ± 0.009 €/m3 for preliminary and tertiary treatment, respectively, whereas the unit total O&M cost were 0.011 ± 0.007 €/m3 and 0.077 ± 0.021 €/m3 for preliminary and tertiary treatment, respectively. Capital (investment) costs covered 58% of the total cost in preliminary WWTPs, whereas; O&M costs had the highest share (58%) in tertiary WWTPs. The results of this study confirmed that the level of treatment considerably affected the costs of WWTPs. Moreover, the CFs were separately derived for tertiary treatment including A2O with and without digester. The CFs obtained in this study are of utmost importance to be used in the economic evaluation of the planned WWTPs and in the management of existing ones.

Pathogenicity and Control of Phacidium lacerum, an Emerging Pome Fruit Pathogen in Washington State.

Phacidium lacerum (anamorph Ceuthospora pinastri) is a recently reported quarantine fungal pathogen responsible for postharvest rot in apples and pears. Very little is known about its pathogenicity, epidemiology, and best management practices. We screened pathogenicity of P. lacerum on twigs from seven and fruit from nine major commercial apple cultivars. Among the nine cultivars tested, detached fruit of Honeycrisp and Gala cultivars were the most susceptible, whereas WA38 (Cosmic Crisp) was the least susceptible (P < 0.05). Effective concentrations to inhibit 50% growth (EC50) were determined in 41 baseline P. lacerum isolates. The mean EC50 values for four postharvest fungicides, i.e., fludioxonil (FDL), difenoconazole (DIF), thiabendazole (TBZ), and pyrimethanil (PYRI) were 0.16, 0.38, 0.54, and 0.72 µg/ml, respectively. The mean EC50 values for four preharvest fungicides, i.e., pyraclostrobin (PYRA), fluxapyroxad (FLUX), boscalid (BOSC), and fluopyram (FLUP) were 0.96, 12.64, 16.54, and 44.46 µg/ml, respectively. In situ efficacy trials were conducted on detached Gala apples treated preventively and curatively with the aforementioned fungicides. After 6 months of storage at 1°C, FDL and DIF provided full control followed by TBZ and PYRI, whereas the other preharvest fungicides provided fair or low efficacies. Findings of this study shed light on pathogenicity of this emerging pathogen and provide necessary knowledge for effective management of Phacidium rot.

Reduced Virulence of an Introduced Forest Pathogen over 50 Years.

Pathogen incursions are a major impediment for global forest health. How pathogens and forest trees coexist over time, without pathogens simply killing their long-lived hosts, is a critical but unanswered question. The Dothistroma Needle Blight pathogen Dothistroma septosporum was introduced into New Zealand in the 1960s and remains a low-diversity, asexual population, providing a unique opportunity to analyze the evolution of a forest pathogen. Isolates of D. septosporum collected from commercial pine forests over 50 years were compared at whole-genome and phenotype levels. Limited genome diversity and increased diversification among recent isolates support the premise of a single introduction event. Isolates from the 1960s show significantly elevated virulence against Pinus radiata seedlings and produce higher levels of the virulence factor dothistromin compared to isolates collected in the 1990s and 2000s. However, later isolates have no increased tolerance to copper, used in fungicide treatments of infested forests and traditionally assumed to be a strong selection pressure. The isolated New Zealand population of this forest pathogen therefore appears to have become less virulent over time, likely in part to maintain the viability of its long-lived host. This finding has broad implications for forest health and highlights the benefits of long-term pathogen surveys.

Evolutionary relics dominate the small number of secondary metabolism genes in the hemibiotrophic fungus Dothistroma septosporum.

Fungal secondary metabolites have important functions for the fungi that produce them, such as roles in virulence and competition. The hemibiotrophic pine needle pathogen Dothistroma septosporum has one of the lowest complements of secondary metabolite (SM) backbone genes of plant pathogenic fungi, indicating that this fungus produces a limited range of SMs. Amongst these SMs is dothistromin, a well-characterised polyketide toxin and virulence factor that is required for expansion of disease lesions in Dothistroma needle blight disease. Dothistromin genes are dispersed across six loci on one chromosome, rather than being clustered as for most SM genes. We explored other D. septosporum SM genes to determine if they are associated with gene clusters, and to predict what their likely products and functions might be. Of nine functional SM backbone genes in the D. septosporum genome, only four were expressed under a range of in planta and in culture conditions, one of which was the dothistromin PKS backbone gene. Of the other three expressed genes, gene knockout studies suggested that DsPks1 and DsPks2 are not required for virulence and attempts to determine a functional squalestatin-like SM product for DsPks2 were not successful. However preliminary evidence suggested that DsNps3, the only SM backbone gene to be most highly expressed in the early stage of disease, appears to be a virulence factor. Thus, despite the small number of SM backbone genes in D. septosporum, most of them appear to be poorly expressed or dispensable for virulence in planta. This work contributes to a growing body of evidence that many fungal secondary metabolite gene clusters might be non-functional and may be evolutionary relics.

Evolution of polyketide synthesis in a Dothideomycete forest pathogen.

Fungal secondary metabolites have many important biological roles and some, like the toxic polyketide aflatoxin, have been intensively studied at the genetic level. Complete sets of polyketide synthase (PKS) genes can now be identified in fungal pathogens by whole genome sequencing and studied in order to predict the biosynthetic potential of those fungi. The pine needle pathogen Dothistroma septosporum is predicted to have only three functional PKS genes, a small number for a hemibiotrophic fungus. One of these genes is required for production of dothistromin, a polyketide virulence factor related to aflatoxin, whose biosynthetic genes are dispersed across one chromosome rather than being clustered. Here we evaluated the evolution of the other two genes, and their predicted gene clusters, using phylogenetic and population analyses. DsPks1 and its gene cluster are quite conserved amongst related fungi, whilst DsPks2 appears to be novel. The DsPks1 protein was predicted to be required for dihydroxynaphthalene (DHN) melanin biosynthesis but functional analysis of DsPks1 mutants showed that D. septosporum produced mainly dihydroxyphenylalanine (DOPA) melanin, which is produced by a PKS-independent pathway. Although the secondary metabolites made by these two PKS genes are not known, comparisons between strains of D. septosporum from different regions of the world revealed that both PKS core genes are under negative selection and we suggest they may have important cryptic roles in planta.

Carpal Tunnel Syndrome Surgery Anti-Adhesion Gel Is Effective?

PURPOSE OF THE STUDY The purpose of the current study is to assess the efficacy of anti-adhesion gel on the symptom severity and functional outcomes after mini incision open surgery for carpal tunnel syndrom (CTS). MATERIAL AND METHODS A total of 200 CTS patients (154 women, 46 men) were included in this study. Group I (n = 100; 78 women, 22 men) did not receive local administration of anti-adhesion gel, while anti-adhesion gel consisting of hyaluronic acid-carboxymethylcellulose (Seprafilm®, SanofiBiosurgery, Bridgewater, NJ, USA) was locally applied to patients in Group II (n = 100; 76 women, 24 men). All patients recruited in this study had received conservative treatment comprised of non-steroidal antiinflammatory drugs, steroid injection, replacement of vitamin B and stabilization with splints. Cases that did not benefit from these therapeutic options during one year were assigned as candidates for surgical treatment. RESULTS There was no significant difference between two groups in terms of mean age, gender distribution, preoperative and postoperative Boston questionnaire (BQ) scores, difference of BQ scores after the operation, and the presence of the disease on the left or right side. According to postoperative 1. Year results, there was no significant difference between two groups. CONCLUSIONS Results of the current study demonstrated that use of anti-adhesion gel during mini incision open surgery for CTS did not bring about significant advantages in terms of functional or symptomatic outcomes. Further, controlled trials on larger series are warranted to understand the beneficial effects of anti-adhesive materials during the surgical treatment of CTS. Key words: anti-adhesion gel, Boston questionnaire, carpal tunnel syndrome.

Comparison of relationship between histopathological, serological and biochemical parameters in patients with chronic hepatitis B infection.

OBJECTIVE: To demonstrate the relationship between liver histology, alanine aminotransferase (ALT)/aspartate aminotransferase (AST) and hepatitis B virus (HBV) DNA levels based on hepatitis B e antigen (HBeAg) seropositivity status in naive patients with chronic hepatitis B (CHB). MATERIALS AND METHOD: Naive patients with CHB admitted to our hospital between January 2012 and April 2014 were evaluated retrospectively. The patients were allocated into one of two groups based on HBeAg-seropositivity status. RESULTS: Two hundred and fourteen patients were enrolled in the study. Of these 214 patients, 103 (48.1%) were HBeAg-positive and 111 (51.9%) were HBeAg-negative. In the HBeAg-positive group, positive correlations were found between histologic activity index (HAI) scores and ALT (t=3.3, r=0.31, p=0.001), AST (t=2.8, r=0.27, p=0.005) and HBV DNA load (t=2.5, r=0.24, p=0.014). Additionally, in this group, fibrosis scores had positive correlations with ALT (t=3.3, r=0.32, p=0.001) and AST (t=2.7, r=0.26, p=0.008). In the HBeAg-negative group, positive correlations were found between HAI scores and ALT (t=3, r=0. 28, p=0.003), AST (t=3, r=0. 28, p=0.003) and HBV DNA (t=5.3, r=0. 45, p=0). In this same group, fibrosis scores had a positive correlation with HBV DNA (t=2.2, r=0. 21, p=0.024). Multivariate logistic regression analysis showed a positive relationship between fibrosis and ALT in the HBeAg-positive group and a positive relationship between fibrosis and HBV DNA load in the HBeAg-negative group. CONCLUSIONS: This study showed that HBV DNA load is an independent predictive factor for evaluating HAI and fibrosis in the HBeAg-negative group. Also, ALT is an independent predictive factor for evaluating fibrosis in the HBeAg-positive group.

New antimony(III) halide complexes with dithiocarbamate ligands derived from thiuram degradation: The effect of the molecule's close contacts on in vitro cytotoxic activity.

Antimony(III) halide complexes of the formulae {[SbBr(Me2DTC)2]n} (1), {[SbI(Me2DTC)2]n} (2) and {[(Me2DTC)2Sb(µ2-I)Sb(Me2DTC)2](+).I3(-)} (3) (Me2DTC = dimethyldithiocarbomate) were synthesized from SbX3, (X = Br or I) and tetramethylthiuram monosulfide (Me4tms) or tetramethylthiuram disulfide (Me4tds). The complexes were characterized by melting point (m.p.), elemental analysis (e.a.), Fourier-transform Infra-Red (FT-IR), Fourier-transform Raman (FT-Raman), Nuclear Magnetic Resonance ((1)H,(13)C-NMR) spectroscopy and Thermogravimetric-Differential Thermal Analysis (TG-DTA). Crystal structures of complexes 1-3 were determined with single crystal X-ray diffraction analysis. Complexes 1 and 2 are polymers with distorted square pyramidal (SP) geometry in each monomeric unit, whereas complex 3 is ionic, containing an iodonium linkage Sb-I(+)-Sb and an I3(-) counter anion; to the best of our knowledge, this is the first ionic antimony(III) iodide complex. The in vitro cytotoxic activity of 1-3 against human adenocarcinoma cells: breast (MCF-7) and cervix (HeLa) cells and non-cancerous cells: MRC-5 (normal human fetal lung fibroblast cells) was evaluated with trypan blue (TB) and sulforhodamine B (SRB) assays. Among antimony(III) compounds with sulfur containing ligand, those of dithiocarbamates exhibit significant cytotoxic activity. Hirshfeld surface volumes were analyzed to clarify the nature of the intermolecular interactions by the 2D fingerprint plot. Molecules with lower H-all atoms inter-molecular interactions exhibit the higher activity against MCF-7 cells. The in vivo genotoxicity of 1-3 was evaluated by the mean of Allium cepa test. Alterations in the mitotic index values due to the chromosomal aberrations were observed in the case of complexes 2 and 3. Since, no such alteration is caused by 1, it makes this compound candidate for further study as potential drug.

Tear function alterations in patients with polycystic ovary syndrome.

OBJECTIVE: Complaints of dry eye are prevalent worldwide and are known to be associated with insulin resistance (IR) and hyperandrogenism. However, dry eye is often overlooked in the context of polycystic ovary syndrome (PCOS). The aim of the present study was to evaluate whether or not there is any relation between tear functions and PCOS, which is a multifaceted disorder associated with IR or hyperandrogenism. PATIENTS AND METHODS: A total of 35 women with polycystic ovary syndrome (PCOS) were enrolled in this study, along with 27 healthy controls. Body mass index (BMI), follicle-stimulating hormone (FSH), luteinizing hormone (LH) and free testosterone levels on the third day of menstruation were recorded, as well as hirsutism score (using the Ferriman Gallwey scoring system), insulin resistance (homeostasis model assessment), neutrophil-to- lymphocyte ratios (NLR), platelet-to-lymphocyte ratios (PLR), and mean platelet volumes (MPV). A complete ocular examination was followed by administration of the ocular surface disease index (OSDI) questionnaire and Schirmer and tear break-up time (TBUT) tests. RESULTS: Schirmer and OSDI results were similar between groups, but TBUT was significantly lower in the PCOS group (p = 0.002). There were negative correlations between FG score and TBUT test (r = -0.406, p = 0.001) and between NLR and Schirmer test (r = -0.294, p = 0.025). CONCLUSIONS: Although subjective dry eye symptoms do not present in all patients, these results confirm that tear reduction, which can cause further complications in patients with PCOS, can be detected by careful examination and sensitive tests.

Recent advances on antimony(III/V) compounds with potential activity against tumor cells.

Antimony one of the heavier pnictogens, has been in medical use against microbes and parasites as well. Antimony-based drugs have been prescribed against leishmaniasis since the parasitic transmission of the tropical disease was understood in the beginning of the 20th century. The activity of arsenic against visceral leishmaniasis led to the synthesis of an array of arsenic-containing parasitic agents, among them the less toxic pentavalent antimonials: Stibosan, Neostibosan, and Ureastibamine. Other antimony drugs followed: sodium stibogluconate (Pentostam) and melglumine antimoniate (Glucantim or Glucantime); both continue to be in use today despite their toxic side effects and increasing loss in potency due to the growing resistance of the parasite against antimony. Antimony compounds and their therapeutic potentials are under consideration from many research groups, while a number of early reviews recording advances of antimony biomedical applications are also available. However, there are only few reports on the screening for antitumor potential of antimony compounds. This review focuses upon results obtained on the anti-proliferative activity of antimony compounds in the past years. This survey shows that antimony(III/V) complexes containing various types of ligands such as thiones, thiosemicarbazones, dithiocarbamates, carboxylic acids, or ketones, nitrogen donor ligands, exhibit selectivity against a variety of cancer cells. The role of the ligand type of the complex is elucidated within this review. The complexes and their biological activity are already reported elsewhere. However quantitative structure-activity relationship (QSAR) modeling studies have been carried out and they are reported for the first time here.

In vitro effect of moxifloxacin and rifampicin on biofilm formation by clinical MRSA isolates.

OBJECTIVE: In this study, it was aimed to investigate in vitro activity of moxifloxacin and rifampicin on biofilm formation by clinical MRSA isolates. BACKGROUND: Methicillin resistant Staphylococcus aureus (MRSA) strains could be the causative agent in chronical and medical device associated infections by biofilm formation. METHODS: Moxifloxacin and rifampicin MIC values of 98 MRSA clinical isolates were determined by microdilution method. Biofilm formation of all isolates was determined in 96-well microplates by using spectrophotometric method. Effects of MIC and sub-inhibitory concentrations (1/2 and 1/4 MIC) of antibiotics on biofilm formation were examined in 46 strong biofilm producer strains. RESULTS: Biofilm production decreased in 37 and 44 isolates at all studied concentrations of moxifloxacin and rifampicin, respectively. Biofilm production increased in six isolates with moxifloxacin and in two isolates with rifampicin. CONCLUSION: Biofilm inhibitory effect of rifampicin was found to be stronger than moxifloxacin in the examined strains. The studied antimicrobials also induced biofilm formation in some strains. Results of this study may help to evaluate the effects of these antibiotics on biofilm formation of clinical MRSA strains and to control the antibiotic resistance in clinical settings (Tab. 2, Ref. 25).

Infected primary hydatid cyst located in the Sartorius muscle.

Primary intramuscular hydatid cyst should be considered for the differential diagnosis of cystic soft tissue masses especially in the endemic areas though primary muscular hydatidosis is a rare clinical entity. We aimed to report the case of a 30-year-old female patient with infected primary intramuscular hydatid cyst located in the sartorius muscle.

Comparison of intracompartmental pressures in a rabbit model of open and closed tibial fractures: an experimental study.

We compared the intracompartmental pressures (ICPs) of open and closed tibial fractures with the same injury pattern in a rabbit model. In all, 20 six-month-old New Zealand White male rabbits were used. They were randomised into two equal groups of ten rabbits; an open fracture group (group 1) and a closed fracture group (group 2). Each anaesthetised rabbit was subjected to a standardised fracture of the proximal half of the right tibia using a custom-made device. In order to create a grade II open fracture in group 1, a 10 mm segment of fascia and periosteum was excised. The ICP in the anterior compartment was monitored at six-hourly intervals for 48 hours. Although there was a statistically significant difference in ICP values within each group (both p < 0.001), there was no significant difference between the groups for all measurements (all p ≥ 0.089). In addition, in both groups there was a statistically significant increase in ICP within the first 24 hours, whereas there was a statistically significant decrease within the second 24 hours (p < 0.001 for both groups). We conclude that open tibial fractures should be monitored for the development of acute compartment syndrome to the same extent as closed fractures.

Biochemical markers in total intravenous anesthesia and propofol infusion syndrome: a preliminary study.

OBJECTIVES: To investigate biochemically whether total intravenous anesthesia (TIVA) using propofol creates a risk for Propofol Infusion Syndrome (PRIS). PATIENTS AND METHODS: Forty patients scheduled for thyroid gland surgery were randomly assigned into Group T or C and premedicated 30 min before operation. Group T received remifentanyl hydrochloride, propofol infusion following anesthesia induction with propofol, vecuronium bromide and intubation. Group C received remifentanyl hydrochloride infusion, 1-1.5 MAC desflurane inhalation following anesthesia induction with thiopental, vecuronium bromide and intubation. Patients were respired 50% O2-air mixture. Blood gas, potassium, lactic acid, CK-MB, myoglobin, troponin I, total carnitine, triglyceride, creatinine concentrations were determined before operation, at intraoperative hour-2, postoperative hour-6. RESULTS: There were no significant differences between groups in potassium, lactic acid CK-MB, myoglobin, total carnitine or creatinine levels. Triglyceride level at intraoperative hour-2 increased in Group T, decreased at postoperative hour-6. Troponin I was higher in Group C than Group T at intraoperative hour-2 (p < 0.05). No asystole, bradycardia, arrhythmia, hypotension or change in urine color was detected. CONCLUSIONS: The present biochemical findings suggest that TIVA using propofol is safe.

Stability analysis of a mathematical model in a microcosm with piecewise constant arguments.

In this paper, we have modeled a population density of a bacteria species in a microcosm by using a differential equation, [Formula in text] where t ≥ 0, the parameters r, α, ß(0) and ß(1) denote positive numbers ann [t] denotes the integer part of [Formula in text]. First, to obtain the local and global behaviors, the boundedness character and the periodic nature of the population density for bacteria, discrete solutions of differential Eq. (A) is investigated. Examinations of the stability characterization of (A) show that increasing of the population growth rate decreases the local stability of the positive equilibrium point. Due to this result we need to consider a second approximation to obtain stability of population density. This can be performed at low density by incorporating an Allee function to (A) at time t. For the theoretical results obtained here we give an example by taking some parameter values from experimental data of bacteria populations [8] and show that the experimental and theoretical results for both models with and without Allee effect are in good agreement.

Confectionery industry: a case study on treatability-based effluent characterization and treatment system performance.

Source-based wastewater characterization and stream segregation provide effective management of industrial wastewaters. The characterization of wastewater sources from a confectionery factory was presented and performance of the wastewater treatment plant was evaluated in this study. All of the wastewater sources in the factory, except the vacuum water line, can be characterized by high concentrations of soluble pollutants and low pH. High organic content of the wastewater generated from the confectionery industry promoted the application of anaerobic technology as a pre-treatment before the conventional aerobic treatment. The average chemical oxygen demand (COD) removal and biogas production for expanded granular sludge bed reactor were 88% and 1,730 Nm(3)/day, respectively. The effluent from the investigated facility can be used for irrigation provided that conductivity values are within acceptable limits.

The feasibility of a centralized biogas plant treating the manure produced by an organized animal farmers union in Turkey.

The aim of this study is to evaluate the feasibility and the energy recovery potential of mesophilic (30-35 °C) anaerobic digestion of animal wastes (manure) at a centralized biogas plant (CBP) for 35,000 cattle. The proposed CBP is composed of an equalization tank followed by pasteurization and 3+[1/2] modules; i.e. each module consists of four completely mixed anaerobic reactors with a capacity of treating the manure from 10,000 cattle. The effect of maize silage loading, as the co-substrate, both on biomethane production and feasibility of the system was also evaluated. Besides, the transport fuel substitutes of the produced biomethane with or without co-substrate were also investigated. Results of the proposed CBP indicated that biomethane production increased ca. 1.65 fold with co-substrate addition and pay-back periods for one module treating 10,000 cattle manure are calculated to be ca. 11 and 7.0 yr without and with silage addition, respectively. Besides, considering the potential revenue when replacing transport fuels, about 74 heavy goods vehicles or 1,560 cars may be powered per year by the biogas produced from the proposed CBP where the co-digestion of manure and maize silage is applied.