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Micropollutants such as endocrine disruptors are one of the most important groups of chemicals polluting water resources. Conventional treatment systems may not be effective for the removal of endocrine disrupting chemicals (EDCs), and the fate of these chemicals should be carefully monitored in the effluent of wastewater treatment plants (WWTPs). Additional treatment methods such as advanced oxidation processes can be used for the removal of endocrine disruptors. This study presents the existence of endocrine disruptors in 4 different effluents: (i) municipal WWTP effluent, (ii) textile industry WWTP effluent, (iii) organized industrial zone (OIZ) WWTP effluent and (iv) pharmaceutical industry discharge and also presents their removal efficiencies by ozonation and peroxone oxidation. A broad spectrum of removal efficiencies was observed for the EDCs present in the samples since the oxidation efficiency of wastewaters containing EDCs mainly depends on the wastewater matrix and on the type of the EDCs. Ozonation was found to be a lower-cost option than peroxone oxidation at the investigated conditions.

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Diffuse pollution is hard to analyze, control and manage by its nature. Watershed models and Geographical Information Systems (GIS) are recently developed tools that aid analysis of diffuse sources of pollution. However, their applications are not always easy and straightforward. Turkey is a typical example of a mountainous country rich in rivers and streams. Due to the complex geomorphology, land-use and agricultural practices in most of the watersheds in Turkey, modelling, analyzing and managing diffuse pollution has been a challenge. The complex watershed structure forces the modellers to work with spatially high resolution data. Apart from the data, the models themselves may also cause operational problems. These issues and their probable solutions form the basis of the discussions in this paper. It acts as a guideline for modelling and analyzing diffuse pollution by emphasizing the referred problems and difficulties. Design of an Information Technology-based system tool for watershed and/or water quality modelling, which would be suitable for countries having watersheds with similar structure and problems to those of Turkey, is also outlined.

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Diffuse pollution is usually temporally and spatially uncertain, and thus hard to analyze. In many cases, discretizing a diffuse source of pollution into individual point sources can ease diffuse pollution modelling and analysis, and therefore reduce high uncertainty especially in the spatial distribution of pollution loads. This is however a difficult task, since quite a number of sub-drainage areas, with complex structures and land-use properties, has to be delineated. Watershed models can be used to delineate the sub-drainage areas in a watershed with high accuracy and locate the related outlets which connect the sub-drainage areas to the main waterbody in a watershed. In this study, such an approach has been used on a case study to model the diffuse nutrient loads carried to streams that reach to a medium-sized lake in Turkey. The annual nutrient loads, which were calculated by using mathematical models, were then converted to a load-map with the help of a geographical information system.

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Reuse of wastewater for irrigational purposes in agriculture has been a widely applied practice all around the world compared to such applications in industries. In most of the developing countries, high costs of wastewater treatment stimulate the direct reuse of raw or partly treated effluent in irrigation despite the socio-cultural objections in some countries regarding religious rituals towards consuming wastewater. In Turkey, reuse applications in agriculture have been in use by indirect application by means of withdrawing water from the downstream end of treatment plants. Such practices affected the deterioration of surface water resources due to the lack of water quality monitoring and control. However, more conscious and planned reuse activities in agriculture have recently started by the operation of urban wastewater treatment plants. Turkey does not face any severe water scarcity problems for the time being, but as the water resources show the signs of water quality deterioration it seems to be one of the priority issues in the near future. The industrial reuse activities are only at the research stage especially in industries consuming high amounts of water. In-plant control implementation is the preferred effort of minimizing water consumption in such industries. The current reuse activities are outlined in the article forming an example from a developing country.

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The study covers the investigation of pesticides in terms of consumption, toxicological classification and various intrinsic physical and chemical properties like DT50, KOC, GUS, solubility that describe the important mechanisms prevailing in soil, namely persistence and mobility. These mechanisms help to estimate the transportation pathways of pesticides on soil till they reach the receiving water after being applied on land. Classification is done in three groups, those likely to appear in surface flow, those that appear in groundwater and those that present transient conditions. Such an approach that also takes into account toxicological levels and annual consumption values of pesticides will act as a tool to prepare the priority list of pesticides that need special care during their transportation. The fate of pesticides is a difficult task to solve, however, such a methodology, puts forth a rough estimate on their behavior in spite of uncertainties in many of the parameters describing mechanisms like persistence and mobility. The agricultural areas of two watersheds of Istanbul are selected as target areas to describe the approach, which is also checked with another approach estimating pesticide pollution potential that considers various other properties of pesticides. Almost similar findings are depicted with 85% proximity. The methodology presented in the paper illustrates and emphasizes the significant role of pesticide properties in determining their fate in soil after being applied.

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Wetlands are of utmost importance in the sense of protecting the natural ecological balance of the environment. It is possible to improve the water quality of wetlands, which are located in coastal areas like river deltas and lakes without disturbing the ecological balance through rehabilitation and by controlling. However, many wetlands in the world have so far been dried and converted to agricultural areas due to insufficient knowledge of their ecological value. Such an understanding was also held as true in Turkey and most of its wetlands have been converted to agricultural land till recent years. An example of such an occurrence and modifications within years are observed in the delta of the Kizilirmak River, which is the longest river of Turkey ending in the Black Sea. The past and present situation of the Kizilirmak delta will be investigated in this paper together with the changes in water quality. An evaluation of the water quality of the river and of lakes within the delta is done based on available previous data and on the final findings of water quality measurements conducted within the framework of this study.

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Pesticides used on agricultural lands are among the significant diffuse sources of pollutants. They are poisons and can be particularly dangerous when misused and/or applied without care. Although certain characteristics of pesticides are well known, their final characteristics after they reach a waterbody are extremely difficult to estimate. Regarding the soil and water environment, it is necessary to conduct both a field study and laboratory analysis. Such a study has been performed in the catchment area of Dalyan Lagoon, Turkey, joining the Mediterranean Sea, that was selected as the pilot region. The input of pesticides, transport in soil and transfer to the water environment together with their probable impacts on water quality are determined by conducting detailed field surveys and water residue analyses. Within the scope of the study, the behavior and fate of pesticides both in soil and water are investigated in detail. Water residue experiments are conducted on four sets of water samples representing the seasons of the year 1999-2000 for the pre-selected 6 pesticides. Two sets of water samples (surface and bottom) are taken from the 16 stations along the lagoon channel and two lakes within the catchment area. The results and findings show the significance of the use of pesticides as they exist in the water environment around and/or slightly above the limits stated in the national current regulations except dichlorvos which presents very high values compared to its tolerance limit. Of particular interest, the results are used to enlighten the farmers and the public and increase awareness of pesticides as contaminants in valuable coastal waters.

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Allopurinol has been widely used to reduce the severity of the reperfusion injury. However, conflicting data have been reported regarding the dosage, the duration of the timing, and the administrative regimen of the drug. The aim of this study was, therefore, to evaluate the effects of short versus long periods of allopurinol pretreatment on the anastomotic healing of intestines, directly after being subjected to ischemia-reperfusion (IR) stress. Furthermore, the effects of an allopurinol pretreatment on the survival rate following IR stress, was also assessed. One hundred thirty-seven male Wistar rats with a median weight of 235 (range, 180-275) g used in the study. In group I (control group, N = 20) superior mesenteric artery (SMA) and collateral vessels were isolated but not occluded. In group II, the profound IR group (PIR, N = 42), the SMA was occluded immediately distal to the aorta with collateral interruption using an atraumatic arterial clip for 30 min. In group III [two days of allopurinol (ALL) pretreatment group, 2ALL, N = 38], allopurinol (100 mg/kg body wt) was given intraperitoneally on a daily basis for two days prior to the experiment. In group IV (seven days of allopurinol pretreatment group, 7ALL, N = 37), the same pretreatment and the allopurinol schedule was performed for seven days before surgery. All animals underwent 3 cm of ileal resection and primary anastomosis, 10 cm proximal to ileocecal valve. Within each group, animals were anesthetized either on the third or seventh postoperative days. Abdominal wound healing, intraabdominal adhesions, anastomotic complications, anastomotic bursting pressure measurements, and bursting site were recorded as were the histopathologic evaluation. No rats in group I, 20 rats in group II, 18 rats in group III, and 7 rats in group IV died (P = 0.0003). Anastomotic dehiscence was found in one of 20 group I, in 11 of 22 in group II, in 9 of 20 in group III, and in 3 of 30 in group IV (P = 0.0003). On the third and seventh days, the median bursting pressures of the anastomosis were determined: 42 and 235 mm Hg in group I, 17 and 105 mm in Hg in group II, 22 and 183 mm Hg in group III, and 36 and 214 mm Hg in group IV (P < 0.0001). The burst occurred at the anastomoses in all animals tested on the third postoperative day, one in group I, six in group II, four in group III and one in group IV on the seventh postoperative day (P < 0.01). All deleterious effects of reperfusion injury on intestinal anastomosis healing, including survival rates and the histopathological parameters, were significantly prevented by seven days, but not two days, of high-dose allopurinol pretreatment.

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Providing clean water at relevant quality and quantity is a challenge that regulatory authorities have to face in metropolitan cities that seem to develop at their limits of sustainability. Istanbul strives to face such a challenge for its population of over 10 million, through six surface water resources. Two approaches of classification for the reservoirs are presented, one based on current regulations and an alternative based on a more detailed classification. The results have shown that nutrient control is the primary issue, and one of the reservoirs has already exceeded the limits of being eutrophic, one is at mesotrophic conditions, and the remaining four are at the limit of being eutrophic, indicating the significance of making the correct decision and taking pertinent measures for management and control. It has been observed that the only mesotrophic resource, which also has the best general quality class, has no industry and a very low population density, whereas the one that is already eutrophic is also the one with the lowest quality class, has the highest population density, and has the greatest percentage of urban land use within its watershed.

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Intestinal ischemia/reperfusion provokes a local inflammatory response leading to a systemic inflammatory state. In this study we aimed to assess the effects of intestinal ischemia/reperfusion injury on anastomotic healing in the left colon with an intact vascular supply. A total of 94 Wistar albino rats were divided into three groups: sham-operated control (group I, n = 25), 30 minutes of intestinal ischemia/reperfusion (group II, n = 40), and 7-day allopurinol pretreatment and intestinal ischemia/reperfusion (group III, n = 29). After the reperfusion experiment, a segmental left colon resection and anastomosis were done. On postoperative days 3 and 7 anastomotic bursting pressure, anastomotic and operative complications, and intraabdominal adhesions were assessed. Mortality rates were 1/25, 16/40, and 4/29 for groups I, II, and III, respectively (p = 0.001). There was no difference among the groups for wound and anastomotic healing parameters evaluated by macroscopic criteria. On postoperative day 7 the mean bursting pressures were 220.3 +/- 18.5, 162.0 +/- 21.0, and 213.9 +/- 24.7 for groups I, II, and II, respectively (p = 0.000). Significantly dense adhesions were found in group II (p = 0.000). Allopurinol pretreatment prevented the effects of ischemia/reperfusion on anastomotic healing of the left colon. Intestinal/ischemia reperfusion causes impairment of anastomotic healing of the left colon. In addition to remote organ effects, reperfusion injury may affect anastomotic healing in the viscera with an intact vascular supply.

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The six main drinking water reservoirs of Istanbul are under the threat of pollution due to rapid population increase, unplanned urbanisation and insufficient infrastructure. In contrast to the present land use profile, the environmental evaluation of the catchment areas reveals that point sources of pollutants, especially of domestic origin, dominate over those from diffuse sources. The water quality studies also support these findings, emphasising that if no substantial precautions are taken, there will be no possibility of obtaining drinking water from them. In this paper, under the light of the present status of the reservoirs, possible and probable short- and long-term protective measures are outlined for reducing the impact of point sources. Immediate precautions mostly depend on reducing the pollution arising from the existing settlements. Long-term measures mainly emphasise the preparation of new land use plans taking into consideration the protection of unoccupied lands. Recommendations on protection and control of the reservoirs are stated.

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BACKGROUND/AIMS: Significant bacterial translocation was demonstrated following experimental biliary obstruction, however very little is known about the importance and the prevalence of gut-origin sepsis in obstructive jaundice patients. Therefore, the aim of this study was to investigate the concept of gut-origin sepsis in obstructive jaundiced patients and its clinical importance. METHODOLOGY: Twenty-one patients requiring laparotomy for obstructive jaundice (group I) and thirty patients operated on electively mainly for chronic cholecystitis (group II) were studied. Peritoneal swab, mesenteric lymph node, portal venous blood, liver wedge biopsy and bile were sampled for culture immediately after opening the peritoneum. Additionally, peripheral blood samples were taken pre- and post-operatively from all patients. Post-operatively, patients were monitored for infectious complications. RESULTS: The mean serum bilirubin concentration, gamma glutamyl transferase and alkaline phosphatase levels in jaundiced patients before therapeutic intervention were significantly higher than in control patients. Five patients demonstrated bacterial translocation in group I (24%), whereas only one did so in group II (3.5%, p < 0.05). Septic complications were detected in three patients, but only in two with bacterial translocation in group I. There was one patient with bacterial translocation who had septic complication in group II. CONCLUSIONS: The present study demonstrated that obstructive jaundice significantly promotes bacterial translocation in humans, however, its clinical importance has yet to be defined.

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Small bowel enteroscopy has been reported useful in the non-surgical evaluation of the small intestine in patients with obscure gastrointestinal bleeding but findings may be limited due to incomplete small bowel intubation and a lack of tip deflection. Intra-operative enteroscopy (IOE) is accepted as the ultimate diagnostic procedure for complete evaluation of the small bowel in these patients. Two patients with obscure gastrointestinal bleeding and deep anemia underwent IOE during surgical exploration. Angiodysplastic lesion with a diameter of 3 cm was found at jejunum in the first patient and segmental jejunal resection was performed. Enteroscopy showed red punctate lesions with a diameter of 1-3 mm located at proximal jejunum and extending to the ileum in the second patient. Total jejunal resection was performed. There was no recurrence of gastrointestinal bleeding during 36 months follow-up.

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Although classic open surgery is simple, expeditious, and effective, it has some drawbacks, including wound sepsis, delayed recovery, operative difficulties, and possibility of unnecessary appendectomies for false appendicitis. The aim of this study was to assess the applicability and safety of laparoscopic appendectomy (LA) in a prospectively randomized trial. Seventy nonselective patients with suspected appendicitis were randomized to laparoscopic (n = 35, 17 male) or open appendectomy (n = 35, 15 male) and operated on an emergency basis. Operative findings, operating time, postoperative complications, and length of hospital stay were compared. We found that LA is associated with a shorter hospital stay, fewer postoperative complications, and better diagnostic accuracy, and it is recommended as the procedure of choice for the diagnosis and management of acute appendicitis.

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BACKGROUND: Revascularization of ischemic bowel may induce further local tissue damage due to reperfusion injury. Therefore, we aimed to investigate the effect of ischemia-reperfusion injury on the healing of intestinal anastomosis in experimental models. METHODS: One hundred and two male Wistar rats were divided into three groups: a control group (group I, n = 23); an ischemia group (group II, n = 32), in which only the superior mesenteric artery (SMA) was occluded for 30 minutes; and a profound ischemia group (group III, n = 47), in which SMA was occluded as well as collateral vessels for 30 minutes. The pulsations were seen to return to marginal vessels and the bowels began to appear pinker and healthier in all groups following the restoration of arterial flow. Then, all animals underwent a 3-cm ileal resection and primary anastomosis, 10 cm proximal to the ileocecal valve. Within each group, animals were anesthetized either on the third or seventh postoperative days. Abdominal wound healing, intraabdominal adhesions, anastomotic complications, anastomotic bursting pressure measurements, and bursting site were recorded. RESULTS: Statistically significant differences were detected in intraperitoneal adhesion scores in group II and III (P <0.001). Anastomotic dehiscence was found in 2 of 23 (9%) in group I, 5 of 32 (16%) in group II, and 16 of 47 (34%) in group III (P <0.001). On the third and seventh days, the median bursting pressures of the anastomosis were determined to be 42 mm Hg and 250 mm Hg in group I, 46 and 253 in group II, and finally 19 and 90 mm Hg in group III (P <0.01). The burst occurred at the anastomoses in all animals tested on the third postoperative day, none in group I, 4 (28%) in group II, and 8 (67%) in group III on the seventh postoperative day (P <0.005). CONCLUSION: The present study demonstrated that ischemia-reperfusion impairs anastomotic healing. Despite the fact that the intestines are well perfused and viable after revascularization, one must bear in mind that intestinal reperfusion may compromise anastomotic healing.

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Harvesting split-thickness skin grafts from the abdomen is difficult when using a conventional hand dermatome. In this study, pneumoperitoneum was created in 10 patients before skin grafts were taken. No complications arose from the insufflation, and the conventional dermatome was then easy to use. Pneumoperitoneum provides more abdominal surface area, allowing the surgeon to harvest a greater number of larger, more uniform grafts during a single procedure, even when working near an anatomical protuberance.

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PURPOSE: Prospective, randomized studies have shown that bowel preparation may adversely affect infectious complications following colonic resections. However, very little is known about the effects of bacterial translocation on these infectious complications. The aim of this prospective, randomized study was to assess the effects of bowel preparation on bacterial translocation. METHODS: A total of 82 consecutive patients undergoing elective abdominal operations were randomly assigned to four groups: control (I; n = 20), mechanical (II; n = 21), mechanical plus oral metronidazole (III; n = 20), and polyethylene glycol preparation (IV; n = 21). Patients with intra-abdominal infection, those receiving preoperative antibiotics for any reason, and those having lower gastrointestinal tract disease were excluded from the study. Peritoneal swab, ileocecal and pericolic mesenteric lymph nodes, liver wedge biopsy, portal venous blood, and peripheral blood samples were taken for culture. Patients were followed up for postoperative infectious complications. Groups were matched according to age, gender, body surface area, and Acute Physiology and Chronic Health Evaluation II scores. RESULTS: Bacterial translocation was identified by a positive culture in one patient in Group I, two in Group II, one in Group III, and three in Group IV, respectively. Differences in number of positive cultures among the groups were not statistically significant. Nine patients had major infectious complications. Only two had bacterial translocation, and the same micro-organisms grew in both patients, in one at the wound site and in the other at the cyst abscess. CONCLUSION: This study demonstrated that mechanical bowel preparation does not enhance the spontaneous occurrence of bacterial translocation in patients without any clinical signs of lower gastrointestinal tract disease.

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/ Land-based point and diffuse pollution sources in the catchment area of Lake Sapanca, Turkey, were investigated. The present and future distribution of pollution loads were evaluated in terms of nitrogen, phosphorus, biochemical oxygen demand, and pesticides. A methodology for the estimation of pollution loads was presented; most of which were based on "unit loads." Presently domestic and industrial point sources dominate over diffuse sources including fertilizers and pesticides from agricultural use, nutrient loads from forests and meadows, urban runoff, and leachates from unregulated dumps of solid wastes. For the future, the aim of the control action is to maintain the sustainability of the water quality of the lake, at least at the second class of European Community standards. Within this framework; urgent/short-term and medium/long-term control actions will be exercised. In the urgent/short-term stage, simpler and natural ways of treatment will be employed. In the medium/long-term stage an integrated collection and treatment system will be put on operation. After completion of a proposed collection system and treatment plants to handle point sources, the control of diffuse sources will be more significant. Control of diffuse sources for the abatement of further deterioration of water quality then becomes the key issue to be emphasized in the Lake Sapanca catchment area. Diffuse sources control will be achieved by dividing the catchment area into three major protection zones. Use of pesticides and fertilizers on agricultural land and all other activities within these protection zones will be accomplished according to control plans, which will be supervised by an institution established to be responsible of all the activities within the basin.KEY WORDS: Diffuse sources; Land-based pollution; Nutrients; Pesticides; Point sources; Protection zones

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In pregnant women with a history of cesarean section, wall thickness of the lower uterine segment may help determine the risk and safety of vaginal delivery. Determination of wall thickness may help identify the potential risk of uterine rupture in pregnant women who do not wish to have another cesarean section or who are not eligible for surgery due to other systemic disorders. In this study, 50 pregnant women with previous cesarean sections were evaluated with ultrasound preoperatively, and measurements of the lower uterine segment wall thickness were compared with intraoperative assessment of uterine thinning. These findings correlated highly with each other (sensitivity: 100%; specificity: 82% positive predictive value: 87%; negative predictive value: 100%), suggesting the reliability and safety of ultrasound in evaluating uterine wall thickness.

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We reviewed the computed tomographic (CT) studies of 105 adults with various complaints. Spinal canal diameters were measured by CT using both the conventional and Jones-Thomson (JT) techniques at the level of the fourth lumbar vertebra. The data were statistically assessed in an attempt to define spinal stenosis.

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