91 research outputs found
Understanding of Prospective Mathematics Teachers of the Concept of Diagonal
This study aims to investigate the concept images of prospective mathematics teachers about the concept of diagonal. With this aim, case study method was used in the study. The participants of the study were consisted of 7 prospective teachers educating at the Department of Mathematics Education. Criterion sampling method was used to select the participants and the criterion was determined as taking the course of geometry in the graduate program. Data was collected in two steps: a diagnostic test form about the definition and features of diagonal was applied to participants firstly and according to the answers of the participants to the diagnostic test form, semi-structured interviews were carried out. Data collected form the diagnostic test form and the semi-structured interviews were analyzed with descriptive analysis. According to the results of the study, it is understood that the prospective teachers had difficulties with the diagonals of parallelogram, rhombus and deltoid. Moreover, it is also seen that the prospective teachers were inadequate to support their ideas with further explanations although they could answer correctly. İt is thought that the inadequacy of the prospective teachers stems from the inadequacy related to proof.DOI: http://dx.doi.org/10.22342/jme.8.2.4102.165-18
Pre-evaluation for the chemical substitution in a textile mill in Turkey
Kirlilik önleme çalışmalarında temel yaklaşımlardan birisi, kirletici özellikteki maddelerin daha az kirletici olanlar ile değiştirilmesidir. Bu çerçevede, biyolojik olarak kolay parçalanan maddelerin zor parçalananlara oranla uzun vadede daha az ekolojik problemlere neden olacağından hareketle, üretimde kullanılan kimyasal maddelerin biyodegradasyon özellikleri göz önüne alınması gereken önemli bilgilerden birisidir. Tekstil kimyasallarının toksik ve biyodegradasyon özellikleri konusunda yayınlanmış sınırlı sayıda çalışma bulunmaktadır. Kimyasalların biyodegradasyon potansiyellerini belirleme aşamasında, söz konusu kimyasala uygun yöntem seçilmesi önem arz etmektedir. Bu çalışmada, problemli kimyasalların ve alternatiflerinin biyodegradasyon potansiyellerini belirlemek amacıyla, OECD 302b (Zahn-Wellens) test metodu seçilmiştir. Testler, Türkiye’deki bir tekstil fabrikasında uygulanmakta olan reçetelerde kullanılan 2 adet kompleks yapıcı kimyasal madde (A ve B) ve kullanılma potansiyeli olan 1 adet kompleks yapıcı kimyasal maddenin (B*) biyodegradasyon potansiyellerini hem tek başlarına bulunmaları halinde var olan değerlerini doğrulamak, hem de birlikte kullanılmaları durumunda etkileşimlerini tespit etmek ve böylece, kimyasal değişikliğine karar verme aşamasında kullanmak amacıyla uygulanmıştır. Bu amaca yönelik olarak, kompleks oluşturan maddelerin farklı kombinasyonları ile kesikli reaktör deneyleri gerçekleştirilmiştir. Deneysel bulgular faktör analizi yöntemi ile istatistiksel analize tabi tutularak biyodegradasyon (bağlı değişken olarak) ve kompleks yapıcı madde konsantrasyonu (bağımsız değişken) arasındaki ilişki belirlenmiştir. Bu analizler, STATGRAPHIC istatistiksel yazılım programı kullanılarak yapılmıştır. Mümkün olabilecek kimyasal değişimine yönelik ön değerlendirme yapma amacıyla, doğrusal çoklu regresyon yöntemi ile matematiksel model oluşturulmuştur. Anahtar Kelimeler: Biyodegradasyon, doğrusal çoklu regresyon modeli, kimyasal değişimi, kirlilik önleme, kompleks yapıcı madde, tekstil endüstrisi.Substitution of less-pollutant chemicals for more-pollutant ones is a main focus for pollution prevention. In this respect, knowledge of the biodegradability of chemicals is one of the most important factors to be considered. In this study, to measure the biodegradability potential of the problematic chemicals (complexing agents A and B) used in a Turkish Textile Mill and their alternatives (complexing agent B*), OECD 302b (Zahn-Wellens) tests were conducted. Experiments were performed at different combinations of complexing agents using unacclimatized activated sludge bacteria as seed. The biodegradability tests results obtained for the combination of complexing agents A and B revealed that the biodegradability of complexing agent B (46-67%, depending on its concentration) is higher than that of complexing agent A (15-21%, depending on its concentration), when they are present alone. When they are together, the biodegradability varies between 36 and 45% depending on their existence levels. From these findings, the negative effect of having complexing agent A besides complexing agent B was apparent. The experimental results were also analyzed statistically by using factor analysis in order to clarify the relationship among the biodegradability and complexing agents. The following linear multiple regression model of the type was considered: Y = B1X1 + B2X2 + B12X12 + B11X11 + B22X22 Where; Y: Biodegradability of mixture of complexing agents A and B or A and B* (%); B1: Coefficient for the effect of complexing agent A; B2: Coefficient for the effect of complexing agent B or B*; B12: Coefficient for combined effects of complexing agents A & B or A & B*; B11: Coefficient for quadratic effect of complexing agent A; B22: Coefficient for quadratic effect of complexing agent B or B*; X1: Complexing agent A (mL/L); X2: Complexing agent B or B* (mL/L); X12 : Interaction term of X1 and X2 ; X11 : Quadratic term of complexing agent A; X22: Quadratic term of complexing agent B or B*. The form of the model obtained for the combination of complexing agents A and B is as follows; Y = -19.2502 X1 + 24.6749 X2 - 3.59036 X12 + 16.3031 X11 - 2.20622 X22 The biodegradability test results for combination of complexing agents A and B* revealed that the biodegradability of complexing agent B* is higher than that of B with a biodegradability varying between 79 and 89%, depending on the concentration. When together with the complexing agent A, the biodegradability varies between 58 and 69%. The model obtained is as follows; Y = -20.0037 X1 + 34.1467 X2 - 3.05722 X12 + 16.707 X11 - 3.20648 X22 The effects of complexing agent B and B* on the biodegradability is found to be both in the positive direction. That is, complexing agents B and B* strongly enhance the biodegradability characteristic of the mixes. When the complexing agents A and B, or A and B* (i.e. the term of X12) are present together, the total effect is inhibitory. According to the results of the models, there is an increase in the coefficient magnitude for the term X2 while using the complexing agent B* as compared to using the complexing agent B. This means that individual effect of complexing agent B* is higher than the individual effect of complexing agent B on biodegradability. According to the mix cases, the models show that there is also a small increase observed on term of X12 while using the complexing agent B*. The mix of complexing agent A and B has negative effects on biodegradability as understood from the negative sign of the coefficient. For the case of the complexing agent A and B* mix, this effect is again negative but it has a less magnitude value than mix of complexing agent A and B. By all things considered, complexing agent B* has better biodegradability characteristic than B. This behavior of B* is proven either by biodegradability tests of individual and mix concentrations and mathematical models set up by all experimental results. So, based on the results obtained in this study, if the mill considered to start using of this new chemical B* in the production line, a possible enhancement on biodegradability in wastewater would be achieved by the mill. Keywords: Biodegradability, linear multiple regression model, chemical substitution, pollution prevention, complexing agent, textile industry
Methyl 3-(4-bromophenyl)-2-(1H-indol-3-ylmethyl)-5-[1-(4-methoxyphenyl)-4-oxo-2-phenylazetidin-2-yl]-4-nitropyrrolidine-2-carboxylate
In the title compound, C37H33BrN4O6, the pyrrolidine ring adopts an envelope conformation. The β-lactam ring is planar and makes dihedral angles of 70.16 (13) and 28.32 (13)° with the phenyl and 4-methoxyphenyl rings, respectively. The molecular packing is stabilized by intramolecular C—H⋯O interactions and the crystal packing is determined by intermolecular N—H⋯O hydrogen bonds, and C—H⋯O and C—H⋯π interactions
Swift trust and commitment: the missing links for humanitarian supply chain coordination?
Coordination among actors in a humanitarian relief supply chain decides whether a relief operation can be or successful or not. In humanitarian supply chains, due to the urgency and importance of the situation combined with scarce resources, actors have to coordinate and trust each other in order to achieve joint goals. This paper investigated empirically the role of swift trust as mediating variable for achieving supply chain coordination. Based on commitment-trust theory we explore enablers of swift-trust and how swift trust translates into coordination through commitment. Based on a path analytic model we test data from the National Disaster Management Authority of India. Our study is the first testing commitment-trust theory (CTT) in the humanitarian context, highlighting the importance of swift trust and commitment for much thought after coordination. Furthermore, the study shows that information sharing and behavioral uncertainty reduction act as enablers for swift trust. The study findings offer practical guidance and suggest that swift trust is a missing link for the success of humanitarian supply chains
Slaughter weight rather than sex affects carcass cuts and tissue composition of Bisaro pigs
Carcass cuts and tissue composition were assessed in Bisaro pigs (n=64) from two sexes (31 gilts and 33 entire
males) reared until three target slaughter body-weights (BW) means: 17 kg, 32 kg, and 79 kg. Dressing percentage
and backfat thickness increased whereas carcass shrinkage decreased with increasing BW. Slaughter
weight affected most of the carcass cut proportions, except shoulder and thoracic regions. Bone proportion
decreased linearly with increasing slaughter BW, while intermuscular and subcutaneous adipose tissue depots
increased concomitantly. Slaughter weight increased the subcutaneous adipose tissue proportion but this impaired
intramuscular and intermuscular adipose tissues in the loin primal. The sex of the pigs minimally affected
the carcass composition, as only the belly weight and the subcutaneous adipose tissue proportions were greater
in gilts than in entire males. Light pigs regardless of sex are recommended to balance the trade-offs between
carcass cuts and their non-edible compositional outcomes.Work included in the Portuguese PRODER research Project
BISOPORC – Pork extensive production of Bísara breed, in two alternative
systems: fattening on concentrate vs chesnut, Project PRODER SI
I&DT Medida 4.1 “Cooperação para a Inovação”. The authors are
grateful to Laboratory of Carcass and Meat Quality of Agriculture
School of Polytechnic Institute of Bragança ‘Cantinho do Alfredo’. The
authors are members of the MARCARNE network, funded by CYTED
(ref. 116RT0503).info:eu-repo/semantics/publishedVersio
Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries
Abstract
Background
Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres.
Methods
This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries.
Results
In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia.
Conclusion
This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries
Institutional Information Manipulation and Individual Investors’ Disadvantages: A New Explanation for Momentum Reversal on the Chinese Stock Market
Bazı sinerjistik etkili insektisitlerin memeli sistemleri üzerinde toksik etkilerinin araştırılması
Bu tezin, veri tabanı üzerinden yayınlanma izni bulunmamaktadır. Yayınlanma izni olmayan tezlerin basılı kopyalarına Üniversite kütüphaneniz aracılığıyla (TÜBESS üzerinden) erişebilirsiniz.ABSTRACT INVESTIGATION OF TOXIC EFFECTS OF SOME INSECTICIDES WITH SINERGISTICAL EFFECT ON MAMMAL SYSTEMS KARABAY, N. Ülkü PhD in Biology Department Supervisor: Prof. Dr. M. Günnehir O?UZ October 2000, 121 Pages Although the pest control studies are recently performed by synergistically active pesticides, scientific contributions concerning these are also recent and very limited. The aim of this thesis was to determine the chromosomal and enzymatic effects of organochlorine insecticide imidacloprid, marketed and known as safe agent and organophosphate insecticide methamidophos on non-target species, when administered alone or in combination for synergistic effect. In this study, 10-12 week old, male (jn= 28) and female (n= 28) Wistar albino rats (100-150 g) were used. Animals of the control group were orally fed daily with a normal diet in standard laboratory chow, while animals of the treated group were fed with laboratory chow combined two different concentrations of each insecticides (50 and 100 ppm for imidacloprid; 2,5 and 5 ppm for methamidophos; 2,5 and 5 ppm for imidacloprid + methamidophos). Animals were treated with this insecticides for 15 weeks.VI At the end of the study, we found out that pesticide administration resulted in changes in organ weights. Moreover, these changes were not dose-dependent and they were specific to the pesticide class that was used. More lesions were determined in viscera when the insecticides were administered in combination when compared by their single ingestion. Chromosomal aberrations significantly increased when high concentrations of pesticides were used. An increased rate of these aberrations are considered as an indirect evidence of external pesticide treatment. No significant differences were observed in the percent of the cells with chromosome aberrations between the pesticide administered classes. However, evident differences were detected between all the pesticide administered groups vs. control group and between two concentrations of pesticide administered groups. Methamidophos, which is an organophosphate insecticide significantly inhibited liver cholinesterase activity. Furthermore, more inhibition was detected with respect to the methamidophos concentration used and this inhibition was found statistically significant especially in higher pesticide concentrations. Similarly, in the combination group, the effect of the organophosphate insecticide was dominant and concentration-dependent enzyme inhibition was observed only in methamidophos administrated group. This shows us the synergistic effect of the two insecticides. These results lead us to the conclusion that the synergistic effect of methamidophos and imidacloprid towards the target organisms may cause an unwanted increase in the potential damage to the non-target organisms. Keywords: Imidacloprid, methamidophos, chromosomal aberration, choline esterase enzyme activity, genotoxic effect.Ill ÖZET BAZI SİNERJİSTİK ETKİLİ İNSEKTİSİTLERİN MEMELİ SİSTEMLERİ ÜZERİNDE TOKSİK ETKİLERİNİN ARAŞTIRILMASI KARABAY, N. Ülkü Doktora Tezi, Biyoloji Anabilim Dalı Tez Yöneticisi: Prof. Dr. M. Günnehir OĞUZ Ekim 2000, 121 Sayfa Sinerjistik etkili pestisitlerle yapılan zararlı kontrol çalışmaları oldukça yemdir ve bu konuda yapılan bilimsel çalışmalar da sınırlı sayıdadır. Bu çalışmada, organofosforlu bir insektisit olan metamidofos ve piyasada güvenli bir pestisit olarak kullanılan ve organoklorlu bir insektisit olan imidaclopridin, hedef olmayan türler üzerindeki tek tek ve kombine şekilde kromozomal ve enzimatik etkilerini ortaya koymak ve bu şekilde sinerjistik etki amacıyla kombine kullanımın, tek tek kullanıma göre etkisini karşılaştırmak amaçlanmıştır. Çalışmada, 10-12 haftalık, ağırlıkları 120-150 g. arasında değişen Wistar Albino dişi («=28) ve erkek («=28) deney sıçanları kullanıldı. Her insektisitin 2 farklı konsantrasyonu (imidacloprid için 50 ve 100 ppm, metamidofos için 2,5 ve 5 ppm, imidacloprid + metamidofos kombinasyonu için 2,5 ve 5 ppm) ve kontrol grubu ile birlikte toplam 7 grup oluşturuldu. Hesaplanan konsantrasyonlarda hazırlanan insektisitler, standart laboratuarIV pellet yemlerine emdirilerek 15 hafta boyunca her gün aynı saatte sıçanlara oral olarak uygulandı. Kontrol gruba ise, standart laboratuar yemi verildi. Çalışma sonunda pestisit uygulamasının organ ağırlıklarında değişimlere yol açtığı belirlenmiş ve bu değişimlerin uygulanan doza bağlı olmayıp, pestisit grubuna özel olduğu sonucuna varılmıştır. Kombine insektisit kuUanımının, tek tek kullanıma göre iç organlarda daha fazla oranda lezyon oluşturduğu gözlenmiştir. Uygulanan pestisit gruplarının yüksek konsantrasyonlarında kromozomal aberasyonlar daha fazla oranda gözlenmiştir. Bu aberasyonların gözlenme oranındaki artış, dışarıdan pestisit muamelesi olduğunun indirekt kanıtıdır. Tüm uygulama gruplarıyla kontrol grubu arasında ve uygulama gruplarının iki farklı dozu arasında kromozom aberasyonlu hücre oram bakımından önemli farklılıklar belirlendiği halde, uygulanan pestisit sınıfları arasında önemli bir farklılık kaydedilememiştir. Organofosforlu bir insektisit olan metamidofosun, karaciğer kolinesteraz enzim aktivitesini inhibe ettiği belirlenmiştir ve bu inhibisyon uygulanan metamidofos konsantrasyonuna bağlı olarak artmaktadır. Bu artış özellikle yüksek konsantrasyonlarda belirgindir ve kontrol gruplarına göre istatistiksel olarak anlamlı bir farklılık göstermektedir. Kombine grupta da yine organofosforlu insektisitin etkisi baskındır ve konsantrasyondaki artışla birlikte enzim inhibisyonu yalnız metamidofos uygulanmış gruba göre daha fazla artmaktadır. Bu durum iki insektisitin sinerjistik olarak etkiyi arttırdığını göstermektedir. Elde edilen sonuçlar, hedef organizmalara karşı oluşması istenen sinerjistik etkinin, hedef olmayan organizmalara karşı oluşabilecek potansiyel zararları daha da arttırabileceğini göstermektedir
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