Experimental comparison of combine performance with two harvesting methods: stripper header and conventional header

Residual straw status on the field after harvesting was one of the important obstacles in using stripper header in Iran. In this work, combine performance studied with two type headers, conventional and stripper in wheat farm. Residual stems after harvesting collected, baled, and two methods were compared. The results showed that fuel consumption in the stripper header was 5.68 L/ha less than the conventional header. Combines with stripper header harvested 1500 m2 more than the conventional header in each hour. Stripper header in comparison with the conventional had 21% harvesting efficiency and 840 kg/h field performance which harvested more wheat. Harvesting time and fuel consumption for straw harvesting operation in the harvested field with stripper header were 1.5 minutes and 23.53 L respectively, which were higher than conventional header. However, with stripper method, 2040 kg/ha more straw were collected compared to conventional method. Stripper field status after harvesting operations was far cleaner and more ready for next operation than the other

Analysis and comparison of wheat losses in two harvesting methods

Wheat losses in John Deere 955 combine was compared between stripper header and conventional header.  Tests were conducted in a wheat field.  At first for comparison, the optimum working condition was obtained for both type of headers and then other parameters are compared. Results showed that the optimum working condition of combine with a second gear and mediate engine speed for stripper header was obtained with 75 cm for hood distance, 60 cm for header distance and 760 rmin-1 for rotor speeds.  In stripper header, the total loss of different parts of combine was under 3.5%, although these losses in conventional header reached up to 6.5% which was the highest loss for headers.  Number and weight of lost cluster in harvesting with stripper header was much less than conventional header. Keywords: wheat, stripper header, conventional header, rotor speed, los

Role of the unique N-terminal domain of CtBP2 in determining the subcellular localisation of CtBP family proteins

BACKGROUND: CtBP1 and CtBP2 are transcriptional co-repressors that modulate the activity of a large number of transcriptional repressors via the recruitment of chromatin modifiers. Many CtBP-regulated proteins are involved in pathways associated with tumorigenesis, including TGF-beta and Wnt signalling pathways and cell cycle regulators such as RB/p130 and HDM2, as well as adenovirus E1A. CtBP1 and CtBP2 are highly similar proteins, although evidence is emerging that their activity can be differentially regulated, particularly through the control of their subcellular localisation. CtBP2s from diverse species contain a unique N-terminus, absent in CtBP1 that plays a key role in controlling the nuclear-cytoplasmic distribution of the protein.RESULTS: Here we show that amino acids (a.a.) 4-14 of CtBP2 direct CtBP2 into an almost exclusively nuclear distribution in cell lines of diverse origins. Whilst this sequence contains similarity to known nuclear localisation motifs, it cannot drive nuclear localisation of a heterologous protein, but rather has been shown to function as a p300 acetyltransferase-dependent nuclear retention sequence. Here we define the region of CtBP2 required to co-operate with a.a. 4-14 to promote CtBP2 nuclear accumulation as being within a.a. 1-119. In addition, we show that a.a. 120-445 of CtBP2 can also promote CtBP2 nuclear accumulation, independently of a.a. 4-14. Finally, CtBP1 and CtBP2 can form heterodimers, and we show that the interaction with CtBP2 is one mechanism whereby CtBP1 can be recruited to the nucleus.CONCLUSION: Together, these findings represent key distinctions in the regulation of the functions of CtBP family members that may have important implications as to their roles in development, and cell differentiation and survival.<br/

Temperature Distribution Simulation of the Human Eye Exposed to Laser Radiation

Introduction: Human eye is a sensitive part of human body with no direct protection and due to its lack of protection against the external heat waves, studying the temperature distribution of heat waves on the human eye is of utmost importance. Various lasers are widely used in medical applications such as eye surgeries. The most significant issue in the eye surgeries with laser is estimation of temperature distribution and its increase in eye tissues due to the laser radiation intensity. Experimental and invasive methods to measure the eye temperature usually have high risks.Methods: In this paper, human eye has been modeled through studying the temperature distribution of three different laser radiations, using the finite element method. We simulated human eye under 1064 nm Neodymium-Doped Yttrium Aluminium Garnet (Nd: YAG) laser, 193 nm argon fluoride (ArF) excimer laser, and 1340 nm Neodymium doped Yttrium Aluminum Perovskite (Nd: YAP) laser radiation.Results: The results show that these radiations cause temperature rise in retina, lens and cornea region, which will in turn causes serious damages to the eye tissues.Conclusion: This simulation can be a useful tool to study and predict the temperature distribution in laser radiation on the human eye and evaluate the risk involved in using laser to perform surgery

Three essays on the economics of science policy: the impact of funding, collaboration and research chairs

RÉSUMÉ : Cette thèse étudie les déterminants qui influencent le nombre de citations, l'effet d'avoir une collaboration de recherche avec les scientifiques les mieux financés sur la productivité scientifique, et l'effet d’être titulaire d'une chaire de recherche sur la productivité scientifique. En supposant que le nombre de citations est une bonne mesure de l'impact de la recherche et, à son tour, d’un certain type de qualité, nous avons montré que le nombre d'articles et la visibilité d'un chercheur, le facteur d’impact de la revue, la taille de l’équipe de recherche, et le cadre institutionnel de l'université (effet fixe) sont les déterminants importants du nombre de citations. Cependant, nous avons constaté qu'il n'y a pas d'effet significatif du financement public ni du genre dans la plupart des domaines examinés. Nous avons également développé un modèle théorique et proposé quelques hypothèses sur l'effet de la collaboration avec les scientifiques les mieux financés sur la productivité scientifique. Ce modèle a ensuite permis de valider les hypothèses à l’aide d’une analyse empirique et a montré que cette collaboration a un effet positif sur la productivité scientifique. Cet effet significatif peut exister à travers différents canaux: le transfert de connaissances tacites, davantage de publications scientifiques, des économies d'échelle dans la production de connaissances dues à de meilleurs équipements de recherche et un réseau de recherche élargi. Les résultats ont également vérifié l'effet positif du financement, l'effet positif du réseau (mesuré par le nombre de co-auteurs), l'effet en forme de U-inversé de l'âge, et le plus petit nombre de publications par les femmes par rapport aux hommes. Enfin, nous avons fait une distinction entre les différents attributs des chaires de recherche et de leur effet sur la productivité scientifique. Une des questions importantes est de savoir si une chaire de recherche a encore une meilleure performance scientifique (par rapport aux non-titulaires) après avoir contrôlé par les fonds de recherche disponibles aux chercheurs. Pour étudier cela, nous avons utilisé une technique d'appariement pour identifier les paires de scientifiques (des titulaires et des non-titulaires de chaires) de même genre, financement et domaine de recherche. Après cette correspondance, nous avons constaté que l'effet du programme des chaires de recherche du Canada sur la productivité scientifique reste significatif et positif alors que l'effet des chaires industrielles et les titulaires de chaires nommés par les conseils canadiens subventionnaires fédéraux (CRSNG et IRSC) deviennent non significatif. Ce constat met en évidence l'efficacité de notre méthode de technique d'appariement car avant l’appariement, tout type de chaire a un effet positif et significatif sur la productivité scientifique. Ce constat met en évidence les attributs spéciaux du programme de chaires de recherche du Canada, qui sont différents des autres programmes de chaire. Ces attributs spécifiques peuvent pousser de manière significative la productivité scientifique. Entre autres, les chaires de recherche du Canada sont généralement associés à un certain degré de prestige et confèrent une plus grande visibilité pour recruter des étudiants talentueux ou pour développer une collaboration de recherche avec des scientifiques de haut niveau dans le domaine. Le fait que d'autres types de chaires de recherche, une fois appariés avec des scientifiques équivalents, n’ont pas d’impact sur la production scientifique en termes de quantité, ne signifie pas que ces titulaires de chaire sont des scientifiques de moindre envergure, mais qu'ils consacrent une partie de leur temps à d'autres efforts de nature plus pratique ou ayant un impact sociétal différent. Ainsi les universités maintiennent un équilibre entre la poursuite de la connaissance scientifique pure et son application à des avantages socioéconomiques. En étudiant uniquement les articles scientifiques, il nous manque toutefois beaucoup d’information quant au rôle des professeurs d'université. Bien que non trivial, la recherche future devrait viser à ratisser plus large sur les réalisations, les résultats et les impacts de la recherche universitaire.----------ABSTRACT : This thesis studies the determinants that influence the number of citations, the effect of having a research collaboration with top-funded scientists on scientific productivity, and the effect of holding a research chair on scientific productivity. Based on a review study by Bornmann and Daniel (2008), one can argue that non-scientific factors determining the decision to cite do not significantly alter the role of citation as a measure of research impact. Assuming that the number of citations is a good measure for research impact and, in turn, for a certain kind of quality, we showed that the number of articles and the visibility of a researcher, the impact factor of the journal,the size of the research team, and the institutional setting of the university are the important determinants of citation counts. However, we have found that there is no significant effect of public funding and gender in most of the domains examined. The point that funding amount is not a significant determinant of citation counts does not necessarily contradict the positive effect of funding on scientific productivity. We also developed a theoretical model and proposed some hypotheses about the effect of collaboration with top-funded scientists on scientific productivity. We then validated the hypotheses with empirical analysis and showed that such collaboration has a positive effect on scientific productivity. This significant effect may exist through different channels: transfer of tacit knowledge, more scientific publications, economy of scale in knowledge production because of better research equipment, and expanded research network. The results also verified the positive effect of funding, the positive effect of networking (measured by number of co-authors), the inverted U-shaped effect of age, and the fewer number of publications by women compared to men. Finally, we made a distinction between different attributes of research chairs and their effect on scientific productivity. One of the important questions is to find out whether a research chair still has better scientific productivity (compared to non-chair holders) after controlling for the research funds available to the researchers. To investigate that question, we employed a matching technique to identify pairs of scientists (chair and non-chair holders) of the same gender, funding and research field. After such matching, we found that the effect of the Canada research chair program on scientific productivity remains significant and positive, while the effect of industrial chairs and the chairs appointed by the Canadian federal granting councils (NSERC and CIHR) become nonsignificant. This finding highlights the effectiveness of our matching technique methodology; because before matching, holding any type of chair had a positive and significant effect on scientific productivity. This finding highlights the special attributes of the Canada research chair program, which are not replicated in other chairs. Those specific attributes may significantly push scientific productivity. For example, Canada research chairs are generally associated with some degree of prestige or higher visibility to recruit talented students or to have research collaboration with top scientists in the field. In addition, the Canada research chair program has a firm and efficient method of allocation (which is explained in the thesis). This approach institutionally synchronizes different chairs in universities and research fields. The fact that other types of research chairs, once matched with equivalent scientists, do not have an impact on scientific output in terms of quantity does not imply that these chair holders are lesser scientists, but that they are devoting part of their time to other endeavours of a more practical nature. Hence universities are maintaining a balance between the pursuit of pure scientific knowledge and its application to socioeconomic benefits. By solely studying scientific articles, we are missing a great deal of the university professors’ activities. Although not trivial, future research should aim to cast a wider net on outputs, outcomes and impacts of university research

Application of deep learning and machine learning workflows for field-scale phenotyping

Tassel is the male inflorescences organ of the maize plant that develops atop the plant. Coarse features of tassels, including shape and size, can influence shedding pollen, fertilization, and subsequently grain yield. Therefore, understanding tassel dynamics and characteristics as well as how it evolves during the plant growth can help the plant scientist community to increase the grain yield as a final goal. To do so, first, tassels were investigated in one time points. The tassels were cut in the field and their images were captured in a lightbox. Coarse features were measured using novel image processing approaches. 351 tassels with different genotypes were used for the experiment. Tassel length, first lowest branch length, and angle as well as central spike length were measured by applying image processing and machine learning techniques. Tassels were also classified to open and close structures to obtain accurate predictions for the traits. The results show that R2 values for the tassel length and central spike length were 0.92 and 0.80, respectively. In addition, the R2 values for the first lowest branch length and angle were 0.63 and 0.91, respectively. The R2 values for the first lowest branch length was low compared to others because locating the first lowest branch point and its corresponding branch tip was hard due to branches occlusion. This study was done to create a robust algorithm for tassel phenotyping. Challenges were figured out for better tassel phenotyping in the field. Then, we looked at a diverse panel in the field, using stationary cameras to capture 6 tassels every 10 minutes for 8 hours per day during a month. Traditional approaches for phenotyping anthesis progression are time-consuming, subjective, and labor-intensive and are thus impractical for phenotyping large populations in multiple environments. In this work, we utilize a high throughput phenotyping approach that is based on extracting time-lapse information of anthesis progress from digital cameras. The major challenge is identifying the region of the interest (i.e. location of tassels in the imaging window) in the acquired images. Camera drift, different types of weather, including fog, rain, clouds, and sun and additionally, occlusion of tassels by other tassels or leaves complicated this problem. We discussed the associated challenges for object detection and localization under noisy conditions. In addition, a framework was developed to utilize Amazon Mechanical Turk to allow turkers to annotate the images and evaluate them to create an object detection dataset. Finally, we illustrated a promising deep-learning approach to tassel recognition and localization that is based on Faster-RCNN which has shown the strong capability for detection and localization. This method was improved using a boosting method to improve the dataset. This approach is able to reliably identify a diverse set of tassel morphologies with the mAP of 0.81. Tassel flowering pattern is the most important and complex trait. Tassel maize as a male structure is responsible to produce pollen for the silk as a female organ on the same plant. The amount of pollen and shedding time is important for the breeders as well as the biologists. This study introduced an automated end-to-end pipeline by coupling various deep learning, machine learning and image processing approaches. Inbred lines from both SAM and NAM panels were grown at Curtiss farm at Iowa State University, Ames, IA. A stationary camera was installed for every two plants. Tassels architecture, weather type, tassels and camera movements are the most important challenges of the research. To address these issues, deep learning algorithms were utilized. Tassel detection, classification, and segmentation. In addition, advanced image processing approaches were used to crop the tassel main spike and track the during tassel evolution. The results showed that deep learning is a powerful tool to detect, classify and segment the tassels. The mAP for the tassel detection was 0.91. The F1-score obtained for the tassel classification was 0.93. In addition, the accuracy of semantic segmentation for creating a binary image from the RGB tassel images was 0.95. The width of the flowering was obtained using graph theory in image processing and the time and location of the flowering can be obtained from the width data over the main spike branch. In addition to tassel structures, crop growth simulation models can help farmers and breeders predict crop performance, and in maize, Leaf Appearance Rate (LAR) is an important parameter used in crop performance simulation models such as APSIM. Since breeders and biologists would like to minimize human involvement in monitoring LAR, this trait can be monitored by applying a high-throughput phenotyping system. Engineers have entered the picture in collaboration with plant scientists to establish different and robust phenotyping methods, and in this study, maize leaf appearance rate was investigated using high-throughput phenotyping approaches. We developed an imaging system for automatically capturing a time-series of images of maize plants under field conditions, with 380 RGB cameras were used to capture images from 380 rows. There were 6 plants with the same genotype in each row that had different genotypes differed row-by-row, and the images were taken for 9 hours daily at 20- minute intervals for more than one month during a growing season. An end-to-end deep learning method was then used to count the numbers of leaves in the images. The dataset for the deep learning algorithm, obtained using the Amazon Mechanical Turk platform, was created by one expert turker along with a well-trained turker. Results demonstrated that an end-to-end model with training based on the expert turker dataset performed very well, handling variation in images that included leaf occlusions and weather type. The R2 between the ground truth obtained by the expert turker and predicted values was approximately 0.73, 0.74, and 0.95 for three testing cameras. The model\u27s prediction performance demonstrated that the number of leaves increase with different slopes for different genotypes. The data can be used for further genotypic analysis

MicroRNA Control of Invasion and Metastasis Pathways

Despite recent advances, cancer remains a leading cause of death worldwide. In developed countries, the incidence of colorectal and breast cancer has been stable, but no improvement in prognosis has been observed if the patient presents with metastases at diagnosis. This fact highlights the importance of therapeutic approaches targeting cellular invasion and metastasis programs as the next step in cancer treatment. During carcinoma progression a process called epithelial–mesenchymal transition (EMT) results in enhanced invasion and motility which is directly linked with loss of epithelial polarity and epithelial junctions, migration permissive cytoskeleton alterations, and the acquisition of mesenchymal properties. The recent discovery of microRNAs (miRNAs) controlling key cellular pathways has opened a new era in understanding how EMT pathways are modulated. In this review, we classify EMT regulating proteins according to their cellular localization (membrane, cytoplasmic, and nuclear), and summarize the current knowledge on how they are controlled by miRNAs and propose potential miRNAs for the transcripts that may control their expression