70 research outputs found
Development and Evaluation of a Semi-automatic Cucumber Seed Extractor
IntroductionAccording to FAO, gherkin and cucumber have been cultivated in about 2.23 million hectares of farmlands around the globe, and about 78000 hectares of Iran agricultural fields have been devoted to gherkin and cucumber cultivation. However, large amounts of the cucumber seeds required in Iran have been imported from abroad. Fortunately, some Iranian agricultural companies have been focused on seed production recently. Therefore, there is an opportunity to develop seed production equipment such as seed extracting machines.There are two types of cucumber seed extractors: bulk seed extractor and single fruit extractor. The bulk seed extractor is suitable for extraction of large amounts of seed on the farm, while the single fruit extractor is suitable where seed production is limited to greenhouse seed-producing facilities which are mostly used for controlled pollination of the crop.Due to the high price of imported seed extractors, especially after increasing the price of foreign currencies, production of these machines within the country is economically rational; therefore, the aim of this research is to develop and evaluate a single fruit cucumber seed extractor for small and medium-size seed-producing greenhouses.Materials and MethodsThe cucumber seed extractor was designed semi-automatically. The criteria for designing the machine were as follows: 1- usage of the single fruit seed extraction method, 2- the possibility of simultaneous usage of two operators, 3- automatic discharge of the extracted seeds, 4- the possibility of the height variation of the machine, 5- the possibility of the emergency shutdown of the machine, 6- the possibility of the angular velocity variation of the machine helix.The working element of the machine was the rotating helix that can extract the fruit seeds and leave the fruit's outer skin mostly intact for easy disposal of fruit remains from the greenhouse. A 1 hp, 3 phase electric motor was used to drive the machine via the belt and pulley transmission system. For the smooth start and stop of the machine, and the possibility of angular velocity variation of the machine helixes, an electronic driver was used for the motor.To design the machine helix, the dimensions of the examined cucumber were measured first (i.e., cucumber length and diameter); then, according to the physical and mechanical properties of the fruit, the prime mover and transmission system of the machine was designed. Finally, the fabricated machine was evaluated using some mechanization criteria.Results and DiscussionSome of the results are as follows:The total torque required to drive the machine was 3.394Nm.The electric motor power should be higher than 0.284hp; furthermore, in order to have a wider angular velocity span for the rotating shaft, a 1hp electric motor was installed on the machine.The diameter of the rotating shaft was calculated to be 15mm.The seed extracting machine could be used instead of 15 workers of the manual seed extraction method.The rate of seed extraction using the machine was 30781 kg ha-1.The efficiency of seed extraction using the machine was similar to that of the manual method.The emergence percentage of seeds obtained by the machine was similar to that of the manual method.The amount of crop calculated from the concept of economical break-even point was 7 tons.ConclusionIn this study, an apparatus for mechanized extraction of cucumber seed was designed, fabricated and evaluated. The working element of the machine is the extractor helix that is rotated via the belt and pulley transmission system, which is activated using a 1 hp, 3 phase electric motor. For smooth start and stop of the motor, as well as the possibility of angular velocity variation of the machine helix, the motor was equipped with an electronic driver. Utilizing an emergency shutdown switch, the machine can be protected from unforeseen emergency situations. After using the machine for 6 months, it was recognized that strengthening the extractor helixes was necessary. According to the results of this study, using the machine led to 15 person reduction in the labor needs of the manual cucumber seed extraction method. Moreover, the amount of crop calculated from the economical break-even point was 7.7 tons
Effect of different physio-chemical factors on sex expression and fruit yield in green-house cucumber
Male flower expression is considered an important aim in greenhouse cucumber breeding for creating paternal lines as a base for hybrid progeny. The study was carried out to evaluate the effects of different treatments on sex expression and fruit yield of cucumber in two different season (autumn-winter and spring-summer), in particular this research focuses on the influence of 1) usage of two chemical agents: silver thiosulphate [Ag(S2O3)2-3] and silver nitrate (AgNO3) at different concentration, respectively 200 and 500 ppm and 100, 200 and 300 ppm 2) plant development stages at the moment of the treatment (5, 10, and 15-leaf growth stages) and 3) application of single or double sprayings. Analysis of variance showed that season, chemical applications and number of spaying had significant effect on the induction of a higher number of male flowers. A positive significant effect of season suggested that longer days and higher temperature promote the formation of male flowers in cucumber. This study showed that male flower production was induced by all concentrations of silver ions, especially high concentrations. Important traits related to change of sex expression such as the number of days to male flowering and the number of male flowers are more affected by different interactions of studied factors in contrast to vegetative and yield related traits. Also, the quadruple interaction effects indicated that silver ion could change sex expression at higher temperatures and longer days (second season in summer) with high concentration when applied in 15 leaf stage for AgNO3 and 5 and 15 leaf growth stage for Ag(S2O3)2-3 with double spraying. Consequently, female lines can be induced to male flowering with silver ions, thus increasing the feasibility of large scale seed production of gynoecious × gynoecious cucumber hybrid
Inverse problem of photoelastic fringe mapping using neural networks
This paper presents an enhanced technique for inverse analysis of photoelastic fringes using neural networks to determine the applied load. The technique may be useful in whole-field analysis of photoelastic images obtained due to external loading, which may find application in a variety of specialized areas including robotics and biomedical engineering. The presented technique is easy to implement, does not require much computation and can cope well within slight experimental variations. The technique requires image acquisition, filtering and data extraction, which is then fed to the neural network to provide load as output. This technique can be efficiently implemented for determining the applied load in applications where repeated loading is one of the main considerations. The results presented in this paper demonstrate the novelty of this technique to solve the inverse problem from direct image data. It has been shown that the presented technique offers better result for the inverse photoelastic problems than previously published works
Gold nanoprisms as a hybrid in vivo cancer theranostic platform for in situ photoacoustic imaging, angiography, and localized hyperthermia
The development of high-resolution nanosized photoacoustic contrast agents is an exciting yet challenging technological advance. Herein, antibody (breast cancer-associated antigen 1 (Brcaa1) monoclonal antibody)- and peptide (RGD)-functionalized gold nanoprisms (AuNprs) were used as a combinatorial methodology for in situ photoacoustic imaging, angiography, and localized hyperthermia using orthotopic and subcutaneous murine gastric carcinoma models. RGD-conjugated PEGylated AuNprs are available for tumor angiography, and Brcaa1 monoclonal antibody-conjugated PEGylated AuNprs are used for targeting and for in situ imaging of gastric carcinoma in orthotopic tumor models. In situ photoacoustic imaging allowed for anatomical and functional imaging at the tumor site. In vivo tumor angiography imaging showed enhancement of the photoacoustic signal in a time-dependent manner. Furthermore, photoacoustic imaging demonstrated that tumor vessels were clearly damaged after localized hyperthermia. This is the first proof-of-concept using two AuNprs probes as highly sensitive contrasts and therapeutic agents for in situ tumor detection and inhibition. These smart antibody/peptide AuNprs can be used as an efficient nanotheranostic platform for in vivo tumor detection with high sensitivity, as well as for tumor targeting therapy, which, with a single-dose injection, results in tumor size reduction and increases mice survival after localized hyperthermia treatment.National Basic Research Program of China (No. 2015CB931802)National Natural Science Foundation (China) (Nos. 81225010, 81327002, 31170961, 20771075, and 20803040)National High-Tech R&D Plan of China (No. 2014AA020700)Shanghai Science and Technology Fund (Nos. 13NM1401500 and 15DZ2252000
Toxicity and cellular uptake of gold nanoparticles: what we have learned so far?
Gold nanoparticles have attracted enormous scientific and technological interest due to their ease of synthesis, chemical stability, and unique optical properties. Proof-of-concept studies demonstrate their biomedical applications in chemical sensing, biological imaging, drug delivery, and cancer treatment. Knowledge about their potential toxicity and health impact is essential before these nanomaterials can be used in real clinical settings. Furthermore, the underlying interactions of these nanomaterials with physiological fluids is a key feature of understanding their biological impact, and these interactions can perhaps be exploited to mitigate unwanted toxic effects. In this Perspective we discuss recent results that address the toxicity of gold nanoparticles both in vitro and in vivo, and we provide some experimental recommendations for future research at the interface of nanotechnology and biological systems
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Predicting breast cancer response to neoadjuvant treatment using multi-feature MRI: results from the I-SPY 2 TRIAL.
Dynamic contrast-enhanced (DCE) MRI provides both morphological and functional information regarding breast tumor response to neoadjuvant chemotherapy (NAC). The purpose of this retrospective study is to test if prediction models combining multiple MRI features outperform models with single features. Four features were quantitatively calculated in each MRI exam: functional tumor volume, longest diameter, sphericity, and contralateral background parenchymal enhancement. Logistic regression analysis was used to study the relationship between MRI variables and pathologic complete response (pCR). Predictive performance was estimated using the area under the receiver operating characteristic curve (AUC). The full cohort was stratified by hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) status (positive or negative). A total of 384 patients (median age: 49 y/o) were included. Results showed analysis with combined features achieved higher AUCs than analysis with any feature alone. AUCs estimated for the combined versus highest AUCs among single features were 0.81 (95% confidence interval [CI]: 0.76, 0.86) versus 0.79 (95% CI: 0.73, 0.85) in the full cohort, 0.83 (95% CI: 0.77, 0.92) versus 0.73 (95% CI: 0.61, 0.84) in HR-positive/HER2-negative, 0.88 (95% CI: 0.79, 0.97) versus 0.78 (95% CI: 0.63, 0.89) in HR-positive/HER2-positive, 0.83 (95% CI not available) versus 0.75 (95% CI: 0.46, 0.81) in HR-negative/HER2-positive, and 0.82 (95% CI: 0.74, 0.91) versus 0.75 (95% CI: 0.64, 0.83) in triple negatives. Multi-feature MRI analysis improved pCR prediction over analysis of any individual feature that we examined. Additionally, the improvements in prediction were more notable when analysis was conducted according to cancer subtype
Crown Ether Nanovesicles (Crownsomes) Repositioned Phenytoin for Healing of Corneal Ulcers
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