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As plant diseases could cause agricultural production and economic loses, there is a need of fast and effective plant disease detection and assessment methods. Non-destructive methods have gained popularity among these methods as they do not affect plant growth while examining plant health conditions. Not only plant diseases can be detected but also production can be improved with proper quality controls. Hyperspectral imaging is one of the non-destructive examination techniques which have been widely applied in agriculture. Hyperspectral image analysis has been applied to different problems including plant disease detection and assessments. It provides not only spatial image but also spectral information of the observed object. This research has aimed to compare two hyperspectral image analysis methods: stepwise discriminant analysis (SDA) and spectral angle mapper (SAM) and the proposed Simple Slope Measure (SSM) method in strawberry foliage Anthracnose assessment. Anthracnose is one of the most devastating diseases for strawberries. Anthracnose disease can affect the whole plant and may result in 100 percent fruit loss from crown and fruit rot. Hence, an early detection of the Anthracnose disease will be beneficial to ensure production and quality of strawberries. This research has shown that the three different Anthracnose infection status (healthy, incubation and symptomatic) could be separated by the methods examined. The performance of these disease assessment models were evaluated and compared. The examination outcomes prove the feasibility to assess strawberry foliage Anthracnose nondestructively and as early as the symptoms not visible to naked eyes. As soon as early detections of the Anthracnose disease are achievable in the strawberry field, the damage to strawberry production due to the spread of Anthracnose disease could be reduced.

In plant factories, plants are usually cultivated in nutrient solution under a controllable environment. Plant quality and growth are closely monitored and precisely controlled. For plant growth evaluation, plant weight is an important and commonly used indicator. Traditional plant weight measurements are destructive and laborious. In order to measure and record the plant weight during plant growth, an automated measurement system was designed and developed herein. The weight measurement system comprises a weight measurement device and an imaging system. The weight measurement device consists of a top disk, a bottom disk, a plant holder and a load cell. The load cell with a resolution of 0.1 g converts the plant weight on the plant holder disk to an analogue electrical signal for a precise measurement. The top disk and bottom disk are designed to be durable for different plant sizes, so plant weight can be measured continuously throughout the whole growth period, without hindering plant growth. The results show that plant weights measured by the weight measurement device are highly correlated with the weights estimated by the stereo-vision imaging system; hence, plant weight can be measured by either method. The weight growth of selected vegetables growing in the National Taiwan University plant factory were monitored and measured using our automated plant growth weight measurement system. The experimental results demonstrate the functionality, stability and durability of this system. The information gathered by this weight system can be valuable and beneficial for hydroponic plants monitoring research and agricultural research applications.

Hundreds of therapeutic monoclonal antibodies (mAbs) are currently in development, and many companies have multiple antibodies in their pipelines. Current methodology used in recovery processes for these molecules are reviewed here. Basic unit operations such as harvest, Protein A affinity chromatography, and additional polishing steps are surveyed. Alternative processes such as flocculation, precipitation, and membrane chromatography are discussed. We also cover platform approaches to purification methods development, use of high throughput screening methods, and offer a view on future developments in purification methodology as applied to mAbs.

Between July 2004 and January 2005, high mortalities (up to 80–100%) were frequently encountered in postlarvae of Macrobrachium rosenbergii in southern Taiwan. Pathologically, eosinophilic intranuclear inclusion bodies (INIs) were found only in the hepatopancreatic tubular epithelial cells of the infected postlarvae from hatchery farms. No lesions could be detected in tissue of ectodermal or mesodermal origin. Interestingly, different lesions were found in sub-adults collected from a grow-out farm. Atrophic changes in abdominal muscles from the fourth to sixth segment and tail fan, associated with a reddish discoloration, were prominent features in these shrimp, but there was no unusual mortality or INI formation. In PCR assays for the detection of infectious hypodermal and haematopoietic necrosis virus (IHHNV), hepatopancreatic parvovirus (HPV), white spot syndrome virus (WSSV), Taura syndrome virus (TSV), yellowhead virus (YHV), M. rosenbergii nodavirus (MrNV) and extra small virus (XSV), only an expected 389-bp product, specific for the IHHNV nonstructural protein gene, was obtained from all postlarvae and sub-adults examined. Positive reactions to in situ hybridization, using a DIG-labelled DNA probe, further confirmed IHHNV as the causative agent. In a comparison of our strains with Taiwanese (GenBank accession no. AY 355306 and AY 355308 ) and American strains (GenBank accession no. AF218266 and AF273215 ), nucleotide sequence identities were up to 99.7%. This is the first report concerning natural infection of IHHNV in postlarvae and sub-adults of M. rosenbergii .

Utilization of male sterility is a key method for producing crossbred Chinese cabbage (Brassica rapa L. ssp. pekinensis (Lour.) Olsson. In this study, suppression subtractive hybridization (SSH) was used to construct sterility and fertility cDNA libraries, which included differentially, expressed clones between fertile and sterile buds of the A/B line ‘AB01’. The positive clones were randomly selected by polymerase chain reaction amplification (PCR) and 25 high quality sequences (22 from the fertile-tester library and three from the sterile-tester libraries) were generated. The fragment lengths varied from 77 to 469 bp. Differential expression patterns between fertile and sterile buds were selected and verified using five expressed sequence tags (ESTs). Results indicated that, three ESTs were expressed only in fertile buds and two ESTs were down-regulated in sterile buds. According to the Basic Local Alignment Search Tool (BLAST) screening and functional annotation, the 25 ESTs were homologous to known sequences deposited in National Center for Biotechnology Information (NCBI). These genes had homology to known proteins such as flowers/buds development proteins, metabolic-related proteins, cell structure proteins, cell growth/division proteins and secondary metabolic-related proteins. The results suggested that, these proteins played a critical role in nuclear male sterility progression of genic multiple-allele inherited male-sterility in Chinese cabbage.Key words: Chinese cabbage, male sterility, suppression subtractive hybridization (SSH), expressed sequence tags (ESTs).

Cation exchange chromatography using conventional resins, having either diffusive or perfusive flow paths, operated in bind-elute mode has been commonly employed in monoclonal antibody (MAb) purification processes. In this study, the performance of diffusive and perfusive cation exchange resins (SP-Sepharose FF (SPSFF) and Poros 50HS) and a convective cation exchange membrane (Mustang S) and monolith (SO(3) Monolith) were compared. All matrices were utilized in an isocratic state under typical binding conditions with an antibody load of up to 1000 g/L of chromatographic matrix. The dynamic binding capacity of the cation exchange resins is typically below 100 g/L resin, so they were loaded beyond the point of anticipated MAb break through. All of the matrices performed similarly in that they effectively retained host cell protein and DNA during the loading and wash steps, while antibody flowed through each matrix after its dynamic binding capacity was reached. The matrices differed, though, in that conventional diffusive and perfusive chromatographic resins (SPSFF and Poros 50HS) demonstrated a higher binding capacity for high molecular weight species (HMW) than convective flow matrices (membrane and monolith); Poros 50HS displayed the highest HMW binding capacity. Further exploration of the conventional chromatographic resins in an isocratic overloaded mode demonstrated that the impurity binding capacity was well maintained on Poros 50HS, but not on SPSFF, when the operating flow rate was as high as 36 column volumes per hour. Host cell protein and HMW removal by Poros 50HS was affected by altering the loading conductivity. A higher percentage of host cell protein removal was achieved at a low conductivity of 3 mS/cm. HMW binding capacity was optimized at 5 mS/cm. Our data from runs on Poros 50HS resin also showed that leached protein A and cell culture additive such as gentamicin were able to be removed under the isocratic overloaded condition. Lastly, a MAb purification process employing protein A affinity chromatography, isocratic overloaded cation exchange chromatography using Poros 50HS and anion exchange chromatography using QSFF in flow through mode was compared with the MAb's commercial manufacturing process, which consisted of protein A affinity chromatography, cation exchange chromatography using SPSFF in bind-elute mode and anion exchange chromatography using QSFF in flow through mode. Comparable step yield and impurity clearance were obtained by the two processes.

Recombinant human zona pellucida (rhZP) proteins (minus the N-terminal leader and the C-terminal transmembrane-like domain) were expressed in four different expression systems: bacteria, yeast, insect cells, and Chinese Hamster Ovary (CHO) cells. The recombinant proteins in each system were engineered with a C-terminal six histidine (His6) segment that was used to purify the proteins by metal affinity [either nickel (Ni) or cobalt (Co)] column chromatography. Each of the rhZP proteins was a candidate antigen as an immunocontraceptive vaccine. However, the rhZP proteins produced in bacteria, yeast and insect cell culture could only be purified after being solubilized by strong denaturants. After purification the final products of each of these expression systems required 6 M urea to maintain solubility. However, the rhZP proteins expressed by CHO cells were secreted into the media, and the soluble proteins could be purified to near homogeneity. In this report the expression and purification procedures used to produce and isolate these secreted proteins are described.