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G McLaren

Publications and source records attributed to G McLaren.

6 recordsLinked to original sources
PubMed2003

Identification of QTL for growth- and grain yield-related traits in rice across nine locations of Asia.

Rice double-haploid (DH) lines of an indica and japonica cross were grown at nine different locations across four countries in Asia. Genotype-by-environment (G x E) interaction analysis for 11 growth- and grain yield-related traits in nine locations was estimated by AMMI analysis. Maximum G x E interaction was exhibited for fertility percentage number of spikelets and grain yield. Plant height was least affected by environment, and the AMMI model explained a total of 76.2% of the interaction effect. Mean environment was computed by averaging the nine environments and subsequently analyzed with other environments to map quantitative trait loci (QTL). QTL controlling the 11 traits were detected by interval analysis using mapmaker/qtl. A threshold LOD of >/=3.20 was used to identify significant QTL. A total of 126 QTL were identified for the 11 traits across nine locations. Thirty-four QTL common in more than one environment were identified on ten chromosomes. A maximum of 44 QTL were detected for panicle length, and the maximum number of common QTL were detected for days to heading detected. A single locus for plant height (RZ730-RG810) had QTL common in all ten environments, confirming AMMI results that QTL for plant height were affected the least by environment, indicating the stability of the trait. Two QTL were detected for grain yield and 19 for thousand-grain weight in all DH lines. The number of QTL per trait per location ranged from zero to four. Clustering of the QTL for different traits at the same marker intervals was observed for plant height, panicle number, panicle length and spikelet number suggesting that pleiotropism and or tight linkage of different traits could be the possible reason for the congruence of several QTL. The many QTL detected by the same marker interval across environments indicate that QTL for most traits are stable and not essentially affected by environmental factors.

Asia↗
PubMed2001

Bioinformatics for rice resources.

The distinguishing feature of the 'new biology' is that it is information intensive. Not only does it demand access to and assimilation of vast data sets accumulated by engineered laboratory processes, but it also demands a previously unimaginable level of data integration across data types and sources. There are various information resources available for rice. In addition, there are various information resources that are not focused on rice but that contain rice data. The challenge for rice researchers and breeders is to access this wealth of data meaningfully. This challenge will grow significantly as international efforts aimed at sequencing the entire rice genome come into full swing. Only through concerted efforts in bioinformatics will the power of these public data be brought to bear on the needs of rice researchers and breeders worldwide. These efforts will need to focus on two large but distinct areas: (1) development of an effective bioinformatics infrastructure (hardware systems, software systems, and software engineers and support staff) and (2) computational biology research in visualization and analysis of very large, complex data sets, such as those that will be developed using high-throughput expression technologies, large-scale insertional mutagenesis, and biochemical profiling of various types. In the midst of the large flow of high-throughput data that the international rice genome sequencing efforts will produce, it is also imperative that integration of those data with unique germplasm data held in trust by the CGIAR be a part of the informatics infrastructure. This paper will focus on the state of rice information resources, the needs of the rice community, and some proposed bioinformatics activities to support these needs.

Algorithms↗
PubMed2001

Comparison of sampling methods for obtaining accurate coagulation values in hemodialysis patients with heparinized central venous catheters.

Monitoring coagulation values in hemodialysis (HD) is integral to the care of patients with central venous catheters (CVCs) to maintain catheter patency. HD patients can have problems providing blood samples and may experience discomfort with venipuncture, but no consensus in the literature is available to identify a reliable and efficient method of obtaining an international normalization ratio (INR) value from a heparinized CVC line. This was a comparative study of three different methods of blood sampling for INR values. The INR samples were obtained from a peripheral venipuncture site, the CVC line, and the arterial bloodline sample port. The peripheral INR sample was used as the gold standard. The study occurred in a 60-station hemodialysis center in a 428-bed, urban, acute care hospital. The sample included 33 HD patients with patent dialysis CVC lines. Blood samples were drawn with a standardized protocol during one HD session from each of the three sites. The Pearson correlation coefficient for the peripheral sample versus the CVC line sample was 0.97 (p < 0.001) and was 0.99 (p < 0.001) between the peripheral sample and the arterial bloodline sample. Results revealed that both alternative methods are suitable for taking INR samples. As a result of this study, the arterial bloodline sample port method for INR sampling was introduced into the HD unit at this hospital. This method has proven to be simple, quick, accurate, and noninvasive to renal patients.

Adolescent↗
PubMed1989

Maximum expiratory airflow during chest physiotherapy on ventilated patients before and after the application of an abdominal binder.

Chest physiotherapy using a manual ventilation technique was carried out on 9 intubated patients. One patient was studied on two occasions. The maximum expiratory flow rate (MEFR) was recorded during: (A) manual ventilation without physiotherapy, (B) manual ventilation with chest compression, (C) manual ventilation and chest compression, after application of the abdominal binder. Statistical analysis was carried out to allow for differences in tidal volume (Vt). Chest physiotherapy increased the mean MEFR and application of an abdominal binder (together with physiotherapy) caused a further increase in MEFR. The mean MEFR (assuming a common Vt of 1360 ml) in each group was; (A) = 73.3 l min-1, (B) = 103.9 l min-1, (C) = 113.93 l min-1.

Abdomen↗