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There is concern that changes to the operating speed and size of spindles on cotton picker harvesters over the years have resulted in a general decrease in cotton fiber quality, especially spindle twists, preparation, and neps. Previous research showed that spindle speeds of 3000 and 4000 rpm had more detrimental effects on picker stalk loss, trash levels in seed cotton, and cotton fiber quality than a spindle speed of 2000 rpm. This study was conducted to check fiber quality effects between 2000 and 2800 rpm in order to further define the optimum spindle speed range. Field tests were conducted for the 2008 and 2009 crop years by the USDA, Agricultural Research Service, Southwestern Cotton Ginning Research Laboratory in Mesilla Park, New Mexico. Three cotton varieties were grown under furrow-irrigated conditions in southern New Mexico and harvested with a modified one-row cotton picker each year using a ground speed of 0.85 m s-1 (1.9 miles h-1) and spindle speeds of 2000, 2200, 2500, and 2800 rpm. The tests were replicated four times. No significant differences in stalk losses in the field were found. Significantly more trash was present in seed cotton picked with spindle speeds of 2200, 2500, and 2800 rpm than in seed cotton picked with a spindle speed of 2000 rpm. Differences in trash content were eliminated by seed cotton cleaning (same for all treatments). HVI classing data showed no significant differences among spindle speed treatments. Differences due to spindle speed for AFIS nep count, short fiber count, trash count, dust count, and seed coat nep count were non-significant at each of the four locations tested in the yarn preparation process. Results from open-end spinning tests, including opening and cleaning waste, total card waste, ends down, yarn strength, yarn elongation, neps, thick places, and thin places showed no significant differences due to spindle speed. Based on these results, the 2000 rpm spindle speed is optimal because trash in the seed cotton is reduced which reduces ginning costs; however; only minimal differences are present at spindle speeds up to 2800 rpm.

Because of the Federal Clean Air Act Amendments of 1990, the San Joaquin Valley Unified Air Pollution Control District (SJVUAPCD) began defining Best Available Control Technology (BACT) for NOx emissions from cotton gin drying system gas-fired burners in its jurisdiction. The NOx emission levels of conventionally used, direct-fired burners were unknown, as was how direct-fired burners would compare against newer lo-NOx burners or against the proposed SJVUAPCD NOx emission standard of 60 ppm or less. Replicated laboratory studies were designed to determine the emissions and fuel efficiency of both direct-fired and lo-NOx burner designs. NOx emission levels during the test averaged from 3 ppm for one of the lo-NOx designs to 36 ppm for a direct-fired burner when tested over four firing rates. An economic analysis of the specific cost of NOx reduction achieved by substituting a lo-NOx burner for a direct-fired burner showed an annual capitalized cost of $13,945/tonne ($12,648/T) of NOx reduction. The SJVUAPCD has an upper limit of $10,670/tonne ($9700/T) of NOx reduction to qualify for definition as BACT. Using this economic criterion, lo-NOx burners do not meet the definition of BACT for cotton gins for the SJVUAPCD, and, based upon conferring with industry and environmental specialists, would not for the rest of the United States.

Three cotton varieties were grown under furrow-irrigated conditions in southern New Mexico and hand-harvested so that individual bolls remained intact. The cotton bolls were conditioned in a controlled atmosphere and then subjected to a single cotton picker spindle operating at a speed of 1000 to 3000 rpm. Two spindle designs were studied: a 12.7-mm (-in.) round, tapered, barbed spindle and a 4.8-mm (3/16-in.) square spindle that was straight and smooth. Mass measurements were taken to determine the portion of seed cotton not picked and the portion that would be ejected from the spindle (fly-off). A force gauge was used to determine the peak force that was needed to pull the seed cotton from the spindle. Moisture content of the bolls used in the test ranged from 9% to 10% d.b. Results showed that the smaller, straight spindle was more aggressive in removing cotton from the boll. There was approximately twice as much fly-off from the barbed spindle than from the smaller straight spindle at any given speed. Fly-off also increased exponentially for each spindle type as the speed was increased. The peak force required to remove the seed cotton from the spindle ranged from 50% to 100% more for the smaller straight spindle than from the barbed spindle. For both spindles, the peak force requirement was approximately doubled each time the speed was increased by 1000 rpm, indicating an exponential relationship between speed and wrap tightness. Additionally, field tests were conducted for the 2005 and 2006 crop years by the USDA, Agricultural Research Service, Southwestern Cotton Ginning Research Laboratory in Mesilla Park, New Mexico.

Seven commercially available portable cotton bale moisture content (mc) meter-probe combinations were purchased by each of the three Agricultural Research Service Cotton Ginning Research Units and examined for precision and accuracy when used with commercially ginned cotton. The devices were used to measure the mc at the same six locations on a total of 96 cotton bales. Lint samples were obtained from the same locations in the bales for mc determination by the oven method resulting in more than 7000 meter readings with corresponding reference mc values. Based on oven-mc, the lint samples had mc in the range 2.3% to 9.4% wet basis. The oven-mc wet basis for the different samples in the same bale had a standard error from 0.15% to 0.42% wet basis. The different meters produced significantly different readings from each other, and these were significantly different from the oven-based mc. Most of the meters were found to have a significant offset from the oven-based mc ranging from -3.3 to 3.3 percentage points. However, the standard deviation of the difference between the individual readings of the meters and the oven-based mc resulted in estimates of precision of plus or minus one percentage point for most of the individual meters.

The study of the addition of water to cotton at ginning dates back to the early 1950s. Since that time, technologies have changed, allowing for more control and higher volumes of water to be added to cotton at the lint slide than ever before. The objective of this study was to determine an acceptable bale moisture range within which fiber quality, yarn quality, and dyed fabric quality degradation can safely be avoided after six months of bale storage. Approximately 22.7 kg (50 lbs) of cotton were sampled from each of the three bales for each of the four moisture treatments after six months in storage. In addition to the HVI fiber properties, additional testing of the fibers was performed on the Advanced Fiber Information System (AFIS), as well as a microbial assay to determine any microbial damage to the cotton during storage. The resulting 20/1 open-end spun yarns were subjected to typical yarn quality measurements (C.V., defects, strength, and elongation) and then circular-knit into panels so that yarn from each treatment was butt-knit to more easily observe color or shade change. HVI data indicated that the moisture treatment levels and storage period had an adverse impact on color Rd and +b with increasing amounts of water added at the lint slide. Although microbial data were collected, the data did not indicate any significant activity during the six months of storage. As for yarn quality, it appears that 9.1 kg (20 lbs) or more of water added to bales of cotton at the lint slide resulted in significant as well as practical reductions in yarn quality. With respect to the six-month storage period and the treatments used in this study, although there were color changes to the cotton fiber, there appeared to be no impact on the bleached and dyed fabric. Additionally, it appears that the point of diminishing return for adding moisture to cotton at the lint slide lies between 6% and 8.5%.

The presence of unpaired copies of a gene during meiosis triggers silencing of all copies of the gene in the diploid ascus cell of Neurospora. This phenomenon is called meiotic silencing and on the basis of genetic studies appears to be a post-transcriptional gene silencing (PTGS) mechanism. Previously, meiotic silencing was defined to be induced by the presence of a DNA region lacking an identical segment in the homologous chromosome. However, the determinants of unpaired DNA remained a mystery. Using the Ascospore maturation-1 (Asm-1) gene, we defined what needs to be “unpaired” to silence a gene. For efficient silencing, an unpaired region of DNA needs to be of a sufficient size and contain homology to the reporter transcript. The greater the size of the loop and the larger the homology to the reporter transcript, the better the resulting meiotic silencing is. Conversely, regions not containing homology to the transcript, e.g., intergenic regions, did not silence the reporter. Surprisingly, unpaired fragments lacking a canonical promoter silenced the reporter. Additionally, we detected the unpairing-dependent loss of a transcript during meiotic silencing. Our observations further support a PTGS mechanism for meiotic silencing and offer insight into the evolutionary consequences resulting from this novel meiotic checkpoint.

Laboratory experiments on cyclone designs and operating parameters using EPA Reference Method 201A is labor intensive. The intent of this experiment was to evaluate an electronic particulate monitor as an alternative dust cyclone performance measurement instrument. The particulate monitor was installed in line with fiberglass filters that captured dust escaping from test cyclones. Mass on the filters was compared to particulate monitor output. Three cyclones, four loading rates and four replicates were run in random order. A linear correlation of about 85% was observed when data was separated by cyclone size. Cost and time savings are promising, but dust loading across a range of various particle size distributions still needs to be evaluated.

Seed cotton samples were dried using a radio frequency dryer. Changes in moisture content, fiber quality, and seed quality were measured. Results are pending as of this submission.

Three cotton varieties were grown under furrow-irrigated conditions in southern New Mexico and harvested at three different spindle speeds (1500, 2000, and 2400 rpm). Results for stalk losses, trash content, and fiber quality are presented.

During vertebrate mesoderm formation, fates are established according to position in the dorsoventral (D/V) axis of the embryo. Initially, maternal signaling divides nascent mesoderm into axial (dorsal) and non-axial (ventral) domains. Although the subsequent subdivision of non-axial mesoderm into multiple D/V fate domains is known to involve zygotic Wnt8 and BMP signaling as well as the Vent/Vox/Ved family of transcriptional repressors, how levels of signaling activity are translated into differential regulation of fates is not well understood. To address this question, we have analyzed zebrafish embryos lacking Wnt8 and BMP2b. Zebrafish wnt8; swr (bmp2b) double mutants display a progressive loss of non-axial mesoderm and a concomitant expansion of axial mesoderm during gastrulation. Mesoderm induction and specification of the axial domain occur normally in wnt8; swr mutants, but dorsal mesoderm genes eventually come to be expressed throughout the mesoderm, suggesting that the establishment of non-axial mesoderm identity requires continual repression of dorsal mesoderm factors, including repressors of ventral genes. Loss-of-function for Vent, Vox, and Ved phenocopies the wnt8; swr mutant phenotype, consistent with Wnt8 and BMP2b maintaining non-axial mesoderm identity during gastrulation through the regulation of these three transcriptional repressors. We postulate that timely differentiation of the mesoderm requires the maintenance of non-axial mesoderm identity by Wnt8 and BMP2b at the onset of gastrulation followed by subdivision of the non-axial mesoderm into different functional domains during gastrulation.

Three cotton varieties were grown under furrow-irrigated conditions in southern New Mexico and harvested with three different spindle picker machine/speed combinations. Results for harvest losses and trash content showed a highly significant interaction between variety and machine/speed combination. This interaction caused difficulty in interpreting results from this 1-year study. Therefore, a follow-up study is planned.

Three cyclone separators were tested in a laboratory setting at four trash loading rates. Cyclone collection efficiency for over-sized cyclones was slightly less than the efficiency of a standard-sized cyclone, averaging 98.42% and 98.64%, respectively. Cyclone collection efficiency increased as trash loading rate increased, with average values ranging from 97.94% at a trash-loading rate of 2 g/m3(0.88 grain/ft3) to an average of 98.96% at a trash-loading rate of 16 g/m3(7.0 grain/ft3). Cyclone static pressure drops for over-sized cyclones were much less than those for standard-sized cyclones, with the static pressure drop in an over-sized cyclone averaging 28% of the value for a standard-sized cyclone. The authors concluded that, with their lower pressure drop, over-sized cyclones are more compatible than standard-sized cyclones for replacing lint baskets on low pressure airflow systems that use axial-flow fans.

Three cotton varieties were grown under furrow-irrigated conditions in southern New Mexico and harvested with three different spindle picker machine/speed combinations. Results for harvest losses and trash content showed a highly significant interaction between variety and machine/speed combination. This interaction caused difficulty in interpreting results from this 1-year study. Therefore, a follow-up study is planned.

Simultaneous source testing and boundary line testing were conducted at an operating cotton gin in the San Joaquin Valley, California. Results of the simultaneous testing were compared regarding their indication of compliance with air pollution regulations and standards.