Seasoning of Aspen

Aspen is nor; the major forest type in the Lake States, and extensive stands are reaching maturity. Increasing quantities are being cut, and much is nor; being put to new and more exacting uses that require better air - seasoning and kiln-drying practices. The recent favorable market for green aspen lumber appears to be falling off, and the time may soon come when operators are no longer able to move green aspen. Such a change can be met by manufacturing better-quality aspen lumber and by carefully seasoning it to the desired moisture content to make it more acceptable. This report describes the principles of air seasoning and kiln drying as developed from research at the Forest Products Laboratory, with specific recommendations for the seasoning of aspen lumber, flitches, and shook stock. More detailed information may be obtained from the publications listed at the end of this report, most of which are available at the Forest Products Laboratory

Patterns of contribution to citizen science biodiversity projects increase understanding of volunteers’ recording behaviour

The often opportunistic nature of biological recording via citizen science leads to taxonomic, spatial and temporal biases which add uncertainty to biodiversity estimates. However, such biases may also give valuable insight into volunteers’ recording behaviour. Using Greater London as a case-study we examined the composition of three citizen science datasets – from Greenspace Information for Greater London CIC, iSpot and iRecord - with respect to recorder contribution and spatial and taxonomic biases, i.e. when, where and what volunteers record. We found most volunteers contributed few records and were active for just one day. Each dataset had its own taxonomic and spatial signature suggesting that volunteers’ personal recording preferences may attract them towards particular schemes. There were also patterns across datasets: species’ abundance and ease of identification were positively associated with number of records, as was plant height. We found clear hotspots of recording activity, the 10 most popular sites containing open water. We note that biases are accrued as part of the recording process (e.g. species’ detectability) as well as from volunteer preferences. An increased understanding of volunteer behaviour gained from analysing the composition of records could thus enhance the fit between volunteers’ interests and the needs of scientific projects

Spectroscopic requirements for HALOE: An analysis of the HCl and HF channels

Spectral line parameters that have absorption features within the HCl and HF channels of the Halogen Occultation Experiment (HALOE) were evaluated. Line positions and identification of stratospheric and solar absorption features in both channels are presented based on an analysis of high-resolution, balloon-borne solar occultation spectra. For the relevant HCl and HF lines and for transitions of the interfering species, the accuracy of the following spectral parameters was assessed: line positions, line strengths, lower state energies, air-broadened collisional half-widths, and temperature dependence of the air-broadened half-widths. In addition, since the HALOE instrument and calibration cells are filled with mixtures of HCl in N2 and HF in N2, the self-broadened and N2-broadened HF and HCl half-widths were also considered

Plant disease - black spot (anthracnose) of grapes

Black spot or Anthracnose of grapes caused by the fungus Elsinoe ampelina is a widespread and serious disease. In commercial vineyards it is often responsible for considerable reduction in yield and quality of fruit, and in home gardens also it may prove very damaging. Under commercial conditions the disease has proved difficult to control in seasons favourable for its development despite the routine application of accepted fungicides. Fortunately, preliminary results of recent spray trials indicate that greatly improved control is likely to result in future from the use of a number of new fungicides

A high-resolution gamma-ray and hard X-ray spectrometer for solar flare observations in Max 1991

A long duration balloon flight instrument for Max 1991 designed to study the acceleration of greater than 10 MeV ions and greater than 15 keV electrons in solar flares through high resolution spectroscopy of the gamma ray lines and hard X-ray and gamma ray continuum is described. The instrument, HIREGS, consists of an array of high-purity, n-type coaxial germanium detectors (HPGe) cooled to less than 90 K and surrounded by a bismuth germanate (BGO) anticoincidence shield. It will cover the energy range 15 keV to 20 MeV with keV spectral resolution, sufficient for accurate measurement of all parameters of the expected gamma ray lines with the exception of the neutron capture deuterium line. Electrical segmentation of the HPGe detector into a thin front segment and a thick rear segment, together with pulse-shape discrimination, provides optimal dynamic range and signal-to-background characteristics for flare measurements. Neutrons and gamma rays up to approximately 0.1 to 1 GeV can be detected and identified with the combination of the HPGe detectors and rear BGO shield. The HIREGS is planned for long duration balloon flights (LDBF) for solar flare studies during Max 1991. The two exploratory LDBFs carried out at mid-latitudes in 1987 to 1988 are described, and the LDBFs in Antarctica, which could in principle provide 24 hour/day solar coverage and very long flight durations (20 to 30 days) because of minimal ballast requirements are discussed

Plant diseases - Bacterial canker of tomatoes / Cover spray for the control of celery leaf spot / Stunt disease in subterranean clover

Bacterial canker is perhaps the most serious disease confronting tomato growers in Western Australia. Once established in a planting, it is very difficult to control and it can also persist in the soil or on the supporting stakes from season to season. The disease was first recorded in Western Australia in December, 1945, when it was introduced in seed of the Tatura variety ex the Eastern States. Since then it has become very widespread. INVESTIGATIONS commenced during the past autumn have indicated that Bordeaux 4:4:40 is the most effective of eight fungicidal preparations tested as cover sprays for the control of celery leaf spot. THE stunt virus disease of subterranean clover, formerly referred to as little leaf, was found during the winter of 1958 in the South Coastal agricultural areas at Esperance, Gibson and Gairdner River on subterranean clover varieties Bacchus Marsh, Dwalganup and Yarloop. Reports indicate that it also occurred in 1955 at Esperance

Plural-wavelength flame detector that discriminates between direct and reflected radiation

A flame detector employs a plurality of wavelength selective radiation detectors and a digital signal processor programmed to analyze each of the detector signals, and determine whether radiation is received directly from a small flame source that warrants generation of an alarm. The processor's algorithm employs a normalized cross-correlation analysis of the detector signals to discriminate between radiation received directly from a flame and radiation received from a reflection of a flame to insure that reflections will not trigger an alarm. In addition, the algorithm employs a Fast Fourier Transform (FFT) frequency spectrum analysis of one of the detector signals to discriminate between flames of different sizes. In a specific application, the detector incorporates two infrared (IR) detectors and one ultraviolet (UV) detector for discriminating between a directly sensed small hydrogen flame, and reflections from a large hydrogen flame. The signals generated by each of the detectors are sampled and digitized for analysis by the digital signal processor, preferably 250 times a second. A sliding time window of approximately 30 seconds of detector data is created using FIFO memories

Depressive Symptoms and 24-Hour Ambulatory Blood Pressure in Africans: The SABPA Study

Disturbances in circadian rhythm might play a central role in the neurobiology of depression. We examined the association between depressive symptoms and 24-hour ambulatory BP in a sample of 405 (197 black and 208 Caucasian) urbanized African teachers aged 25 to 60 yrs (mean 44.6 ± 9.6 yrs). Depressive symptoms were assessed using the self-administered 9-item Patient Health Questionnaire (PHQ-9). After adjusting for age, sex, and ethnicity, participants with severe depressive symptoms (PHQ-9 ≥ 15) had higher odds of hypertension defined from ambulatory BP and/or use of antihypertensive medication (odds ratio = 2.19, 95% CI, 1.00–4.90) in comparison to participants with no symptoms. Compared to Caucasians with no depressive symptoms, those with severe symptoms had blunted nocturnal systolic BP drop of 4.7 mmHg (95% CI, −0.5 to 10.0, P = 0.07). In summary, depressive symptoms were associated with the circadian BP profile in black and Caucasian Africans