A Study of Catalytic Reactions on Semiconductors: Hydrogen Deuterium Exchange and Formic Acid Decomposition on Chemically-Doped Germanium

Summary: Rates and activation energies for the hydrogen-deuterium exchange and formic acid vapor decomposition were measured on a series of chemically-doped germanium catalyst over the temperature range 100° to 400°. The germanium catalyst were intrinsic, and n or p-type extrinsic semiconductors; the position of the Fermi level of the solid was located suitably on the forbidden energy gap. Kinetic parameters of the exchange and decomposition reactions were related to the Fermi level (electronic chemical potential) of the solid. Their dependence suggested that the rate-limiting processes involved electronic charge shifts between adsorbate and semiconductor. Two different rate processes appeared to limit the hydrogen-deuterium exchange. A process involving an electron shift from adsorbate to solid appeared to control the rate in the region of n-type semiconductivity. In the region of p-type semiconductivity, the rate-determining process appeared to be an electron shift in the opposite direction (from solid to absorbate). Dehydrogenation and dehydration of formic acid on germanium were observed. Dehydrogenation was the predominant method of decomposition on p-type germanium; however, dehydrogenation on n-type germanium could not be detected. A process involving an electron shift from adsorbate to solid appeared to control the dehydrogenation reaction. Dehydration of formic acid occurred on all germanium catalyst, and appeared independent of the Fermi level of the solid. Both dehydrogenation and dehydration of formic acid appeared to be primary decomposition processes at the lower temperatures. There was evidence, however, that the water gas equilibrium affected the distribution of products at some of the higher temperatures that were used. Nonstoichimetry of dehydrogenation products in the gas phase over p-type germanium was detected, and seemed to be best explained by the removal of hydrogen atoms by the germanium during the process of formic acid decomposition

La Certitude

(1) Je suis en ce moment, comme tout le monde peut le voir, dans une salle et non pas dehors. Je suis debout et non assis ou couché. Je porte des vêtements et ne suis pas tout nu. Je parle à voix haute et ne suis pas en train de chanter ou de chuchoter ou de me taire. J'ai dans la main quelques feuilles de papier sur lesquelles quelque chose est écrit. Il y a beaucoup d'autres personnes dans la salle où je me trouve. Il y a des fenêtres d'un côté et une porte de l'autre. (2) Eh bien, ces dive..

“Somebody to Say ‘Come On We Can Sort This’”:A Qualitative Study of Primary Care Consultation Among Older Adults With Symptomatic Foot Osteoarthritis

OBJECTIVE: To examine the experiences of primary care consultation among older adults with symptomatic foot osteoarthritis (OA). METHODS: Eleven participants (6 women and 5 men) ages 56–80 years who had radiographically confirmed symptomatic foot OA and consulted a general practitioner in the last 12 months for foot pain were purposively sampled. Semistructured interviews explored the nature of the foot problem, help-seeking behaviors, and consultation experiences. Verbatim transcripts were analyzed using interpretative phenomenological analysis. RESULTS: The decision to consult a physician was often the outcome of a complex process influenced by quantitative and qualitative changes in symptoms, difficulty maintaining day-to-day roles and responsibilities and the effect this had on family and work colleagues, and a reluctance to present a fragile or aging self to the outside world. Self-management was commonly negotiated alongside multimorbidities. Upon seeking help, participants often believed they received limited information, they were given a brief or even cursory assessment, and that treatment was focused on the prescription of analgesic drugs. CONCLUSION: This is the first qualitative study of primary care experiences among patients with symptomatic foot OA. The experience of primary care seldom appeared to move beyond a label of arthritis and an unwelcome emphasis on pharmacologic treatment

Clinical diagnosis of symptomatic midfoot osteoarthritis:cross-sectional findings from the Clinical Assessment Study of the Foot

OBJECTIVE: To derive a multivariable diagnostic model for symptomatic midfoot osteoarthritis (OA). METHODS: Information on potential risk factors and clinical manifestations of symptomatic midfoot OA was collected using a health survey and standardised clinical examination of a population-based sample of 274 adults aged ≥50 years with midfoot pain. Following univariable analysis, random intercept multi-level logistic regression modelling that accounted for clustered data was used to identify the presence of midfoot OA independently scored on plain radiographs (dorso-plantar and lateral views), and defined as a score of ≥2 for osteophytes or joint space narrowing in at least one of four joints (first and second cuneometatarsal, navicular-first cuneiform and talonavicular joints). Model performance was summarised using the calibration slope and area under the curve (AUC). Internal validation and sensitivity analyses explored model over-fitting and certain assumptions. RESULTS: Compared to persons with midfoot pain only, symptomatic midfoot OA was associated with measures of static foot posture and range-of-motion at subtalar and ankle joints. Arch Index was the only retained clinical variable in a model containing age, gender and body mass index (BMI). The final model was poorly calibrated (calibration slope, 0.64, 95% CI: 0.39, 0.89) and discrimination was fair-to-poor (AUC, 0.64, 0.58, 0.70). Final model sensitivity and specificity were 29.9% (22.7, 38.0) and 87.5% (82.9, 91.3), respectively. Bootstrapping revealed the model to be over-optimistic and performance was not improved using continuous predictors. CONCLUSIONS: Brief clinical assessments provided only marginal information for identifying the presence of radiographic midfoot OA among community-dwelling persons with midfoot pain

The Effect of Two Planting Dates and Methods on Snap Bean (Phaseolus Vulgaris) Production in a Tunnel House

The study was conducted to evaluate the impact of two planting dates and methods on snap bean yields in a tunnel house. The main plots included planting dates March 17 and 31, 2016 for first and second plantings. The sub-plots consisted of planting Method 1 where one seed per hill was planted every 4” apart, and planting Method 2 where three seeds per hill were planted every 12” apart; each treatment combination was replicated four times. The results of the study showed that it took 55 days for the snap beans to be ready for harvest for both planting dates. Also, there were no significant differences in yields between planting dates, and there were no significant differences in yields between planting methods. This notwithstanding, it may appear that Method 2 would better for weed control because the plants will be well spaced compared to Method 1. Keywords: Tunnel House, Snap bean Planting Dates, Snap bean Planting Methods, Snap bean Yield

The Evaluation of Two Different Harvesting \u27Topbunch\u27 and \u27Hi-Crop\u27 Collards (Brassica Oleracea (L)) Leaves from Plants Grown in a Wiregrass Tunnel House

A study was conducted to determine if a 100% or 50% harvest intensity of ‘Topbunch’ collards leaves could be a recommended practice for Tunnel House producers. The experiment was conducted as a split-plot design with harvest dates as main plots, and harvesting intensity of 100% or 50% of leaves as sub-plots. All treatments were replicated three times, drip irrigated, and fertilized according to soil test recommendations. The results showed significant interactions between harvest methods and dates for number and weight of leaves harvested. There were also significant differences for the weight of leaves harvested and numbers. The leaf recovery rates were greater for plants that had 50% of their leaves harvested compared to those which had 100% of their leaves harvested. This higher recovery rate for the former suggests that the harvest interval could be reduced in the future from 21 to 15 or 18 days

Air and Soil Temperature Readings, Growing Degree Days, and Chilling Hours Recorded in Two Wiregrass Tunnel Houses Located in East Central Alabama

The study examined air and soil temperature readings, growing degree days, and chilling hours recorded in two Wiregrass tunnel houses during the 2018-2019 season. The monthly average ambient temperature, was 15OF warmer inside the Tunnel House (75/60OF) during the Cool/Cold months, and 17OF warmer inside (90/73OF) during the Warm/Hot seasons of 2018 and 2019. Growing Degree Days heat unit (HU) accumulations were higher inside than outside 4,154 vs. 3,153 HU for the Cool/Cold months and 5,134 vs. 4,800 HU for the Warm/Hot months. Chilling hour accumulations were lower inside the tunnel houses than outside the tunnel houses, 601vs. 671 hr. Utilizing the temperature data from this study, a planting guide consisting of a Cool/Cold (September-February) season and Warm/Hot (March-August) season was developed for a list of crops which producers could plant. The results of this study provides information for growers to better plan their crop choices and planting schedules

The Effect of Two Different Harvesting Methods on the Yield of \u27Topbunch\u27 and \u27Hi-Crop\u27 Collards (Brassica Oleracea (L)) When Grown in a Wiregrass Tunnel House

A study was conducted to determine if 100% or 50% harvesting of collard leaves was a suitable recommendation for Tunnel House producers. The experiment was conducted as a split-split plot design with varieties as the main plots, harvesting 100% or 50% of leaves as the sub-plots, and days after transplanting as the subplots. All treatments were replicated three times, drip irrigated, and fertilized according to soil test recommendations. The results showed significant interactions between varieties and method of harvest, for leaf numbers and weight. Conversely, the varieties showed significant differences for yield but not leaf numbers. Both varieties showed significant increases in leaf numbers and yield at each harvest period when 50% of the leaves were harvested, instead of 100%. This approach led to higher leaf recovery rates suggesting that a 50% leaf harvest would result in higher yields, and reduce the harvest intervals from the present 21 to 12 or 18 days