Grown organic matter as a fuel raw material resource

An extensive search was made on biomass production from the standpoint of climatic zones, water, nutrients, costs and energy requirements for many species. No exotic species were uncovered that gave hope for a bonanza of biomass production under culture, location, and management markedly different from those of existing agricultural concepts. A simulation analysis of biomass production was carried out for six species using conventional production methods, including their production costs and energy requirements. These estimates were compared with data on food, fiber, and feed production. The alternative possibility of using residues from food, feed, or lumber was evaluated. It was concluded that great doubt must be cast on the feasibility of producing grown organic matter for fuel, in competition with food, feed, or fiber. The feasibility of collecting residues may be nearer, but the competition for the residues for return to the soil or cellulosic production is formidable

How the asymmetry of internal potential influences the shape of I-V characteristic of nanochannels

Ion transport in biological and synthetic nanochannels is characterized by such phenomena as ion current fluctuations, rectification, and pumping. Recently, it has been shown that the nanofabricated synthetic pores could be considered as analogous to biological channels with respect to their transport characteristics \cite{Apel, Siwy}. The ion current rectification is analyzed. Ion transport through cylindrical nanopores is described by the Smoluchowski equation. The model is considering the symmetric nanopore with asymmetric charge distribution. In this model, the current rectification in asymmetrically charged nanochannels shows a diode-like shape of $I-V$ characteristic. It is shown that this feature may be induced by the coupling between the degree of asymmetry and the depth of internal electric potential well. The role of concentration gradient is discussed

Trends in rotator cuff repair rates and comorbidity burden among commercially insured patients younger than the age of 65 years, United States 2007-2016

BACKGROUND: Prior US studies have shown increasing rotator cuff repair rates through 2009. We hypothesize that rotator cuff repair rates are continuing to increase and the comorbidity profiles of patients are becoming more complex over time. METHODS: We identified rotator cuff repairs in a large US cohort of people 18-64 years of age with ≥1 year of commercial insurance coverage. Repair rate trends across time were standardized by age, sex, and geographic region. Procedures were categorized as inpatient vs. outpatient and as arthroscopic vs. open. Prevalent comorbidities were defined as 1 inpatient diagnosis claim or 2 outpatient diagnosis claims during the year before rotator cuff repair. General population comorbidity prevalence was determined based on a random 5% sample of the commercially insured population and compared with patients with rotator cuff repair using standardized morbidity ratios. RESULTS: From 2007 to 2016, 314,239 rotator cuff repairs were identified (165 repairs per 100,000 person-years). Rotator cuff repairs were performed more frequently in men, older people, and in the Midwest. Across time, cuff repair rates increased by 1.6% per year (95% confidence interval [CI] = +1.4%-1.7%) adjusting for demographics. The highest increases in repair rates were observed among patients aged 50-64 years (+2.0%, 95% CI = +1.8%-2.2%). Rotator cuff repairs were more frequently performed using an arthroscopic approach and in an outpatient setting in later calendar years. In 2016, 83% of rotator cuff repairs were arthroscopic procedures and 99% were performed as outpatient procedures. Comorbidity prevalence in rotator cuff repair patients increased across calendar time by 4.5% per year for hypertension (95% CI = +4.2%-4.7%), 2.3% per year for diabetes (+1.9%-2.7%), 0.9% per year for hypercholesterolemia (+0.3%-1.5%), 2.9% for congestive heart failure (+0.8%-4.9%), 4.2% for peripheral vascular disease (+2.4%-6.0%), and 4.2% for chronic pulmonary disease (+3.6%-4.8%). Comorbidity prevalence in repair patients was higher than prevalence in the general population, and prevalence relative to the general population was most heightened during later calendar years. For example, hypertension prevalence was 1.58 times higher in repair patients than the general population in 2007 (95% CI = 1.53-1.62), and 2.06 times higher in 2016 (95% CI = 2.02-2.11). CONCLUSION: Rotator cuff repair is becoming more frequent in the US commercially insured population, particularly in those 50-64 years of age. More rotator cuff repairs are being performed using an arthroscopic approach and in an outpatient setting. Over time, the comorbidity profile of patients undergoing rotator cuff repair is becoming more complex with greater prevalence of numerous conditions, including hypertension, peripheral vascular disease, and chronic pulmonary disease

On the Accuracy of A.C. Flux Leakage, Eddy Current, EMAT and Ultrasonic Methods of Measuring Surface Connecting Flaws in Seamless Steel Tubing

The objective of this study was to perform a comparative experimental evaluation to determine the detection sensitivity, classification (fJaw type) and depth sizing accuracy of A.C. flux leakage, single-frequency eddy current, electromagnetic acoustic transducer (EMAT) generated surface waves, and broadband ultrasonic methods for the measurement of complex surface connecting flaws in hot rolled, seamless, ferritic tubing. Since it was of interest to invest NDE techniques over a wide range of capabilities, tubing having flaw depths far exceeding industry standards was tested and evaluated. Results of the study will be used to provide a benchmark assessment of these NDE methods, from which decisions concerning production test systems can be made

Use of soil moisture information in yield models

There are no author-identified significant results in this report

Generation of finite wave trains in excitable media

Spatiotemporal control of excitable media is of paramount importance in the development of new applications, ranging from biology to physics. To this end we identify and describe a qualitative property of excitable media that enables us to generate a sequence of traveling pulses of any desired length, using a one-time initial stimulus. The wave trains are produced by a transient pacemaker generated by a one-time suitably tailored spatially localized finite amplitude stimulus, and belong to a family of fast pulse trains. A second family, of slow pulse trains, is also present. The latter are created through a clumping instability of a traveling wave state (in an excitable regime) and are inaccessible to single localized stimuli of the type we use. The results indicate that the presence of a large multiplicity of stable, accessible, multi-pulse states is a general property of simple models of excitable media.Comment: 6 pages, 6 figure