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51.
Prevalence of type 2 diabetes increased from 2.5% of the US population in 1990 to 10.5% in 2018. This creates a major public health problem, due to increases in long-term complications of diabetes, including neuropathy, retinopathy, nephropathy, skin ulcers, amputations, and atherosclerotic cardiovascular disease. In this review, we evaluated the scientific basis that supports the use of physiologic insulin resensitization. Insulin resistance is the primary cause of type 2 diabetes. Insulin resistance leads to increasing insulin secretion, leading to beta-cell exhaustion or burnout. This triggers a cascade leading to islet cell destruction and the long-term complications of type 2 diabetes. Concurrent with insulin resistance, the regular bursts of insulin from the pancreas become irregular. This has been treated by the precise administration of insulin more physiologically. There is consistent evidence that this treatment modality can reverse the diabetes-associated complications of neuropathy, diabetic ulcers, nephropathy, and retinopathy, and that it lowers HbA1c. In conclusion, physiologic insulin resensitization has a persuasive scientific basis, significant treatment potential, and likely cost benefits.  相似文献   
52.
This paper presents a unique technique to control a photovoltaic (PV)-powered piston-type water pump. the method uses a linear motor mounted directly onto the piston rod of the pump. This linear motor method replaces the traditional piston-type water pump, which employs a DC motor with a bulky gear mechanism to convert the rotational motion of the motor to linear motion for the piston. The electric circuit used to control the linear motor employs a four-quadrant chopper, which uses four fast MOSFETs and a simple logic circuit for the switching. The experimental results show that the PV-powered linear motor system can be used as an alternative to the PV-powered DC motor gear system.  相似文献   
53.
The 2015 to 2020 Dietary Guidelines for Americans (DGAs) recognize the role of 100% fruit juice in health and in helping people meet daily fruit recommendations and state that 100% fruit juice is a nutrient‐dense beverage that should be a primary choice, along with water and low‐fat/fat‐free milk. The DGAs note that children are consuming 100% fruit juice within recommendations (that is, 120 to 180 mL/d for children aged 1 to 6 y and 236 to 355 mL/d for children aged 7 to 18 y). Evidence shows that compared to nonconsumers, those who consume 100% fruit juice come closer to meeting daily fruit needs and have better diet quality. In children, 100% fruit juice is associated with increased intakes of nutrients such as vitamin C, folate, and potassium. When consumed within the DGA recommendations, 100% fruit juice is not associated with overweight/obesity or childhood dental caries and does not compromise fiber intake. Preliminary data suggest that polyphenols in some 100% fruit juices may inhibit absorption of naturally occurring sugars. Given its role in promoting health and in helping people meet fruit needs, experts participating in a roundtable discussion agreed that there is no science‐based reason to restrict access to 100% fruit juice in public health nutrition policy and programs such as the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). Reducing or eliminating 100% fruit juice could lead to unintended consequences such as reduced daily fruit intake and increased consumption of less nutritious beverages (for example, sugar‐sweetened beverages).  相似文献   
54.
This study describes the identification of an aggregation pheromone for the pepper weevil,Anthonomus eugenii and field trials of a synthetic pheromone blend. Volatile collections and gas chromatography revealed the presence of six male-specific compounds. These compounds were identified using chromatographic and spectral techniques as: (Z)-2-(3,3-dimethylcyclohexylidene)ethanol, (E)-2-(3,3-dimethylcyclohexylidene)ethanol, (Z)-(3,3-dimethylcyclohexylidene)acetaldehyde, (E)-(3,3-dimethylcyclohexylidene)acetaldehyde, (E)-3,7-dimethyl-2,6-octadienoic acid (geranic acid), and (E)-3,7-dimethyl-2,6-octadien-1-ol (geraniol). The emission rates of these compounds from feeding males were determined to be about: 7.2, 4.8, 0.45, 0.30, 2.0, and 0.30µg/male/day, respectively. Sticky traps baited with a synthetic blend of these compounds captured more pepper weevils (both sexes) than did unbaited control traps or pheromone-baited boll weevil traps. Commercial and laboratory formulations of the synthetic pheromone were both attractive. However, the commercial formulation did not release geranic acid properly, and geranic acid is necessary for full activity. The pheromones of the pepper weevil and the boll weevil are compared. Improvements for increasing trap efficiency and possible uses for the pepper weevil pheromone are discussed. A convenient method for purifying geranic acid is also described.The mention of firm names or trade products does not imply endorsement or recommendation by the U.S. Department of Agriculture over other firms or similar products not mentioned. All programs and services of the U.S. Department of Agriculture are offered on a nondiscriminatory basis without regard to race, color, national origin, religion, sex, age, marital status or handicap.  相似文献   
55.
Two binding modes of the isobutyl-NH-Eps-Leu-Pro inhibitor tocathepsin B have been proposed. Molecular docking using an empiricalforce field was carried out to distinguish between the two modes.The search began with manual docking, followed by random perturbationsof the docking conformation and cycles of Monte Carlo minimization.Finally, molecular dynamics was carried out for the most favorabledocking conformations. The present calculations predict thatthe isobutyl-NH-Eps-Leu-Pro inhibitor preferentially binds tothe S' rather than the S subsites of cathepsin B. The S' bindingmode prediction is supported by the X-ray crystal structureof cathepsin B bound to a closely related ethyl-O-Eps-Ile-Proinhibitor, which was found to bind in the S' subsite with theC-terminal epoxy ring carbon making a covalent bond to the sulfuratom of Cys29. This agreement, in turn, validates our dockingstrategy. Furthermore, the calculations provide evidence thatthe dominant contribution to the total stabilization energyof the enzyme–inhibitor complex stems from the strongelectrostatic interaction between the negatively charged C-terminalcarboxylate group of the ligand and the positively charged imidazoliumrings of His110 and His111. The latter are stabilized and heldin an optimal orientation for interactions with the C-terminalend of the ligand through a salt bridge between the side chainsof His110 and Asp22. By comparison with the crystal structure,some insight into the specificity of the epoxyldipeptide familytowards cathepsin B inhibition has been extracted. Both thecharacteristics of the enzyme (e.g. subsite size and hydrophobicity)as well as the nature of the inhibitor influence the selectivityof an inhibitor towards an enzyme.  相似文献   
56.
There is a need for a better approach to measure construction productivity rigorously, multilaterally, longitudinally and decomposed into its components. In response, this paper offers a robust approach to analysing construction productivity at the firm level that has been lacking in the industry to date, by measuring the Total Factor Productivity (TFP) of 37 public-listed Malaysian construction firms over 14 years (2003–2016), based on the Färe-Primont index. In comparing different groups of building, civil and specialist construction firms, this is the first application of a meta-frontier framework to capture the technological gaps involved. Based on the construction firms’ financial data, it is found that TFP improvement generally occurs due to Technical Efficiency (TE) and Scale-Mix Efficiency (SME) (largely scope economies), and significant technological gaps exist among different groups. Moreover, the industry suffered a decline in technologically related production environment over the period – prompting the conclusion that long-term policy engagement should focus on technological improvements. The paper provides a robust approach to analysing construction productivity at the firm level that also can be used for accessing productivity components and technological gaps in construction and other industries.  相似文献   
57.
Older occupants in motor-vehicle crashes are more likely to experience injury than younger occupants. One possible reason for this is that increasing age is associated with increased prevalence of osteoporosis, which decreases bone strength.Crash-injury data were used with Bayes’ Theorem to estimate the conditional probability of AIS 3+ skeletal injury given that an occupant is osteoporotic for the injury to the head, spine, thorax, lower extremities, and upper extremities. This requires the conditional probabilities of osteoporosis given AIS 3+ injury for each of the body regions, which were determined from analysis of the Crash Injury Research and Engineering Network database. It also requires information on probability of osteoporosis in the crash-involved population and the probabilities of AIS 3+ skeletal injury to different body regions in crashes. The latter probabilities were obtained from the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) database. The former was obtained by modeling the probability of osteoporosis in the US populations using data from the 2006 National Health Examination Nutrition Survey and applying this model to the estimate of the crash-involved population in NASS-CDS. To attempt to account for the effects of age on injury outcome that are independent of osteoporosis, only data from occupants who were 60 years of age or older were used in all analyses.Results indicate that the only body region that experiences a statistically significant change in fracture injury risk with osteoporosis is the spine, for which osteoporosis increases the risk of AIS 3+ fracture by 3.28 times, or from 0.41% to 1.34% (p < 0.0001). This finding suggests that the increase in AIS 3+ injury risk with age for non-spine injuries is likely influenced by factors other than osteoporosis.  相似文献   
58.
Working memory deficits have been identified in bipolar disorder, but there is evidence suggesting that these deficits may be markers for psychosis rather than affective disorder. The current study examined this issue by comparing two groups of individuals with bipolar disorder, one with psychotic features and one without psychotic features, with a group of normal controls. Working memory was conceptualized as a multicomponent system that includes auditory and visuospatial short-term stores, executive control processes, and an episodic buffer that allows for communication between short- and long-term memory stores (Baddeley & Logie, 1999). Results indicated that only executive control processes significantly differentiated the psychotic and nonpsychotic bipolar groups, although visuospatial working memory differentiated both bipolar groups from controls. The results support the idea that some aspects of working memory performance are markers for psychosis, while others may be more general markers for bipolar disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
59.
60.
University classes in Mathematics are traditionally perceived to be uninspiring and devoid of active student–lecturer communication. Large undergraduate classes further compound the difficulty of engaging students and enabling viable student–lecturer feedback. At the Mathematics Education Centre, Loughborough University, some staff members have been using electronic voting systems (EVS) to enliven the classroom and enable large numbers of students to respond to questions in real time during class. In this paper, we present an evaluation case study, based on student perceptions, of the impact of EVS use on student learning and engagement. The results show that majority of students are hugely positive about the usefulness and overall advantageousness of EVS use in classes. Results also show that EVS use does increase the likelihood of students participating and engaging in class, as even students who do not view EVS as being particularly useful stated that they are more likely to participate in classes where EVS are used than otherwise. However, there seems to be no correlation between EVS use and improvement (or otherwise) in student grades.  相似文献   
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