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Insertion of flexible microprobes into the brain requires withstanding the compressive penetration force by the microprobes. To aid the insertion of the microprobes, most of the existing approaches use pushing mechanisms to provide temporary stiffness increase for the microprobes to prevent buckling during insertion into the brain. However, increasing the microprobe stiffness may result in acute neural tissue damage during insertion. Moreover, any late or premature removal of the temporary stiffness after insertion may lead to further tissue damage due to brain micromotion or inaccuracy in the microprobe positioning. In this study, a novel pneumatic-based insertion mechanism is proposed which simultaneously pulls and pushes a flexible microprobe toward the brain. As part of the brain penetration force in the proposed mechanism is supplied by the tensile force, the applied compressive force, which the microprobe must withstand during insertion, is lower compared with the existing approaches. Therefore, the microprobes with a critical buckling force less than the brain penetration force can be inserted into the brain without buckling. Since there is no need for temporary stiffness increment, neural tissue damage during the microprobe insertion will be much lower compared with the existing insertion approaches. The pneumatic-based insertion mechanism is modeled analytically to investigate the effects of the microprobe configuration and the applied air pressure on the applied tensile and compressive forces to the microprobe. Next, finite element modeling is conducted, and its analysis results not only validate the analytical results but also confirm the efficiency of the mechanism.

A study on the effectiveness of engineering education in the development of industry-ready graduate engineers was conducted among academics and industry experts of engineering disciplines who have relevant experience in work-integrated learning in Australia. The hypothesis was that embedding enhanced work-integrated learning into all study semesters has the increased possibility of developing industry-ready graduate engineers. This paper outlines the research outcomes and an enhanced work-integrated learning framework that might be helpful for improving the industry-readiness of graduating engineers. Based on the research results, the researchers propose the allocation of an appropriate level of work-integrated learning for each indicator of attainment component from the elements of Engineers Australia’s Stage I Competencies. The aim of this paper is to provide detailed recommendations for implementing an enhanced work-integrated model in Bachelor of Engineering programs in Australia. The authors also present the concept of curriculum development based on industry-integrated learning outcomes, as well as the campus and industry engagement model for enhanced work-integrated learning for the subjects of study in the Bachelor of Engineering program. This framework can be used globally as a reference for developing similar work-integrated learning models.

Crossbred steers [British x Continental x Bos Indicus; n = 1844; initial body weight (BW) = 248 ± 28 kg] were used to evaluate the effects of chromium propionate supplementation to calf-fed steers in a commercial feedyard on growth performance, carcass characteristics and health. Steers were blocked by initial BW; pens were assigned randomly to one of two dietary treatments within block. Treatments, replicated in 15 pens/treatment with 57 to 62 head per pen, included: 1) control, 0 mg supplemental Cr/kg dietary dry matter (DM) (CTL); 2) 0.50 mg supplemental Cr/kg dietary DM (chromium propionate; KemTRACE® Chromium 0.04%, Kemin Industries, Des Moines, IA) (CR). Due to inadvertent oversight, during the final 30 days on feed, CR cattle did not receive trace minerals, vitamins, an ionophore, antibiotic, or ractopamine-hydrochloride. Final BW, average daily gain (ADG) and DM intake did not differ among treatments (P ≥ 0.25). Gain efficiency was greater (P = 0.03) for CTL than CR (0.16 vs. 0.15). Hot carcass weight and dressing percentage were similar among treatments (P ≥ 0.19). Yield grade was higher for CR than CTL (2.44 vs. 2.27; P < 0.01); 12th-ribfat tended to be greater for CR than CTL (P = 0.09), and longissimus area was greater for CTL vs. CR (P < 0.01). Marbling score tended (P = 0.10) to be greater for CR than CTL. Steers fed CR tended (P = 0.07) to have a greater distribution of prime carcasses than CTL (1.9% vs. 0.07%), and percentage choice carcasses was higher for CR than CTL (67.34% vs. 61. 71%, P = 0.01). Respiratory morbidity (12.20%), and retreatment rate did not differ among treatments (P ≥ 0.20). In the absence of a beta-agonist, CR steers had higher quality carcasses, and similar ADG and HCW to CTL.

The laboratory instruction sheet (sometimes called a laboratory manual), together with the equipment used by students, is an essential resource for laboratory work. It has a direct influence over a...

Insertion of a microelectrode into the brain to record/stimulate neurons damages neural tissue and blood vessels and initiates the brain’s wound healing response. Due to the large difference between the stiffness of neural tissue and microelectrode, brain micromotion also leads to neural tissue damage and associated local immune response. Over time, following implantation, the brain’s response to the tissue damage can result in microelectrode failure. Reducing the microelectrode’s cross-sectional dimensions to single-digit microns or using soft materials with elastic modulus close to that of the neural tissue are effective methods to alleviate the neural tissue damage and enhance microelectrode longevity. However, the increase in electrical impedance of the microelectrode caused by reducing the microelectrode contact site’s dimensions can decrease the signal-to-noise ratio. Most importantly, the reduced dimensions also lead to a reduction in the critical buckling force, which increases the microelectrode’s propensity to buckling during insertion. After discussing brain micromotion, the main source of neural tissue damage, surface modification of the microelectrode contact site is reviewed as a key method for addressing the increase in electrical impedance issue. The review then focuses on recent approaches to aiding insertion of flexible microelectrodes into the brain, including bending stiffness modification, effective length reduction, and application of a magnetic field to pull the electrode. An understanding of the advantages and drawbacks of the developed strategies offers a guide for dealing with the buckling phenomenon during implantation.

British crossbred steers [n = 3074; initial body weight (BW) = 358 ± 37 kg] were used to evaluate the effects of chromium propionate supplementation to yearling steers in a commercial feedyard on growth performance, carcass characteristics and health. Steers were blocked by initial BW; pens were assigned randomly to one of two dietary treatments within block. Treatments, replicated in 15 pens/treatment with 75 to 135 head per pen, included: 1) control, 0 mg supplemental Cr/kg dietary dry matter (DM) (CTL); 2) 0.50 mg supplemental Cr/kg diet DM (chromium propionate; KemTRACE® Chromium 0.04%, Kemin Industries, Des Moines, IA) (CR). Final BW (638 vs. 641 kg.), average daily gain, (1.81 vs. 1.82 kg), DM intake (11.02 vs. 11.02 kg) and gain efficiency (0.164 vs 0.165) did not differ between CTL and CR, respectively (P ≥ 0.75). No differences among treatments for hot carcass weight (407 vs. 408 kg., CTL and CR, respectively), dressing percentage, longissimus muscle area, or yield grade were observed (P ≥ 0.15). Twelfth-rib fat thickness tended (P = 0.10) to be greater for CR vs. CTL (1.55 vs 1.29 cm, respectively). A trend (P = 0.10) for marbling score to be higher for CR vs. CTL was detected (452 vs. 440, respectively). Distribution of quality grade was similar between CR and CTL; 1.52% of carcasses graded prime (P =0.68), and 87.2% of carcasses graded choice (P = 0.68). Respiratory morbidity was low (1.93%) and not different among treatments (P = 0.20); likewise, there was no difference in respiratory treatment rates between treatments (P ≥ 0.18). Supplementing Cr to high-performing yearling steers did not alter growth performance, carcass characteristics or health outcomes.

Maternal undernutrition during pregnancy followed by ad libitum access to nutrients during postnatal life induces postnatal metabolic disruptions in multiple species. Therefore, an experiment was conducted to evaluate postnatal growth, metabolism, and development of beef heifers exposed to late gestation maternal nutrient restriction. Pregnancies were generated via transfer of in vitro embryos produced using X-bearing sperm from a single Angus sire. Pregnant dams were randomly assigned to receive either 100% (control; n = 9) or 70% (restricted; n = 9) of their total energy requirements from gestational day 158 to parturition. From post-natal day (PND) 301 until slaughter (PND485), heifers were individually fed ad libitum in a Calan gate facility. Calves from restricted dams were lighter than controls at birth (PPP>0.10). To assess pancreatic function, glucose tolerance tests were performed on PND315 and PND482 and a diet effect was seen with glucose area under the curve being greater (PPPP

Maternal nutrient restriction during pregnancy alters fetal programming, which modifies the growth and health of the offspring in postnatal life. In cattle, nutrient restriction during pregnancy can be a result of environmental or economic factors, but little is known about how it alters the physiology of the fetus and affects future reproductive or growth efficiency. This study used female monozygotic twins, produced through in vitro fertilization and embryo splitting, to determine the effect of moderate maternal nutrient restriction on fetal development. Recipient Angus cross heifers pregnant with one twin were fed a diet meeting 100% National Research Council (NRC) total energy requirements (n = 4; control), whereas recipient heifers pregnant with the second twin were fed at 70% of NRC total energy requirements (n = 4; restricted) from gestational day (GD) 158 to GD 265 in Calan gate feeders. Recipient heifers were killed at GD 265. Change in maternal metabolic body weight was greater from zero in restricted heifers than controls (P0.05); restricted heifers lost weight during the nutrient restriction period. There was no difference in last rib back fat or rib eye area between groups (P0.10). There was no difference in fetal weight, uterine weight, or total placentome weight between groups (P0.10). The pancreas weight was reduced in restricted fetuses compared with control fetuses (P0.01), but there were no other differences in fetal organ weights (P0.10). Plasma insulin concentrations were reduced in restricted fetuses compared with controls (P0.01), but there was no effect of maternal diet on plasma glucose or glucagon concentrations in the fetus (P0.10). Histological analyses of the fetal pancreas revealed no differences in endocrine cell number or localization. Results indicate that a modest late gestation nutritional restriction impairs development of the fetal pancreas in the cow. Additional research will be needed to determine if these developmental changes lead to altered glucose and insulin homeostasis in the adult.

It has long been known that in individual wood fibers, the tensile mechanical properties are heavily determined by the nature of the cellulose chains in the fibers. Both elastic tensile modulus and strength are directly related to the fibril angle, which is the steepness with which the cellulose chains wind their way around the fiber in the secondary wall of the middle layer, named the S2 layer. Classic work from the 1970s measured modulus and strength in wood fibers as a function of the fibril angle and compared the results with theoretical models. The measurements were hampered by the presence of defects in the fibers, some which occurred naturally and others which resulted from pulp processing. In this study, we performed more accurate measurements of strength and modulus in single fibers of radiata pine by loading the fibers in cycles, gradually pulling some of the defects out of the fibers in an attempt to obtain defect-free values of modulus and strength. We then plotted these properties against measured fibril angle and compared our results with theoretical models. The results show that even when the fiber had reached maximum load before fracture, at a given value of fibril angle, it still had a measured modulus that is around half the theoretically expected value. The results suggest that the load required to fully remove defects from the fibers may be larger than the fibers can bear before fracturing.

Gestational nutrient restriction causes epigenetic and phenotypic changes that affect multiple physiological processes in the offspring. Gonadotropes, the cells in the anterior pituitary that secrete luteinizing hormone (LH) and follicle-stimulating hormone (FSH), are particularly sensitive to nutritional changes during fetal development. Our objective herein was to investigate the effects of gestational nutrient restriction on LH protein content and number of gonadotropes in the fetal bovine pituitary. We hypothesized that moderate nutrient restriction during mid to late gestation decreases pituitary LH production, which is associated with a reduced number of gonadotropes. Embryos were produced in vitro with X-bearing semen from a single sire then split to generate monozygotic twins. Each identical twin was transferred to a virgin dam yielding four sets of female twins. At gestational d 158, the dams were randomly assigned into two groups, one fed 100% NRC requirements (control) and the other fed 70% of NRC requirements (restricted) during the last trimester of gestation, ensuring each pair of twins had one twin in each group. At gestational d 265, the fetuses (n = 4/group) were euthanized by barbiturate overdose, and the pituitaries were collected. Western blots were performed using an ovine LH-specific antibody (Dr. A.F. Parlow, NIDDK). The total LH protein content in the pituitary tended to be decreased in the restricted fetuses compared to controls (P < 0.10). However, immunohistochemistry analysis of the pituitary did not reveal any significant changes in the total number of LH-positive cells (control = 460±23 cells/0.5 mm2; restricted = 496±45 cells/0.5 mm2, P = 0.58). In conclusion, while maternal nutrient restriction during gestation resulted in a trend of reduced LH content in the fetal pituitary, immunohistological findings suggest that these changes are likely related to the individual potential of each gonadotrope to produce LH, rather than alterations in cell differentiation during fetal development.

The rapid advancement of technology, including the internet of things (IoT), industry 4.0, and smart cities, revealed an excess need for career-ready graduates. It is expected that a career-ready graduate is technically competent and possess professional skills acquired via the experiential learning incorporated into the curriculum. But the gap exists with the learners understanding of requirements and opportunities associated with graduate employability. In this research, we focus on evaluating the learners&rsquo, experiences, expectations, and perceptions of graduate employability in an engineering curriculum. In this research, the interpretations of students on the graduate employability and the extent of influence that exists based on the learning outcomes of the graduate course are examined. The gaps between the academic environment and graduate employability awareness are highlighted. Later, a national language processing-based sentiment analyzer is used to evaluate the student&rsquo, s perceptions. Results from the analysis portrayed that the different levels of expectation and experiences that prevailed in the graduate course based on the conceptual idea of graduate employability need substantial focus in future curriculum development.

The Committee on Polymer Education (PolyEd) had its initial planning meeting in 1974. The Intersociety Polymer Education Council (IPEC) has been active since 1990 as an outgrowth of PolyEd. Because of the activities of PolyEd and IPEC, basic polymer concepts have become a required part of undergraduate education and a more common topic in the curriculum for K–12 students. A brief history of polymer education is given. The current and future activities of PolyEd and IPEC are described.

1. Explain how site-specific crop management is used in production agriculture. 2. Understand how satellites are used to calculate position. 3. Explain how spatial data is used in crop management. 4. Be able to describe the difference between directed and grid soil sampling. 5. Understand how crop yield monitors are used to collect yield data.