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The rf fluctuation effects on an uncompensated probe is theoretically and experimentally studied and assuming a Maxwellian distribution and sinusoidal plasma-potential oscillation, the electron temperature is reduced directly from an uncompensated Langmuir probe trace, by taking the natural logarithm of the electron current. This result is again brought to the attention, which shows that under certain discharge conditions it is not necessary to build any rf compensation in a Langmuir probe system.

The effects of electron current on a capacitive sheath are investigated by controlling this current with an additional dc bias on the electrode. The results have shown that the electron power absorption is more effective when the electron current is removed and the theoretical models have also shown a high harmonic content on the sheath voltage that is attenuated by removing the electron current.

To optimize first lactation and lifetime milk yield, growth benchmarks were established to help meet the appropriate growth objectives of breeding weight and age at an economically viable time and to achieve the optimum body size and composition at first calving. These guidelines provide a framework that helps to minimize overfeeding and, thus, potential overconditioning of heifers, which can lead to postpartum metabolic issues and reduced milk yield. Concerns still exist that mammary development is impaired when body weight gain exceeds a certain threshold, which would negatively affects milk yield. The objective of this review was to integrate concepts of nutrient requirements, body growth and composition, mammary development, and milk yield to provide a systems-based perspective on first-lactation milk differences that have been associated with mammary development. Work in the early 1980s described the effect of high energy intake on mammary development and the relationship with circulating growth hormone linked the relationship between prepubertal growth, mammary development, and future milk yield. The primary outcome of that research was to provide an intuitive mechanism to explain why rapid growth during the prepubertal phase resulted in reduced milk yield. The observation of reduced mammary development could be repeated in almost every experiment, leading to the conclusion that high energy intake and increased average daily gain reduced mammary development through altered hormone status or some signaling processes. However, further work that looked at mammary development over the entire prepubertal growth phase recognized that mammary development was not reduced by high energy intake, and instead accumulated at a constant rate; thus, overall mammary parenchymal growth was a function of the time to reach puberty and the associated signals to change from allometric mammary growth. The mammary gland, similar to most reproductive organs, grows in proportion to the size of the body and not in proportion to nutrient intake during the postweaning, prepubertal phase. First-lactation milk yield, mammary development, and body composition will be further discussed in the context of mechanisms and opportunities. [ABSTRACT FROM AUTHOR]

The effects of the external circuit on plasma instabilities in an inductive plasma source are investigated. The instabilities are found to be asymmetric with respect to the circuit input impedance. A simplified model of the antenna-plasma coupling provides an explanation of the asymetry. [ABSTRACT FROM AUTHOR]

The benefits of feeding elevated quantities of milk to dairy calves have been well established. However, there is a reluctance to adopt this method of feeding in commercial dairy production because of concerns around growth, health, and ruminal development during weaning. The objective of this study was to characterize the effect of an abrupt (0 d step-down) or gradual (12 d step-down) feeding scheme when calves are fed an elevated plane of nutrition (offered 1.35 kg of milk replacer/d). For this experiment, a total of 54 calves were randomly assigned to an abrupt or a gradual weaning protocol before weaning at 48 d of life. Calves were housed and sampled in individual pens for the duration of the experiment, and milk, starter, and straw intake were measured on a daily basis. Body weight was measured every 6 d, whereas blood, rumen fluid, and fecal samples were collected on d 36 (prestep-down), 48 (preweaning), and 54 (postweaning) of the experiment. Although the growth rates of the step-down calves were lower from d 37 to weaning (0.62 ± 0.04 vs. 1.01 ± 0.04 kg/d), the postweaning average daily gain was greater compared with the group that was abruptly weaned (0.83 ± 0.06 vs. 0.22 ± 0.06 kg/d). Total ruminal volatile fatty acid was greater in the step-down group on the day of weaning (d 48; 59.80 ± 2.25 vs. 45.01 ± 2.25 mmol), whereas the fecal starch percentage was lower during postweaning compared with the abruptly weaned calves (d 54; 3.31 ± 0.76 vs. 6.34 ± 0.76%). Analysis of the digestive tract of bull calves on d 55 revealed minimal differences between gross anatomy measurements of gut compartments as well as no morphological differences in rumen papillae development, yet the total mass of rumen when full of contents was larger in the step-down calves (7.83 ± 0.78 vs. 6.02 ± 0.78 kg). Under the conditions of this study, the results showcase the benefits of a step-down feeding strategy from an overall energy balance standpoint, due to increased adaptation of the gastrointestinal tract preweaning. [ABSTRACT FROM AUTHOR]

Performance of dairy cows can be influenced by early life nutrient supply. Adipose tissue is diet sensitive and an important component in that process as it is involved in the regulation of energetic, reproductive and immunological functions. However, it is not clear how early life nutrition alters the molecular regulation of adipose tissue in calves and potentially adult individuals. This study aimed at determining how differences in pre-weaning nutrient supply alter gene expression profiles and physiology in omental adipose tissue. A total of 12 female Holstein calves were fed two levels of milk replacer supply: a restricted amount of 11.72 MJ of metabolizable energy (ME) intake per day (n = 6) or an enhanced amount of 1.26 MJ ME intake per kg of metabolic body weight (BW0.75), resulting in supply from 17.58 to 35.17 MJ ME intake per day (n = 6). All calves had ad libitum access to a commercial calf starter and water. Analysis of the transcriptome profiles at 54 ± 2 days of age revealed that a total of 396 out of 19,968 genes were differentially expressed (DE) between groups (p < 0.001, FDR < 0.1). The directional expression of DE genes through Ingenuity Pathway Analysis showed that an enhanced nutrient supply alters adipose tissue physiology of pre-weaned calves. Several biological functions were increased (Z-score > +2), including Lipid Metabolism (Fatty Acid Metabolism), Cell Cycle (Entry into Interphase, Interphase, Mitosis and Cell Cycle Progression), Cellular Assembly and Organization (Cytoskeleton Formation and Cytoplasm Development) and Molecular Transport (Transport of Carboxylic Acid). These changes were potentially orchestrated by the activation/inhibition of 17 upstream regulators genes. Our findings indicate that adipose tissue of calves under an enhanced nutrient supply is physiologically distinct from restricted calves due to an increased development/expansion rate and also a higher metabolic activity through increased fatty acid metabolism., Competing Interests: The authors have declared that no competing interests exist. The commercial affiliation with Trouw Nutrition for the authors [LNL, FS, HB, JMT] does not alter our adherence to PLOS ONE policies on sharing data and materials.

This study presents the morphological and chemical modification of the cell structure of aerosolized Escherichia coli treated with a dielectric barrier discharge (DBD). Exposure to DBD results in severe oxidation of the bacteria, leading to the formation of hydroxyl groups and carbonyl groups and a significant reduction in amine functionalities and phosphate groups. Near edge x-ray absorption fine structure (NEXAFS) measurements confirm the presence of additional oxide bonds upon DBD treatment, suggesting oxidation of the outer layer of the cell wall. Electron microscopy images show that the bacteria undergo physical distortion to varying degrees, resulting in deformation of the bacterial structure. The electromagnetic field around the DBD coil causes severe damage to the cell structure, possibly resulting in leakage of vital cellular materials. The oxidation and chemical modification of the bacterial components are evident from the Fourier transform infrared spectroscopy and NEXAFS results. The bacterial reculture experiments confirm inactivation of airborne E. coli upon treating with DBD.

Background: Arteriovenous malformations (AVM) of the uterus are a rare but potential cause of recurrent pregnancy loss. Only four cases of uterine AVM have resulted in a live birth after conservative management. There is no previous report in which a combination of a müllerian anomaly and an AVM existed concomitantly., Case: A 33-year-old woman with a history of recurrent pregnancy loss was found to have a coexistent uterine AVM and a bicornuate uterus. The patient underwent arterial embolization and Strassman metroplasty and subsequently had a term pregnancy with a live birth., Conclusion: Management of uterine AVM should be individualized, taking into account the patient's desire for future fertility and the stability of her health at presentation.

Objective: To study levels of proinflammatory cytokines in pleural fluid during the severe ovarian hyperstimulation syndrome (OHSS)., Design: Case report., Setting: Tertiary academic medical center., Patient(s): A 35-year-old female with a 6-year history of unexplained infertility on menotropin therapy and 28 healthy normal controls., Intervention(s): Thoracentesis for severe pleural effusion and venipunctures., Main Outcome Measure(s): Interleukin-1 beta (IL-beta), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha) levels were measured by ELISA and compared between pleural effusion and serum from normal controls., Result(s): Pleural effusion IL-1 beta and IL-6 levels were higher than serum. Interleukin-6 levels were elevated particularly in pleural effusion (1,961.89 pg/mL) compared with serum (3.9 +/- 0.41 pg/mL)., Conclusion(s): Our results confirm the high cytokine levels observed in OHSS. Cytokines have been implicated in capillary permeability, extravasation of fluid, oliguria, and shock. We have postulated that these mediators are released from the corpora lutea into the peritoneum and systemic circulation. Alternatively, the presence of high cytokine levels in pleural fluid maybe the result of diaphragmatic defects, which allow for the migration of ascites into the pleural space.