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In this study, the optimization of the processing parameters and nanoparticle additive concentration in the cutting fluid for a milling process carried by Computer Numerical Control (CNC) was performed. Machining operations commonly present high wear on the cutting inserts. This translates into a limited tool lifespan, poor surface finish of the workpiece, and high energy consumption by the process, as well as high manufacturing costs. The nanoparticle (NP) selected for this study was a montmorillonite clay (MMT) due to being naturally occurring, inexpensive, and environmentally friendly. Nanolubricants were prepared with a MMT clay concentration of 0.2 and 0.3 wt%. A three level Box Behnken experimental design was performed in order to optimize the input parameters for milling of an AISI 1018 steel, such as: cutting speed, feed rate, depth of cut, and nanoparticle concentration in the cutting fluid. A total of 27 different combinations of these parameters were done by this method. Response characteristics investigated were: spindle load (related to power consumption), cutting insert radius (wear), and surface roughness (quality of the AISI 1018 steel work-piece). For the spindle load, it was found that NP addition had a significant effect. The results of the model for this response parameter indicate that the determination coefficient (R2) was 99%. The R2 of the model for the cutting insert radius was 93% and the results of the analysis of variance (ANOVA) showed that NPs had a significant effect when combined with the parameters of cutting speed and feed rate. The optimal range of values for the four input parameters that enhanced all three response characteristics were: a cutting speed of 1145–1182 rpm, depth of cut of 0.02–0.03 in, feed rate of 7–8 in/min, and MMT clay NP concentration of 0.13–0.15 wt%. The results obtained in this study demonstrate the benefit of green nanoadditives in cutting fluids and optimization of processing parameters for enhancing the efficiency of milling processes.

Macroscopic wear experiments were complemented by atomistic simulations to study the effect of nano- and micro-scale titanium dioxide particle lubricant additives on friction and wear. The size of the particles and initial roughness of the sliding surfaces were varied to characterize the interrelated effects of these two properties. Results from both experiments and simulations suggest that there is an optimal particle size that will minimize friction and wear for a given surface roughness. Analyses support a previously-proposed mechanism for particle-based additives in which the particles fill in valleys on the sliding surfaces. In this context, particles that are smaller than the characteristic roughness of the surfaces are most likely to perform this function.

Purpose To investigate process efficiency, we present a prospective investigation of the treatment planning phase of image-guided brachytherapy (BT) for cervical cancer using a specific checklist. Methods and Materials From October 2012 to January 2014, 76 BT procedures were consecutively performed. Prospective data on the CT-based treatment planning process was collected using a specific checklist which details the following steps: ( 1 ) dosimetry planning, ( 2 ) physician review start, ( 3 ) physician review time, ( 4 ) dosimetry processing, ( 5 ) physics review start, ( 6 ) physics review, and ( 7 ) procedural pause. Variables examined included the use of a pre-BT MRI, clinic duty conflicts, resident teaching, and the use of specific BT planners. Analysis was performed using descriptive statistics, t -test, and analysis of variance. Results Seventy-five prospectively gathered checklists comprised this analysis. The mean time for treatment planning was 95 minutes (med 94, std 18). The mean intervals in the above steps were ( 1 ) = 42, ( 2 ) = 5, ( 3 ) = 19, ( 4 ) = 10, ( 5 ) = 6, ( 6 ) = 13, and ( 7 ) = 26 minutes. There was no statistical difference in patients who had a pre-BT MRI. Resident teaching did not influence time, p = 0.17. Treatment planning time was decreased with a specific planner, p = 0.0015. Conclusions A skillful team approach is required for treatment planning efficiency in image-guided BT. We have found that the specific BT planners can have a significant effect on the overall planning efficiency. We continue to examine clinical and workflow-related factors that will enhance our safety and workflow process with BT.

Objective To compare the current breast cancer prevention and control Mexican standard with recommendations that health care professionals provide to women for breast self-exams, clinical breast exams and mammography, as well as health care professional knowledge of the risk factors for and main clinical signs of the disease. Methods In 2012, using a cross-sectional design, trained interviewers surveyed health care providers in a sample of 798 medical units, of which 756 corresponded to the first and second levels of medical care. One health care professional from each unit was interviewed for the study. The sampling method was systematic and representative of the national and regional levels. Relative frequencies and 95% confidence intervals (CI) were obtained using the weighting factor assigned to each medical unit. Results Regarding the indicator about recommendations provided to the population regarding early screening for and risk factors and clinical signs of breast cancer, the average number of health care professional responses in accordance with the Mexican standard was 10.7 (95% CI 10.0–11.4) out of a maximum of 28 points, which corresponds to an average rate of 38.2% of responses (95% CI 35.6–40.8). The percentage of correct answers increased in all areas of breast exam knowledge as training hours in the previous year increased. Conclusions Health care professionals are unaware of the current standards on breast cancer; therefore, these recommendations are not routinely translated into health care practice, which is a barrier to increasing the coverage of screening programs in health care services.

In this study, the effect of applying two different laser surface texturing (LST) patterns to cutting tools, as well as adding nanoparticles (NPs) to a lubricating cutting fluid in a machining process carried out in a Computer Numerical Control (CNC) machine were analyzed. Commonly, machining operations involve high wear of cutting inserts that limit their useful life, provide a poor surface finish of the workpiece and high energy consumption of the process, all of which increase production costs. The texturing patterns proposed were micro-circles and micro-channels and were applied on the rake face of the cutting tools. The NP selected for this study was a montmorillonite nanoclay (MMT) due to its ability to be produced naturally, and for being inexpensive and environmentally friendly. A concentration of 0.13 wt% was used for preparing the nanolubricant cutting fluids. An AISI 1018 steel was selected for the milling experiments at fixed machining parameters. The response variables investigated were: spindle load (related to power and energy consumption of the milling process), radius of the cutting insert (related to wear of the tool), and surface roughness of the steel plates (related to surface quality). The statistical and graphical analyses showed that for spindle load an improvement of up to 11% was found when LST of micro-channels and NPs where combined, whereas no effect was found when they were applied separately. For surface roughness, using tools with textured micro-channels or adding NPs to the cutting fluid were both beneficial individually. In the case of cutting insert radius both micro-circles and micro-channels reduced wear by 64% and 55%, respectively, compared to no LST. The results obtained in this study demonstrate that there is a synergistic effect found when combining LST patterns on cutting tools and adding NPs to the lubricant that increases the efficiency of the milling processes by reducing wear of the cutting tool, improving surface finish, and lowering spindle load.

Two-dimensional gel electrophoresis was used to locate potential neuronal death-related proteins in the moth Manduca sexta. Protein patterns of ganglia of pharate adult moths (taken prior to adult ecdysis) compared with protein patterns of one-day-old adults revealed reproducible changes in protein patterns. An acidic protein of approximately 40000 Da was present in all samples from adult moths undergoing neuronal death and essentially absent from pharate adult samples.

Pharmacological studies have suggested that neurotransmitter activity impinging on steroid-concentrating cells can affect the steroid receptor system within those cells, modifying behavioral responses to the hormone. The present experiments revealed that the alpha 1-noradrenergic antagonist prazosin, administered to ovariectomized rats at the time of each of two pulses of estradiol, inhibited the appearance of sexual receptivity. Prazosin also substantially reduced the levels of estrogen receptors within hypothalamic cell nuclei following an injection of estradiol. Manipulation of noradrenergic inputs into the hypothalamus by lesioning brain stem norepinephrine cell groups with 6-hydroxydopamine (6OHDA) also reduced the level of nuclear estrogen receptors following an injection of estradiol. Although this effect of 6OHDA lesions was observed in two separate experiments, in other experiments 6OHDA had no effect on estrogen receptors. In some instances, there was a positive correlation between nuclear estrogen receptor levels in the hypothalamus and the levels of norepinephrine. The results are consistent with the hypothesis that brain stem inputs to the hypothalamus are able to modulate neural responses to steroids and specifically that noradrenergic inputs are able to modulate neural responses to estradiol. However, there are additional undiscovered variables that preclude statements of a simple relationship between norepinephrine levels and estrogen receptor levels.

Controversy exists concerning mechanisms by which progesterone exerts central nervous system effects on behavior. Progesterone may affect behavior by genomic regulation of protein synthesis. Alternatively, it may work through nongenomic mechanisms, consistent with its short latency to act. In the present study, we have examined the hypothesis that progesterone facilitation of sexual behavior is correlated with modification of the synthesis of specific proteins in the ventromedial hypothalamus (VMH). Ovariectomized rats were treated with either estradiol (4 μg/kg at 0 and 18 h) or estradiol (at 0 and 18 h) plus progesterone (2 mg/kg at 37 h). 35S-labeled cysteine and methionine were bilaterally infused into the VMH at 37 h (the time of progesterone administration). Following 4 h of infusion, animals were tested for sexual behavior and sacrificed. Newly synthesized VMH proteins were separated by two-dimensional gel electrophoresis followed by fluorography. Analysis of approximately 660 spots/fluorogram in two independent replications indicated that no qualitative or quantitative changes in protein synthesis occurred in response to progesterone. In each replication statistical analysis suggested that the abundance of several proteins may have changed, but no specific proteins were changed in abundance in both replications. Within the range of this technique (10–100 kDa and 4.8–6.7 apparent pI) we found no evidence that progesterone causes alterations in VMH protein synthesis.

The present study examined effects of environmental complexity on the size of the superior colliculus, a subcortical structure involved in visuomotor functions. Long-Evans hooded rats raised together in a complex environment for 48 weeks were compared with their littermates housed in individual cages. The depth and area of the superficial gray layer of the superior colliculus were about 5–6% greater in the group from the complex environment, while the deeper layers of the superior colliculus showed no significant differences. The magnitude of the differences approached those reported for the neocortex, which has been considered to be distinctive in its morphological responsiveness to differential environmental complexity. The findings also extend previous observations that visual deprivation leads to shrinkage of the superficial gray layer and indicate that the morphology of this subcortical visual area is responsive to varying degrees of environmental stimulation.

Previous work has established that it is possible to enrich home-prepared tortillas with soy proteins by lime cooking of whole raw corn-soybean mixtures. Since tortillas are also extensively prepared in Mexico from limed corn flour, an investigation was carried out to determine if it were possible to enrich such flour by a similar procedure. The normal process for making tortilla flour was employed, except that In the lime cooking step, whole raw corn-soybean mixtures containing 10% soybeans were used in place of pure corn. Protein quantity and quality of the enriched flour were found to be increased as follows: protein content, from 9.2 to 12.6%, an increase of 36%; protein efficiency ratio (PER) from 1.45 to 2.62 (casein PER = 3.40), an increase of 81%. Heat treatment of the enriched flour was found to be adequate by the urease method, and a trained panel could not significantly distinguish between tortillas prepared from either flour. Finally, rancidity was not detected organoleptically in a sample of flour stored at room temperature for 12 months. Considering present costs of corn and soybeans in Mexico, it was calculated that use of whole raw soybeans as an enriching agent for tortilla flour at a 10% level would raise the cost of the flour by 5%, while use of defatted soy flour for the same purpose, and at an equivalent protein level, would raise the cost of the flour by 40%.