The precision of strip flatness depends on several factors; wear of rolls is one of the main variables that have influence on the surface quality of the strip. The wear of the roils represents a complex friction condi...The precision of strip flatness depends on several factors; wear of rolls is one of the main variables that have influence on the surface quality of the strip. The wear of the roils represents a complex friction condition, sometimes the wear in the backup roll is not analyzed because the strip is not in contact with the backup roll; however, after several campaigns of rolling, the wear in the backup roll becomes dangerous because the pressure distribution is not uniform. Investigation of mechanism of the surface deterioration of the backup roll for the hot strip rolling is very important for the development of the automatic strip shape control system used in hot strip mills. A mathematical model is developed considering the Hertzian pressure distribution between two cylinders with parallel axes. It is used in real time for calculating the wear in the backup roll and in this manner take deci- sions for preventing finished product reworking or damage of equipments, which result in accidents caused by excessive wear in the backup rolls.展开更多
Background: Nonagenarians are uncommon in our population. The study aim was to profile physical mobility, declared health problems, hypertension and diabetes frequency, awareness, treated and good control in urban low...Background: Nonagenarians are uncommon in our population. The study aim was to profile physical mobility, declared health problems, hypertension and diabetes frequency, awareness, treated and good control in urban low-income elders. Method: The study had cross-sectional design in population sample. Subjects were urban men and women older than 59 years at the medium low income stratum at a developing country. Survey was carried out from October 2008 to October 2009. All elder dwellers in randomly selected houses were surveyed;clinical exam after consent. Good Control: Systolic/Diastolic Results: There were 162 elders, 53 (32.7%) were male, 99 (61.1%) were younger than 70 years. Forty nine (30.2%) had impaired mobility;among them 20 (55.6%) were bed or home restricted, and 29 (44.4%) needed help to go out. Unstable health condition was found in 36 (22.2%), with significantly more men 19 (52.8%) vs 34 (27.0%), X2 = 8.5, df1, P 0.05. The frequency, proportions for: known diagnosis, on treatment, and good control were 75 (69.4%), 55 (73.3%), 45 (60.0%) and 12 of 45 (26.7%) for hypertension;53 (49.1%), 47 (88.7%), 42 (79.2%) and 9 of 42 (21.4%) for diabetes. The most frequent unstable conditions were cardiovascular. Conclusions: Data suggest unstable health no association with the oldest old. The small proportion in good control of Diabetes and/or hypertension could explain the large frequency of elders with unstable health and prevention of reaching nonagenarian age.展开更多
A sample of 80 secondary students was required to take an information integration theory study to explore judgment formation toward health risk behavior regarding obesity. Here, twelve social scenarios containing a si...A sample of 80 secondary students was required to take an information integration theory study to explore judgment formation toward health risk behavior regarding obesity. Here, twelve social scenarios containing a simulated actor were implemented (vignettes) having in mind a three factor experimental factor design (diet, weight and physical activity). Subjects had to read each vignette and provide an answer by marking ten points anchored scale to provide judgment on actors’ possible health risk outcome. Results showed that study participants valuated diet as the most relevant factor, followed by the description of weight and finally followed by the factor of physical activity. They impose systematic thinking to integrate different sources of information provided by factor manipulation in the vignettes by using a cognitive summative rule. Implications of this study result to clinical intervention in obesity as well as for theoretical considerations of cognitive models of health risk behavior are discussed in the present article.展开更多
Gravity data are sensitive to local vertical offsets across high-angle faults, where rocks with different densities are juxtaposed. Yet high densities in some Mesozoic sedimentary rocks just above the basement may sme...Gravity data are sensitive to local vertical offsets across high-angle faults, where rocks with different densities are juxtaposed. Yet high densities in some Mesozoic sedimentary rocks just above the basement may smear out the subtle gravity signatures of basement faults. At this study the gravity data processing tends to avoid ill-described “black-box” techniques. The study area is situated in the Palomas site, Cuatrociénegas region, Coahuila, NE Mexico. The San Marcos Fault is at least 300 km long and has WNW-ESE trend from the central part of Nuevo León State through Coahuila, and finally to the eastern part of Chihuahua State. Gravimetric data shows that the lowest values of free air and Bouguer anomalies are in the southern part of the area, and the highest values are in the western and central part of the area. Between these parts exists a zone of high horizontal gravity gradient. Configuration of linear elements of gravity field (gradient zones) delimited the San Marcos Fault in the San Marcos valley below thickness of recent sedimentary cover. Two density models were carried out, which showed that the Cretaceous rocks are in discordant contact with the Paleo- zoic rocks that can be related to the San Marcos Fault. The density was determinate using to Nettleton’s method, which results highlight the presence of the San Marcos Fault. Density models showed that the Quaternary sediments are in direct contact with the San Marcos Fault.展开更多
During earthquakes and strong underground explosions it is possible to observe two different effects. The first one is connected with the destruction of media, and this causes acoustic and later hybrid acoustic-electr...During earthquakes and strong underground explosions it is possible to observe two different effects. The first one is connected with the destruction of media, and this causes acoustic and later hybrid acoustic-electromagnetic waves in an epicenter in the atmosphere and in the ionosphere. Another one is connected with cracks in crystals of rocks, which seems more interesting, because it is possible to recognize the natural earthquakes and industrial explosions. In the first effects due to nonlinear elastic modules the acoustic waves move through the lithosphere and transform their spectra from VLF (very low frequencies ~ 1 - 10 kHz) at the depth of about 30 km into the lower part of ELF (extremely low frequencies, ~ 3 Hz - 1 kHz) on the Earth’s surface, then they pass the atmosphere and penetrate into the ionosphere. During the nonlinear acoustic passage through the atmosphere and the ionosphere, the spectrum transforms from ELF into ULF (ultra low frequencies, < 1 Hz) range. In this review article the classification of spectrum and analysis of two cases of the destruction of rocks in the lithosphere is presented. The rocks possess piezoelectric and piezomagnetic properties. In this case the electromagnetic emission is excited by the fracturing in plates of crystals. The difference of emission from piezoelectric and magnetic plates in cases of industrial explosions and natural seismic events including volcanic phenomena gives a possibility to analyze the method of its identification. The consideration is based on the model of the plate of a finite size with an uniformly moving crack.展开更多
In additive manufacturing(also known as 3D printing),a layer-by-layer buildup process is used for manufacturing parts.Modern laser 3D printers can work with various materials including metal powders.In particular,mixi...In additive manufacturing(also known as 3D printing),a layer-by-layer buildup process is used for manufacturing parts.Modern laser 3D printers can work with various materials including metal powders.In particular,mixing various-sized spherical powders of titanium alloys is considered most promising for the aerospace industry.To achieve desired mechanical properties of the final product,it is necessary to maintain a certain proportional ratio between different powder fractions.In this paper,a modeling approach for filling up a rectangular 3D volume by unequal spheres in a layer-by-layer manner is proposed.A relative number of spheres of a given radius(relative frequency)are known and have to be fulfilled in the final packing.A fast heuristic has been developed to solve this special packing problem.Numerical results are compared with experimental findings for titanium alloy spherical powders.The relative frequencies obtained by using the imposed algorithm are very close to those obtained by the experiment.This provides an opportunity for using a cheap numerical modeling instead of expensive experimental study.展开更多
Background: This document includes recommendations and guidelines issued by a group of Mexican researchers and specialists gathered in the First National Colloquium for the Diagnosis and Management of Chronic Myeloid ...Background: This document includes recommendations and guidelines issued by a group of Mexican researchers and specialists gathered in the First National Colloquium for the Diagnosis and Management of Chronic Myeloid Leukaemia (CML) by initiative of Instituto Nacional de Cancerología and with the support of the Leukaemia Department of the MD Anderson Cancer Center. Mexico lacks of updated information taken from its own reality on the diagnosis and treatment of CML and other haematological disorders;besides, there are no national guidelines. Aim: To publish a consensus document with guidelines for the management of CML adjusted to the national environment and overall characteristics. Method: The participants answered a DELPHI questionnaire about the overall aspects of the disease, aiming to target controversial topics, discuss them in the colloquium, and to agree on the best ones. After those meetings, a final document was drawn up. Results: The group presents recommendations for definition, diagnosis, prognosis, monitoring, and treatment of CML in Mexico. Conclusions: Having consensus guidelines for the clinical management of CML in our country will enable the consensual practice of Mexican specialists regarding the clinical approach to CML, as well as optimize the resources which allow the rational planning of the medical care strategies.展开更多
文摘The precision of strip flatness depends on several factors; wear of rolls is one of the main variables that have influence on the surface quality of the strip. The wear of the roils represents a complex friction condition, sometimes the wear in the backup roll is not analyzed because the strip is not in contact with the backup roll; however, after several campaigns of rolling, the wear in the backup roll becomes dangerous because the pressure distribution is not uniform. Investigation of mechanism of the surface deterioration of the backup roll for the hot strip rolling is very important for the development of the automatic strip shape control system used in hot strip mills. A mathematical model is developed considering the Hertzian pressure distribution between two cylinders with parallel axes. It is used in real time for calculating the wear in the backup roll and in this manner take deci- sions for preventing finished product reworking or damage of equipments, which result in accidents caused by excessive wear in the backup rolls.
文摘Background: Nonagenarians are uncommon in our population. The study aim was to profile physical mobility, declared health problems, hypertension and diabetes frequency, awareness, treated and good control in urban low-income elders. Method: The study had cross-sectional design in population sample. Subjects were urban men and women older than 59 years at the medium low income stratum at a developing country. Survey was carried out from October 2008 to October 2009. All elder dwellers in randomly selected houses were surveyed;clinical exam after consent. Good Control: Systolic/Diastolic Results: There were 162 elders, 53 (32.7%) were male, 99 (61.1%) were younger than 70 years. Forty nine (30.2%) had impaired mobility;among them 20 (55.6%) were bed or home restricted, and 29 (44.4%) needed help to go out. Unstable health condition was found in 36 (22.2%), with significantly more men 19 (52.8%) vs 34 (27.0%), X2 = 8.5, df1, P 0.05. The frequency, proportions for: known diagnosis, on treatment, and good control were 75 (69.4%), 55 (73.3%), 45 (60.0%) and 12 of 45 (26.7%) for hypertension;53 (49.1%), 47 (88.7%), 42 (79.2%) and 9 of 42 (21.4%) for diabetes. The most frequent unstable conditions were cardiovascular. Conclusions: Data suggest unstable health no association with the oldest old. The small proportion in good control of Diabetes and/or hypertension could explain the large frequency of elders with unstable health and prevention of reaching nonagenarian age.
文摘A sample of 80 secondary students was required to take an information integration theory study to explore judgment formation toward health risk behavior regarding obesity. Here, twelve social scenarios containing a simulated actor were implemented (vignettes) having in mind a three factor experimental factor design (diet, weight and physical activity). Subjects had to read each vignette and provide an answer by marking ten points anchored scale to provide judgment on actors’ possible health risk outcome. Results showed that study participants valuated diet as the most relevant factor, followed by the description of weight and finally followed by the factor of physical activity. They impose systematic thinking to integrate different sources of information provided by factor manipulation in the vignettes by using a cognitive summative rule. Implications of this study result to clinical intervention in obesity as well as for theoretical considerations of cognitive models of health risk behavior are discussed in the present article.
文摘Gravity data are sensitive to local vertical offsets across high-angle faults, where rocks with different densities are juxtaposed. Yet high densities in some Mesozoic sedimentary rocks just above the basement may smear out the subtle gravity signatures of basement faults. At this study the gravity data processing tends to avoid ill-described “black-box” techniques. The study area is situated in the Palomas site, Cuatrociénegas region, Coahuila, NE Mexico. The San Marcos Fault is at least 300 km long and has WNW-ESE trend from the central part of Nuevo León State through Coahuila, and finally to the eastern part of Chihuahua State. Gravimetric data shows that the lowest values of free air and Bouguer anomalies are in the southern part of the area, and the highest values are in the western and central part of the area. Between these parts exists a zone of high horizontal gravity gradient. Configuration of linear elements of gravity field (gradient zones) delimited the San Marcos Fault in the San Marcos valley below thickness of recent sedimentary cover. Two density models were carried out, which showed that the Cretaceous rocks are in discordant contact with the Paleo- zoic rocks that can be related to the San Marcos Fault. The density was determinate using to Nettleton’s method, which results highlight the presence of the San Marcos Fault. Density models showed that the Quaternary sediments are in direct contact with the San Marcos Fault.
文摘During earthquakes and strong underground explosions it is possible to observe two different effects. The first one is connected with the destruction of media, and this causes acoustic and later hybrid acoustic-electromagnetic waves in an epicenter in the atmosphere and in the ionosphere. Another one is connected with cracks in crystals of rocks, which seems more interesting, because it is possible to recognize the natural earthquakes and industrial explosions. In the first effects due to nonlinear elastic modules the acoustic waves move through the lithosphere and transform their spectra from VLF (very low frequencies ~ 1 - 10 kHz) at the depth of about 30 km into the lower part of ELF (extremely low frequencies, ~ 3 Hz - 1 kHz) on the Earth’s surface, then they pass the atmosphere and penetrate into the ionosphere. During the nonlinear acoustic passage through the atmosphere and the ionosphere, the spectrum transforms from ELF into ULF (ultra low frequencies, < 1 Hz) range. In this review article the classification of spectrum and analysis of two cases of the destruction of rocks in the lithosphere is presented. The rocks possess piezoelectric and piezomagnetic properties. In this case the electromagnetic emission is excited by the fracturing in plates of crystals. The difference of emission from piezoelectric and magnetic plates in cases of industrial explosions and natural seismic events including volcanic phenomena gives a possibility to analyze the method of its identification. The consideration is based on the model of the plate of a finite size with an uniformly moving crack.
文摘In additive manufacturing(also known as 3D printing),a layer-by-layer buildup process is used for manufacturing parts.Modern laser 3D printers can work with various materials including metal powders.In particular,mixing various-sized spherical powders of titanium alloys is considered most promising for the aerospace industry.To achieve desired mechanical properties of the final product,it is necessary to maintain a certain proportional ratio between different powder fractions.In this paper,a modeling approach for filling up a rectangular 3D volume by unequal spheres in a layer-by-layer manner is proposed.A relative number of spheres of a given radius(relative frequency)are known and have to be fulfilled in the final packing.A fast heuristic has been developed to solve this special packing problem.Numerical results are compared with experimental findings for titanium alloy spherical powders.The relative frequencies obtained by using the imposed algorithm are very close to those obtained by the experiment.This provides an opportunity for using a cheap numerical modeling instead of expensive experimental study.
文摘Background: This document includes recommendations and guidelines issued by a group of Mexican researchers and specialists gathered in the First National Colloquium for the Diagnosis and Management of Chronic Myeloid Leukaemia (CML) by initiative of Instituto Nacional de Cancerología and with the support of the Leukaemia Department of the MD Anderson Cancer Center. Mexico lacks of updated information taken from its own reality on the diagnosis and treatment of CML and other haematological disorders;besides, there are no national guidelines. Aim: To publish a consensus document with guidelines for the management of CML adjusted to the national environment and overall characteristics. Method: The participants answered a DELPHI questionnaire about the overall aspects of the disease, aiming to target controversial topics, discuss them in the colloquium, and to agree on the best ones. After those meetings, a final document was drawn up. Results: The group presents recommendations for definition, diagnosis, prognosis, monitoring, and treatment of CML in Mexico. Conclusions: Having consensus guidelines for the clinical management of CML in our country will enable the consensual practice of Mexican specialists regarding the clinical approach to CML, as well as optimize the resources which allow the rational planning of the medical care strategies.
