Background: Providing appropriate clinical placement has become increasingly difficult over the past several years. To meet the need, schools of nursing are using simulation laboratory experiences in place of direct p...Background: Providing appropriate clinical placement has become increasingly difficult over the past several years. To meet the need, schools of nursing are using simulation laboratory experiences in place of direct patient care. The COVID-19 pandemic pushed many students out of patient care environments and into the simulation laboratory. Methods: Repeating the research done in 2015, a qualitative case study design and the constructivist theory were again used. Recently graduated registered nurses were interviewed to answer the research questions: How do recent graduates of registered nurse (RN) education programs view the simulation lab experiences from nursing school, and what changes were made to your simulation experiences as a result of COVID-19? Results: Eight participants completed virtual or survey interviews. The data were coded and grouped into the same five themes from the previous research. The data revealed that there have not been significant changes in perceived simulation experiences in the past seven years. Conclusions: The recently graduated nurse has valuable insight regarding the efficacy of simulation laboratory experiences in preparation for real-world nursing. This insight can be used by schools of nursing to design effective simulation experiences.展开更多
Stem cells derived from adult tissues have long been consideredmultipotent, able to differentiate into a limited number of cell typesfound in their tissue of origin. Embryonic stem cells, in contrast,are pluripotent, ...Stem cells derived from adult tissues have long been consideredmultipotent, able to differentiate into a limited number of cell typesfound in their tissue of origin. Embryonic stem cells, in contrast,are pluripotent, which may differentiate into almost all cell types.With the ability to create induced pluripotent stem cells from somaticcells now available, the properties of multipotent stem cellsare being re-evaluated. If adult cells may be reverted to pluripotentstem cells, can multipotent stem cells also be manipulated towardspluripotency? Advancements in biotechnology now allow for bettermethods to investigate stem cell plasticity, such as the relativeinfluence of external versus intrinsic factors on cell fate. Recentstudies indicate that adult neural stem cells (NSCs) demonstrategreater plasticity under certain conditions, resulting in the derivationof a variety of cell types including muscle, hematopoietic, andepithelial cells. This suggests that NSCs may provide a potentialsource of rare cell types for clinical application as an alternative toembryonic stem cells. Producing rare cell types from NSCs ratherthan embryonic stem cells avoids the ethical issues surrounding theuse of this cell type. Further, NSCs may be an advantageous sourcecompared to induced pluripotent stem cells, which are difficult tocreate, expensive, and time-consuming to展开更多
Sports medicine practitioners must consider both physical and mental aspects of injury to fully rehabilitate the injured athlete. The psychological distress that follows injury has been well documented and calls for a...Sports medicine practitioners must consider both physical and mental aspects of injury to fully rehabilitate the injured athlete. The psychological distress that follows injury has been well documented and calls for a change in the rehabilitation of injured athletes[1-3]. With the recent emergence of sport psychology and the emphasis on competitive sport in the United States and展开更多
The brine shrimp Artemia exhibits two reproductive modes: 1) oviparity, producing diapause embryos;and 2) ovoviviparity, producing free-swimming nauplii. Previous studies have suggested the existence of a critical sta...The brine shrimp Artemia exhibits two reproductive modes: 1) oviparity, producing diapause embryos;and 2) ovoviviparity, producing free-swimming nauplii. Previous studies have suggested the existence of a critical stage that determines the reproductive mode. Physicochemical factors, such as photoperiod, temperature, and salinity, have been suggested to irreversibly aff ect the reproductive mode of oocytes during this critical stage. In this study, experiments were carried out using a photoperiod and temperature-sensitive parthenogenetic Artemia clone where maternal Artemia were shifted bidirectionally between ovoviviparity (18 h L:6 h D, 27℃) and oviparity (6 h L:18 h D, 19℃) culture conditions. In the main experiment ( Artemia shifted at six diff erent stages including the post-larva Ⅱ to adult Ⅱ), the reproductive mode of fi rst brood was converted when shifting was performed on post-larva Ⅱ and Ⅲ but was not converted when females were shifted after post-larva Ⅲ. A supplementary experiment further revealed that the reproductive mode of fi rst brood could be altered when shifting females at an "early phase of postlarva Ⅳ", characterized by a developing ovisac reaching the middle of the third abdominal segment, ventral spines, and some oocytes growing larger than the others. In both experiments, reproductive modes of the second brood were signifi cantly aff ected when the shifting was performed on post-larva Ⅳ. These results suggest that the critical stage for inducing oviparity and embryonic diapause is at the previtellogenic stage of oocytes, or at maternal "early phase of post-larva Ⅳ" for the first-brood off spring. During this stage, diff erential gene expression patterns of the two destined oocytes may be triggered by the token stimuli signals received by the oocytes.展开更多
Great Salt Lake(GSL),in northern Utah,is one of the largest lakes in the United States,with a total surface area of 4400 square kilometers.Arthropods constitute the most conspicuous and abundant animals inhabiting the...Great Salt Lake(GSL),in northern Utah,is one of the largest lakes in the United States,with a total surface area of 4400 square kilometers.Arthropods constitute the most conspicuous and abundant animals inhabiting the waters展开更多
One of the significant individualities of web-enhanced education is the lack of face-to-face interaction between the student and the educator. A consideration in web-enhanced education which has the probability for et...One of the significant individualities of web-enhanced education is the lack of face-to-face interaction between the student and the educator. A consideration in web-enhanced education which has the probability for ethical concern related to the physical disconnection of instructor and learner is the increased potential for academic dishonesty. This can present a dilemma for nurse educators involved in teaching a difficult curriculum, while it can be motivated to improve the quality and student outcomes related to safe patient-centered care. The most blatant consideration in this setting is plagiarism. This article reviews the various facets of this ethical issue and suggests proactive solutions for faculty and administration to deter academic dishonesty.展开更多
Background: Student test scores in the pediatric portion were at a national percentile rank of 30, which was concerning. It was theorized that the main contributor to this dilemma was that the majority of students wer...Background: Student test scores in the pediatric portion were at a national percentile rank of 30, which was concerning. It was theorized that the main contributor to this dilemma was that the majority of students were not able to have a pediatric clinical experience. Objective: The purpose of this project was to determine if the addition of pediatric simulation scenarios would have an impact on student learning as evidenced by end of level test scores. Method: A convenience sample (n = 100) of first year nursing students attending a university in the western United States participated in this project. This was a mixed methods study. A quasi-experimental design was used to compare test scores of both a non-intervention group and an intervention group of students. A 5 point Likert scale questionnaire was also using post-intervention to assess for changes in perceptions of self-confidence. Results: After implementation of the pediatric focused scenarios, students’ test scores increased to the 95th percentile. This 65 percentile increase is a significant change that suggests that pediatric simulation is effective in improving student exam performance. In addition, 81% of students also reported perceptions of increased levels of self-confidence after implementation of simulation scenarios. Conclusion: The findings suggest that simulation is an effective way to create alternative pediatric clinical experiences which can, in turn, increase student comprehension, test scores, and self-confidence.展开更多
The aim of this project was to examine if stress levels in Associate Degree (AD) nursing students can affect their perceived quality of care provided to patients. Nursing students experience tremendous amounts of stre...The aim of this project was to examine if stress levels in Associate Degree (AD) nursing students can affect their perceived quality of care provided to patients. Nursing students experience tremendous amounts of stress especially during their clinical experience. High levels of stress may affect the quality of patient care provided. This project implemented a stress reducing workshop and an instructional deep breathing compact disk (CD) to determine the effects of this intervention upon the stress levels of nursing students and the quality of care provided to patients. Nursing students completed a workshop where recognition of stress producing situations and effective ways to deal with them were discussed. Each student was provided with a CD containing a ten minute instructional deep breathing exercise which they were asked to listen to five times a week for six weeks. Nursing students were asked to complete Cohen’s Perceived Stress Scale (PSS) and the Student Perception of Quality of Patient Care Provided questionnaire prior to and after the implementation of the intervention. The results of the two questionnaires were compared to determine effectiveness of the stress reducing interventions. Using paired t scores, results demonstrated that students’ stress levels were decreased and student’s perception of quality of patient care provided improved after the stress reducing interventions.展开更多
This qualitative case study addressed recent graduates’ perception of the efficacy of simulation in registered nursing education. Finding clinical placement is one of the greatest challenges faced by schools of nursi...This qualitative case study addressed recent graduates’ perception of the efficacy of simulation in registered nursing education. Finding clinical placement is one of the greatest challenges faced by schools of nursing. One possible solution is to use high-fidelity simulation manikins to substitute for clinical experience. The research that exists regarding nursing simulation laboratory experiences focuses on improvement on exam scores and preparation for national board examinations. Very little research explores recently graduated nurse’s perceptions about the efficacy of simulation experiences. The conceptual framework for this study was the constructivist theory. This is a process of experience and reflection. It is a dynamic process that changes as the learner internalizes the experience. This study allowed the researcher to understand how recent graduates perceive the value of simulation experiences. Two research questions were identified: 1) How do recent graduates of registered nurse (RN) education programs view the simulation lab experiences from nursing school? 2) In what ways do the perceptions of simulation experiences differ between associate degree RN program graduates and bachelors program RN graduates? A case study research design was used to explore the perceptions of recently graduated RN about their experience with simulation. By interviewing recent graduates’ perceptions about their experiences with high-fidelity simulation in nursing school, and documenting their perceptions about the efficacy of those simulation experiences, information was obtained that might allow schools of nursing to increase the effectiveness of the simulation experience or validate its applicability in the real world setting.展开更多
We present the analysis of gold in plating solutions in the presence of several additive ions by portable X-ray fluorescence (XRF) revealing an optimum potassium gold cyanide concentration of 2 - 3 g/L for maximum cat...We present the analysis of gold in plating solutions in the presence of several additive ions by portable X-ray fluorescence (XRF) revealing an optimum potassium gold cyanide concentration of 2 - 3 g/L for maximum cathode efficiency. Additionally, we present the utility of XRF to determine the thickness of gold plated on copper substrates up to 6 microns.展开更多
Herbivory is common in mammals,yet our understanding of detoxification processes used by mammals to biotrans-form plant secondary compounds(PSCs)is limited.Specialist herbivores are thought to have evolved detoxifica-...Herbivory is common in mammals,yet our understanding of detoxification processes used by mammals to biotrans-form plant secondary compounds(PSCs)is limited.Specialist herbivores are thought to have evolved detoxifica-tion mechanisms that rely more heavily on energetically cheap Phase I biotransformation reactions to process high levels of PSCs in their diets.We explored this hypothesis by comparing the urinary metabolite patterns of two spe-cialist herbivores(genus Neotoma).Neotoma stephensi is an obligate specialist on one-seeded juniper(Juniperus monosperma).Neotoma lepida is a generalist forager across its range,yet populations in the Great Basin specialize on Utah juniper(J.osteosperma).While both juniper species have high levels of terpenes,the terpene profiles and quantities differ between the two.Individuals from both woodrat species were fed diets of each juniper in a cross-over design.Urine,collected over a 24-h period,was extracted and analyzed in an untargeted metabolomics approach using both GC-MS and HPLC-MS/MS.The obligate specialist N.stephensi excreted a unique pattern of Phase I metabolites when fed its native juniper,while N.lepida excreted a unique pattern of Phase II metabolites when fed its native juniper.Both woodrat species utilized the Phase II metabolic pathway of glucuronidation more heavily when consuming the more chemically diverse J.osteosperma,and N.stephensi utilized less glucuronida-tion than N.lepida when consuming J.monosperma.These results are consistent with the hypothesis that obligate specialists may have evolved unique and efficient biotransformation mechanisms for dealing with PSCs in their diet.展开更多
The Lie algebra sl_(2)(C)may be regarded in a natural way as a subalgebra of the infinite-dimensional Virasoro Lie algebra,so it is natural to consider connections between the representation theory of the two algebras...The Lie algebra sl_(2)(C)may be regarded in a natural way as a subalgebra of the infinite-dimensional Virasoro Lie algebra,so it is natural to consider connections between the representation theory of the two algebras.In this paper,we explore the restriction to sl_(2)(C)of certain induced modules for the Virasoro algebra.Specifically,we consider Virasoro modules induced from so-called polynomial subalgebras,and we show that the restriction of these modules results in twisted versions of familiar modules such as Verma modules and Whittaker modules.展开更多
Studies on habitat use have often helped explain observed variation in morphology,behavior and reproductive characteristics among populations within a single species.Here we analyze morphological and ecological charac...Studies on habitat use have often helped explain observed variation in morphology,behavior and reproductive characteristics among populations within a single species.Here we analyze morphological and ecological characteristics of individuals from the Sceloporus grammicus species complex from 7 different localities(CER,El Cerezo;PAC,Pachuca;HUI,Huichapan;EZA,Emiliano Zapata;SMR,San Miguel Regla;LMJ,La Mojonera;and LMZ,La Manzana)in the state of Hidalgo,and one locality(Cahuacán)in the State of Mexico.A canonical correspondence analysis(CCA)showed that females from PAC,EZA,LMZ,HUI,SMR and CAH populations use similar microhabitats characterized mostly by bare soil,in females from LMJ and CER use microhabitats characterized primarily by vegetation and rocks.Females were observed using 12 different types of perches.With regard to perch height use,the CCA showed that females from PAC,LMJ,LMZ,SMR,CER and CAH populations were correlated with height to nearest perch(HNP),in the rest of the females were not related to any perch use variable.In contrast,the CCA showed that males from PAC,LMJ and CAH were characterized by microhabitats with higher vegetal coverage,while males from LMZ and CER used microhabitats composed of bare soil,but males from HUI and SMR populations used microhabitats composed chiefly of bare soil and rocks.With respect to perch height use,the CCA showed that males from PAC,LMJ,EZA and LMZ were correlated with distance to the nearest perch,but the rest of the males were not correlated with any perch use variables.Males were observed in 9 different perch types.The males were larger than the females in all morphological variables analyzed.Moreover,in both sexes the snout-vent length is positively correlated with all morphological variables,and although both the slope and ordinate of the origin of all morphological variables were larger in males than females,the analysis of covariance indicated that there is no increase in the morphological variables with increasing SVL between sexes.Our results suggest that variation in habitat use and morphology among populations is an adaptive response(phenotypic plasticity)to the environmental conditions where these populations of Sceloporus grammicus occur.展开更多
文摘Background: Providing appropriate clinical placement has become increasingly difficult over the past several years. To meet the need, schools of nursing are using simulation laboratory experiences in place of direct patient care. The COVID-19 pandemic pushed many students out of patient care environments and into the simulation laboratory. Methods: Repeating the research done in 2015, a qualitative case study design and the constructivist theory were again used. Recently graduated registered nurses were interviewed to answer the research questions: How do recent graduates of registered nurse (RN) education programs view the simulation lab experiences from nursing school, and what changes were made to your simulation experiences as a result of COVID-19? Results: Eight participants completed virtual or survey interviews. The data were coded and grouped into the same five themes from the previous research. The data revealed that there have not been significant changes in perceived simulation experiences in the past seven years. Conclusions: The recently graduated nurse has valuable insight regarding the efficacy of simulation laboratory experiences in preparation for real-world nursing. This insight can be used by schools of nursing to design effective simulation experiences.
文摘Stem cells derived from adult tissues have long been consideredmultipotent, able to differentiate into a limited number of cell typesfound in their tissue of origin. Embryonic stem cells, in contrast,are pluripotent, which may differentiate into almost all cell types.With the ability to create induced pluripotent stem cells from somaticcells now available, the properties of multipotent stem cellsare being re-evaluated. If adult cells may be reverted to pluripotentstem cells, can multipotent stem cells also be manipulated towardspluripotency? Advancements in biotechnology now allow for bettermethods to investigate stem cell plasticity, such as the relativeinfluence of external versus intrinsic factors on cell fate. Recentstudies indicate that adult neural stem cells (NSCs) demonstrategreater plasticity under certain conditions, resulting in the derivationof a variety of cell types including muscle, hematopoietic, andepithelial cells. This suggests that NSCs may provide a potentialsource of rare cell types for clinical application as an alternative toembryonic stem cells. Producing rare cell types from NSCs ratherthan embryonic stem cells avoids the ethical issues surrounding theuse of this cell type. Further, NSCs may be an advantageous sourcecompared to induced pluripotent stem cells, which are difficult tocreate, expensive, and time-consuming to
文摘Sports medicine practitioners must consider both physical and mental aspects of injury to fully rehabilitate the injured athlete. The psychological distress that follows injury has been well documented and calls for a change in the rehabilitation of injured athletes[1-3]. With the recent emergence of sport psychology and the emphasis on competitive sport in the United States and
基金Supported by the Fundamental Research Funds for the Central Universities(No.201762017)the National Natural Science Foundation of China(No.31760626)
文摘The brine shrimp Artemia exhibits two reproductive modes: 1) oviparity, producing diapause embryos;and 2) ovoviviparity, producing free-swimming nauplii. Previous studies have suggested the existence of a critical stage that determines the reproductive mode. Physicochemical factors, such as photoperiod, temperature, and salinity, have been suggested to irreversibly aff ect the reproductive mode of oocytes during this critical stage. In this study, experiments were carried out using a photoperiod and temperature-sensitive parthenogenetic Artemia clone where maternal Artemia were shifted bidirectionally between ovoviviparity (18 h L:6 h D, 27℃) and oviparity (6 h L:18 h D, 19℃) culture conditions. In the main experiment ( Artemia shifted at six diff erent stages including the post-larva Ⅱ to adult Ⅱ), the reproductive mode of fi rst brood was converted when shifting was performed on post-larva Ⅱ and Ⅲ but was not converted when females were shifted after post-larva Ⅲ. A supplementary experiment further revealed that the reproductive mode of fi rst brood could be altered when shifting females at an "early phase of postlarva Ⅳ", characterized by a developing ovisac reaching the middle of the third abdominal segment, ventral spines, and some oocytes growing larger than the others. In both experiments, reproductive modes of the second brood were signifi cantly aff ected when the shifting was performed on post-larva Ⅳ. These results suggest that the critical stage for inducing oviparity and embryonic diapause is at the previtellogenic stage of oocytes, or at maternal "early phase of post-larva Ⅳ" for the first-brood off spring. During this stage, diff erential gene expression patterns of the two destined oocytes may be triggered by the token stimuli signals received by the oocytes.
基金provided by Weber State University’s Research, Scholarship, and Professional Growth Committee
文摘Great Salt Lake(GSL),in northern Utah,is one of the largest lakes in the United States,with a total surface area of 4400 square kilometers.Arthropods constitute the most conspicuous and abundant animals inhabiting the waters
文摘One of the significant individualities of web-enhanced education is the lack of face-to-face interaction between the student and the educator. A consideration in web-enhanced education which has the probability for ethical concern related to the physical disconnection of instructor and learner is the increased potential for academic dishonesty. This can present a dilemma for nurse educators involved in teaching a difficult curriculum, while it can be motivated to improve the quality and student outcomes related to safe patient-centered care. The most blatant consideration in this setting is plagiarism. This article reviews the various facets of this ethical issue and suggests proactive solutions for faculty and administration to deter academic dishonesty.
文摘Background: Student test scores in the pediatric portion were at a national percentile rank of 30, which was concerning. It was theorized that the main contributor to this dilemma was that the majority of students were not able to have a pediatric clinical experience. Objective: The purpose of this project was to determine if the addition of pediatric simulation scenarios would have an impact on student learning as evidenced by end of level test scores. Method: A convenience sample (n = 100) of first year nursing students attending a university in the western United States participated in this project. This was a mixed methods study. A quasi-experimental design was used to compare test scores of both a non-intervention group and an intervention group of students. A 5 point Likert scale questionnaire was also using post-intervention to assess for changes in perceptions of self-confidence. Results: After implementation of the pediatric focused scenarios, students’ test scores increased to the 95th percentile. This 65 percentile increase is a significant change that suggests that pediatric simulation is effective in improving student exam performance. In addition, 81% of students also reported perceptions of increased levels of self-confidence after implementation of simulation scenarios. Conclusion: The findings suggest that simulation is an effective way to create alternative pediatric clinical experiences which can, in turn, increase student comprehension, test scores, and self-confidence.
文摘The aim of this project was to examine if stress levels in Associate Degree (AD) nursing students can affect their perceived quality of care provided to patients. Nursing students experience tremendous amounts of stress especially during their clinical experience. High levels of stress may affect the quality of patient care provided. This project implemented a stress reducing workshop and an instructional deep breathing compact disk (CD) to determine the effects of this intervention upon the stress levels of nursing students and the quality of care provided to patients. Nursing students completed a workshop where recognition of stress producing situations and effective ways to deal with them were discussed. Each student was provided with a CD containing a ten minute instructional deep breathing exercise which they were asked to listen to five times a week for six weeks. Nursing students were asked to complete Cohen’s Perceived Stress Scale (PSS) and the Student Perception of Quality of Patient Care Provided questionnaire prior to and after the implementation of the intervention. The results of the two questionnaires were compared to determine effectiveness of the stress reducing interventions. Using paired t scores, results demonstrated that students’ stress levels were decreased and student’s perception of quality of patient care provided improved after the stress reducing interventions.
文摘This qualitative case study addressed recent graduates’ perception of the efficacy of simulation in registered nursing education. Finding clinical placement is one of the greatest challenges faced by schools of nursing. One possible solution is to use high-fidelity simulation manikins to substitute for clinical experience. The research that exists regarding nursing simulation laboratory experiences focuses on improvement on exam scores and preparation for national board examinations. Very little research explores recently graduated nurse’s perceptions about the efficacy of simulation experiences. The conceptual framework for this study was the constructivist theory. This is a process of experience and reflection. It is a dynamic process that changes as the learner internalizes the experience. This study allowed the researcher to understand how recent graduates perceive the value of simulation experiences. Two research questions were identified: 1) How do recent graduates of registered nurse (RN) education programs view the simulation lab experiences from nursing school? 2) In what ways do the perceptions of simulation experiences differ between associate degree RN program graduates and bachelors program RN graduates? A case study research design was used to explore the perceptions of recently graduated RN about their experience with simulation. By interviewing recent graduates’ perceptions about their experiences with high-fidelity simulation in nursing school, and documenting their perceptions about the efficacy of those simulation experiences, information was obtained that might allow schools of nursing to increase the effectiveness of the simulation experience or validate its applicability in the real world setting.
文摘We present the analysis of gold in plating solutions in the presence of several additive ions by portable X-ray fluorescence (XRF) revealing an optimum potassium gold cyanide concentration of 2 - 3 g/L for maximum cathode efficiency. Additionally, we present the utility of XRF to determine the thickness of gold plated on copper substrates up to 6 microns.
文摘Herbivory is common in mammals,yet our understanding of detoxification processes used by mammals to biotrans-form plant secondary compounds(PSCs)is limited.Specialist herbivores are thought to have evolved detoxifica-tion mechanisms that rely more heavily on energetically cheap Phase I biotransformation reactions to process high levels of PSCs in their diets.We explored this hypothesis by comparing the urinary metabolite patterns of two spe-cialist herbivores(genus Neotoma).Neotoma stephensi is an obligate specialist on one-seeded juniper(Juniperus monosperma).Neotoma lepida is a generalist forager across its range,yet populations in the Great Basin specialize on Utah juniper(J.osteosperma).While both juniper species have high levels of terpenes,the terpene profiles and quantities differ between the two.Individuals from both woodrat species were fed diets of each juniper in a cross-over design.Urine,collected over a 24-h period,was extracted and analyzed in an untargeted metabolomics approach using both GC-MS and HPLC-MS/MS.The obligate specialist N.stephensi excreted a unique pattern of Phase I metabolites when fed its native juniper,while N.lepida excreted a unique pattern of Phase II metabolites when fed its native juniper.Both woodrat species utilized the Phase II metabolic pathway of glucuronidation more heavily when consuming the more chemically diverse J.osteosperma,and N.stephensi utilized less glucuronida-tion than N.lepida when consuming J.monosperma.These results are consistent with the hypothesis that obligate specialists may have evolved unique and efficient biotransformation mechanisms for dealing with PSCs in their diet.
文摘The Lie algebra sl_(2)(C)may be regarded in a natural way as a subalgebra of the infinite-dimensional Virasoro Lie algebra,so it is natural to consider connections between the representation theory of the two algebras.In this paper,we explore the restriction to sl_(2)(C)of certain induced modules for the Virasoro algebra.Specifically,we consider Virasoro modules induced from so-called polynomial subalgebras,and we show that the restriction of these modules results in twisted versions of familiar modules such as Verma modules and Whittaker modules.
基金We thank CONACyT for the scholarship granted to the first author(ALM,#16301),and projects PROMEP/103.5/04/2751 and FOMIX-CONACYT-191908.
文摘Studies on habitat use have often helped explain observed variation in morphology,behavior and reproductive characteristics among populations within a single species.Here we analyze morphological and ecological characteristics of individuals from the Sceloporus grammicus species complex from 7 different localities(CER,El Cerezo;PAC,Pachuca;HUI,Huichapan;EZA,Emiliano Zapata;SMR,San Miguel Regla;LMJ,La Mojonera;and LMZ,La Manzana)in the state of Hidalgo,and one locality(Cahuacán)in the State of Mexico.A canonical correspondence analysis(CCA)showed that females from PAC,EZA,LMZ,HUI,SMR and CAH populations use similar microhabitats characterized mostly by bare soil,in females from LMJ and CER use microhabitats characterized primarily by vegetation and rocks.Females were observed using 12 different types of perches.With regard to perch height use,the CCA showed that females from PAC,LMJ,LMZ,SMR,CER and CAH populations were correlated with height to nearest perch(HNP),in the rest of the females were not related to any perch use variable.In contrast,the CCA showed that males from PAC,LMJ and CAH were characterized by microhabitats with higher vegetal coverage,while males from LMZ and CER used microhabitats composed of bare soil,but males from HUI and SMR populations used microhabitats composed chiefly of bare soil and rocks.With respect to perch height use,the CCA showed that males from PAC,LMJ,EZA and LMZ were correlated with distance to the nearest perch,but the rest of the males were not correlated with any perch use variables.Males were observed in 9 different perch types.The males were larger than the females in all morphological variables analyzed.Moreover,in both sexes the snout-vent length is positively correlated with all morphological variables,and although both the slope and ordinate of the origin of all morphological variables were larger in males than females,the analysis of covariance indicated that there is no increase in the morphological variables with increasing SVL between sexes.Our results suggest that variation in habitat use and morphology among populations is an adaptive response(phenotypic plasticity)to the environmental conditions where these populations of Sceloporus grammicus occur.