Pairing students on the wards: The effect on the clerkship learning environment.

BACKGROUND: Medical students are often paired together on clinical teams during their clerkships, but the effect of this practice is unknown. We conducted a survey study to determine student perceptions and attitudes regarding being paired on the same team with a classmate. METHODS: We conducted semi-structured interviews and utilized thematic analysis to develop themes for survey design. We then designed and administered a survey to the graduating class of 2018 at Harvard Medical School. RESULTS: One hundred students participated in the survey (60% response). The majority of students perceived that pairing impacted their clerkship evaluations. Pairing was perceived to positively impact learning, adjustment to the clerkship, enjoyment, wellness and the overall clerkship experience. However, stress related to grading and evaluation as well as competition for patients were cited as negative impacts. Students in our sample were split on their preferences for working alone or with another student on a clinical team. CONCLUSION: Student pairing is a common practice that affects the learning environment in clinical clerkships. Further study of interactions between students on medical teams as well as interventions to raise the positive value of pairing while limiting its negative impact may enhance the clerkship learning environment.

Dissipation kinetics and consumer risk assessment of novaluron + lambda-cyhalothrin co-formulation in cabbage.

Cabbage, one of the most popular vegetables in the world is infested by several insect-pests and diseases. Novaluron, a chitin synthesis inhibitor and lambda-cyhalothrin, a synthetic pyrethroid group insecticide are used to manage insect-pests on cabbage. The dissipation kinetics and risk assessment of combination formulation (novaluron 9.45% + lambda-cyhalothrin 1.9%) with different modes of action has not yet been investigated in cabbage. Multi-location supervised field trials were therefore, conducted in different agro-climatic regions of India for safety evaluation of the combination product. The co-formulation at the recommended (novaluron 750 g a.i. ha-1 + lambda-cyhalothrin 750 g a.i. ha-1) and double the recommended (novaluron 1500 g a.i. ha-1 + lambda-cyhalothrin 1500 g a.i. ha-1) dose was sprayed on the cabbage crop. The samples were extracted and cleaned up using a modified QuEChERS method, and the residues analyzed by GC-ECD and GC-MS. The half-life (t1/2) varied between 1.77 and 2.51 and 2.00-3.38 days for novaluron and 1.36-2.24 and 1.69-3.82 days for lambda-cyhalothrin in cabbage at respective doses. The Food Safety and Standards Authority of India (FSSAI) has set the MRL of 0.7 mg kg-1 for novaluron at PHI of 5 days, and no MRL is set for lambda-cyhalothrin in cabbage. On the basis of OECD MRL calculator, the MRLs of 0.6 and 1.5 mg kg-1 for novaluron and lambda-cyhalothrin, respectively were calculated at the respective doses at PHI of 3 days. Hazard quotient (HQ) <1, theoretical maximum daily intake (TMDI) < acceptable daily intake (ADI) and < maximum permissible intake (MPI), percent acute hazard index (% aHI) <1, and percent chronic hazard index (% cHI) <1 for both novaluron and lambda-cyhalothrin suggested that the combination formulation is safe and will not pose any dietary risk to the consumers. The study will be helpful to conduct risk assessment of other pesticides/combination pesticides on food crops on which their MRLs have not yet been fixed.

Synthesis, Crystallography, and Anti-Leukemic Activity of the Amino Adducts of Dehydroleucodine.

Dehydroleucodine is a bioactive sesquiterpene lactone. Herein, four dehydroleucodine amino derivatives were synthesized using the amines proline, piperidine, morpholine, and tyramine, and spectroscopic methods and single-crystal X-ray diffraction unambiguously established their structures. The cytotoxic activity of these compounds was evaluated against eight acute myeloid leukemia cell lines, and their toxicity to peripheral blood mononuclear cells was also determined. The proline adduct was the most active compound, it showed anti-leukemic activity, upregulated heme oxygenase 1 (HMOX1) and the primary stress-inducible isoform of the heath shock 70 kDa protein 1 (HSPA1A), and downregulated NFkB1 transcription, it was also found to be about 270 times more water soluble than dehydroleucodine.

Persistence, dissipation, and risk assessment of a combination formulation of trifloxystrobin and tebuconazole fungicides in/on tomato.

Multi-locational supervised field trials were conducted in different agro-climatic regions in India to study dissipation of trifloxystrobin and tebuconazole in tomato after spraying a combination formulation (trifloxystrobin 25% + tebuconazole 50%, 75WG) at recommended doses: (i) single (trifloxystrobin 87.5 g a.i. ha-1 + tebuconazole 175 g a.i. ha-1) and (ii) double (trifloxystrobin 175 g a.i. ha-1 + tebuconazole 350 g a.i. ha-1). Fruit samples were extracted with ethyl acetate using a modified QuEChERS method. The residues (parent fungicides + metabolite) were analyzed and confirmed by GC-ECD and GC-MS, respectively. The half-life (t1/2) of trifloxystrobin and tebuconazole in tomato varied from 1.08 to 1.72 and 1.13 -to 1.64 days at single; and 1.27 to 2.13 and 1.24 to 1.96 days at double dose, respectively. Since maximum residue limit (MRL) at pre-harvest interval (PHI) of 5 days is impractical, as tomato is usually harvested and consumed almost everyday after the last spray, the risk assessment was performed at minimum PHI of 1 day. Accordingly, on the basis of supervised field trial data and using OECD MRL calculator, MRL of 0.5 and 1.5 mg kg-1 at single dose were proposed for trifloxystrobin and tebuconazole in/on tomato, respectively.

Development, validation of QuEChERS-based method for simultaneous determination of multiclass pesticide residue in milk, and evaluation of the matrix effect.

Extraction and quantification of pesticide residue from the milk matrix at or below the established maximum residue limit (MRL) is a challenging task for both analytical chemists and the regulatory institutions to take corrective actions for the human health and safety. The main aim of the study is to develop a simple rapid and less expensive QuEChERS extraction and cleanup method for simultaneous analysis of 41 multiclass pesticide residue in milk by gas chromatography-electron capture detector (GC-ECD), followed by confirmation of the residues with gas chromatography-mass spectrometer (GC-MS). Effect of sorbent type, temperature, spiking concentration, matrix effect (ME), measurement uncertainty (MU), inter- and intra-assay repeatability, reproducibility of recovery, and trueness of the results were investigated to validate the effectiveness of the method. Limit of determination (LOD) and limit of quantitation (LOQ) for all the analytes ranged within 0.001-0.02 and 0.002-0.05 µg mL-1, respectively. The % recovery of all the pesticides ranged between 91.38 and 117.56% with relative standard deviation (RSD) below 2.79%. The MU for all the analytes was ≤29% of respective LOQs, and except for few pesticides, the ME was largely negative. The method fulfilled all the SANTE guidelines and thus can be extended for routine analysis of multiclass pesticide residue in milk.

ASSOCIATION OF AGE AT MENOPAUSE WITH POST-MENOPAUSAL SYMPTOMS, MENARCHE AGE AND OTHER REPRODUCTIVE FACTORS AMONG RURAL FEMALES IN SHIMLA, HIMACHAL PRADESH.

This study analysed the association between menopause, menarche and number of live births using cross-sectional primary data for 75 post-menopausal rural women from Shimla in the Indian state of Himachal Pradesh. The mean/median ages at menarche of the 75 women were 14.23/14 years, and those at menopause 45.35/45 years. There were no significant differences in these values between women in the age groups 40-55 and 56-65 years. Age at menopause was found to be significantly associated with age at menarche and maternal age at birth of the first and last child, but not with menopausal symptom severity score. The majority of the 75 post-menopausal women (70.7%) had very mild or no menopausal symptoms. Three principal components were identified that explained 72.43% of the underlying variation in menopausal symptoms.

Lead: Tiny but Mighty Poison.

The documentation of lead toxicity (plumbism) dates back to the times when man learnt its various applications. This versatile heavy metal is non-degradable and its ability to get accumulated in the body that goes undiagnosed, makes it a serious environmental health hazard. Lead is now known to affect almost every organ/tissue of the human body. With irreversible effects on neurobiological development of young children and foetus, its toxicity has lasting implications on the human life. Outlining the symptoms, diagnosis and treatment therapy for lead poisoning, the present review elaborates the pathophysiological effects of lead on various organs. This will be of immense help to the health professionals so as to inculcate a better understanding of the lead poisoning which otherwise is asymptomatic. With chelation therapy being the classic path of treatment, new strategies are being explored as additive/adjunct therapy. It is now understood that lead toxicity is completely preventable. In this regard significant efforts are in place in the developed countries whereas much needs to be done in the developing countries. Spreading the awareness amongst the masses by educating them and reducing the usage of lead following stricter industry norms appears to be the only roadmap to prevent lead poisoning. Efforts being undertaken by the Government of India and other organisations are also mentioned.

GEOSPATIAL ASSESSMENT BASED ON FERTILITY AND MORTALITY DIFFERENTIAL INDICES OF NATURAL SELECTION IN NORTH-WEST AND EASTERN HIMALAYAN POPULATIONS.

There is contradictory evidence of having fewer live births and higher embryonic mortality among high-altitude populations than their counterparts at lower altitude. This study explores the geospatial differences in selection intensities among human populations living in different ecological settings. Reproductive data from post-menopausal women were collected from 75 women from near Shimla, Himachal Pradesh, at an altitude of 2150 m above sea level and 100 women from Jind, Haryana, at an altitude of 227 m. Secondary data were taken from 85 women from the Kinnaur district of Himachal Pradesh at an average altitude of 3420 m. A comparison of the study data was made with similar data from different populations living in the western and eastern Himalayas. The total selection intensity index based on Johnston and Kensinger's index was highest in Shimla and lowest in Kinnaur. The fertility selection component was highest in Shimla and lowest in Kinnaur. The prenatal mortality contribution to the total selection was highest in Shimla (30.76%) and lowest in Kinnaur (2.14%), while the contributions of normalized postnatal mortality were 16.39% and 57.80% in Shimla and Kinnaur, respectively. The fertility component of selection was higher than the mortality component in Shimla, while in the other two places the reverse was observed. Hypoxic conditions at high altitude seem to have little effect on the fertility and embryonic mortality rates of indigenous people. The geospatial differences in the selection intensities may be due to differences in ethnic, behavioural ecology, environmental, cultural and socioeconomic factors.

Dehydroleucodine, a Sesquiterpene Lactone from Gynoxys verrucosa, Demonstrates Cytotoxic Activity against Human Leukemia Cells.

The sesquiterpene lactones dehydroleucodine (1) and leucodine (2) were isolated from Gynoxys verrucosa, a species used in traditional medicine in southern Ecuador. The activity of these compounds was determined against eight acute myeloid leukemia (AML) cell lines and compared with their activity against normal peripheral blood mononuclear cells. Compound 1 showed cytotoxic activity against the tested cell lines, with LD50 values between 5.0 and 18.9 µM. Compound 2 was inactive against all of the tested cell lines, demonstrating that the exocyclic methylene in the lactone ring is required for cytotoxic activity. Importantly, compound 1 induced less toxicity to normal blood cells than to AML cell lines and was active against human AML cell samples from five patients, with an average LD50 of 9.4 µM. Mechanistic assays suggest that compound 1 has a similar mechanism of action to parthenolide (3). Although these compounds have significant structural differences, their lipophilic surface signatures show striking similarities.

Aphid-repellent pheromone E-ß-farnesene is generated in transgenic Arabidopsis thaliana over-expressing farnesyl diphosphate synthase2.

BACKGROUND AND AIMS: Plant-synthesized sesquiterpenes play a pivotal role in chemotactic interactions with insects. Biosynthesis of functionally diverse sesquiterpenes is dependent on the availability of a pool of the precursor farnesyldiphosphate (FDP). In Arabidopsis thaliana, FPS2, encoding cytosolic farnesyldiphosphate synthase, is implicated in the synthesis of cytosolic FDP, but it is not known whether enhanced levels of FDP have a commensurate effect on sesquiterpene-mediated defence responses. This study examined transgenic arabidopsis plants generated to over-express FPS2 in order to determine if any effects could be observed in the response of aphids, Myzus persicae. METHODS: Transgenic arabidopsis plants were generated to over-express FPS2 to produce FPS2 in either the cytosol or the chloroplasts. Morphochemical analyses of the transgenic plants were carried out to detremine growth responses of roots and shoots, and for GC-MS profiling of sesquiterpenes. Aphid response to hyrdo-distillate extracts and head-space volatiles from transgenic plants was assessed using a bioassay. KEY RESULTS: Either over-expression of FPS2 in the cytosol or targetting of its translated product to chlorplasts resulted in stimulatory growth responses of transgenic arabidopsis at early and late developmental stages. GC-MS analysis of hydro-distillate extracts from aerial parts of the plants revealed biosynthesis of several novel sesquiterpenes, including E-ß-farnesene, an alarm pheromone of aphids. Both entrapped volatiles and hydro-distillate extracts of the transgenic leaves triggered agitation in aphids, which was related to both time and dose of exposure. CONCLUSIONS: Over-expression of FPS2 in the cytosol and targeting of its translated product to chloroplasts in arabidopsis led to synthesis of several novel sesquiterpenes, including E-ß-farnesene, and induced alarm responses in M. persicae. The results suggest a potential for engineering aphid-resistant strains of arabidopsis.

PTC bitter taste genetic polymorphism, food choices, physical growth in body height and body fat related traits among adolescent girls from Kangra Valley, Himachal Pradesh (India).

BACKGROUND: Bitter sensitivity among individuals and ethnic groups is partly due to polymorphic bitter taste receptor genes (TAS2Rs). PTC/PROP bitter taste responsiveness at locus TAS2R38 is a well-established index of individual variation in oral sensation that has been linked with predicting food liking and consumption. Previous studies suggest that the relationship between PTC/PROP and anthropometric traits remains controversial. OBJECTIVES: To explore the role of TAS2R38 locus in taste choices, adolescent growth trend for body height, weight and fat patterning among girls and to evaluate their growth status. MATERIALS AND METHODS: Cross-sectional data on 210 girls ranging in age from 11-18 years were collected from Palampur in the Kangra valley of Himachal Pradesh. RESULTS: The proportion of PTC non-tasters was 19.52%. PTC tasters and non-tasters had some differences in their food choices and preferences. More sensitive PTC tasters had a low preference for raw cruciferous vegetables and bitter tasting foods (like bitter gourd) and beverages, while they had higher preference for sweet-tasting foods (p < 0.05). PTC tasters overtook their PTC non-taster counterparts from age 14 through 16 years in having higher mean average skinfold, percentage body fat, fat mass index and fat-free mass index. PTC non-tasters had higher mean stature than tasters through all age groups. PTC tasters had slightly higher mean body weight than tasters at age 11, but in later years the advantage was lost; the total gain among non-tasters through adolescence was higher (78.20%) than tasters (66.92%). PTC thresholds significantly and negatively correlated with body height. CONCLUSIONS: TAS2R38 locus seems to have a role in food tastes, choices and preferences. Perceived bitterness of PTC/PROP thresholds were significantly and negatively correlated with body height and fat-free mass. These results, thus, tentatively suggest that the PTC non-taster gene may help in better absorption of calcium than its counter taster allele. Studies on differences in calcium metabolism between PTC tasters and non-tasters are needed to confirm these indications across cultures.

Effects of Fluoride Toxicity on Female Reproductive System of Mammals: A Meta-Analysis.

Considerable integrative efforts have been made to investigate the effects of fluoride on female reproductive organs since the last years. The ingestion of fluoride causes adverse effects on human health like causing skeletal fluorosis, dental fluorosis, bone fractures, kidney problems, decrease birth rates, weakening of thyroid functionality, and impair intelligence, particularly in children. In this review, we discuss the adverse effects of fluoride on female reproductive organs and presented certain remedies. A total of 53 papers on the effect of fluoride on female reproductive organs, including 6 population surveys were examined. Google Scholar, Google, Research Gate, PubMed, and the International Journal of Fluoride have all been searched for fluoride research papers. Various doses and pathological effects have been described in this review article.

Anticonvulsant activity of ethanol extracts of Vetiveria zizanioides roots in experimental mice.

CONTEXT: Vetiveria zizanioides Linn. (Gramineae), an aromatic plant commonly known as vetiver, is traditionally used for various ailments. Ethanol and aqueous extract of this plant found extensive use in Indian folklore medicine and used in treatment of a wide range of disorders including seizure. However, the anticonvulsant activity of this plant has not been studied. OBJECTIVE: To evaluate anticonvulsant activity of ethanol extract of V. zizanioides (EEVZ) in experimental mice. MATERIALS AND METHODS: Anticonvulsant activity of EEVZ was determined by maximal electroshock stimulation (MES) and pentylenetetrazole (PTZ) in mice for 8 d experimental protocol. The extract at a dose of 100, 200 and 400 mg/kg body weight was administered once by oral route. RESULTS: LD50 value of EEVZ in mice was found at a dose of 600 mg/kg body weight. EEVZ at a dose of 400 mg/kg significantly (p < 0.001) reduced flexion (l5.98 to 3.73 s), extension (13.73 to 0.96 s), clonus (14.07 to 4.93 s), stupor (6.29 to 1.22 s) in the MES model. Further, it increases onset of clonic (88.25 to 708.32 s/30 min) and tonic (139.52 to 1126.39 s/30 min) in the PTZ model. In the PTZ model, 33% normal control and 83% EEVZ (100 mg/kg) animals were alive, while 100% protection was achieved in standard drug phenobarbital (20 mg/kg), EEVZ (200 mg/kg) and EEVZ (400 mg/kg) animals. DISCUSSION AND CONCLUSION: Findings demonstrate that V. zizanioides shows significant anticonvulsant activity in mice.

Real-World Disparities in Remote Follow-Up of Cardiac Implantable Electronic Devices and Impact of the COVID-19 Pandemic: A Single-Center Experience.

Background Remote monitoring (RM) of cardiac implantable electronic devices has been shown to improve cardiovascular morbidity and mortality. To date, no studies have investigated disparities in use and delivery of RM. This study was performed to investigate if racial and socioeconomic disparities are present in cardiac implantable electronic device RM. Methods and Results This was a retrospective observational cohort study at a single tertiary care center in the United States. Patients who received a newly implanted cardiac implantable electronic device or device upgrade between January 2017 and December 2020 were included. Patients were classified as RM positive (RM+) when they underwent at least ≥2 remote interrogations per year during follow-up. Of all eligible patients, 2520 patients were included, and 34% were women. The mean follow-up was 25 months. Mean age was 71±14 years. Pacemakers constituted 66% of implanted devices, whereas 26% were implantable cardioverter-defibrillators, and 8% were cardiac resynchronization therapy with implantable cardioverter-defibrillators. Most patients (83%) were of European American ancestry. During follow-up, 66% of patients were classified as RM+. Patients who were younger, European American, college-educated, lived in a county with higher median household income, and were active on the hospital's patient portals were more frequently RM+. In an adjusted regression model, RM+ remained associated with the use of the online patient portal (odds ratio [OR], 2.889 [95% CI, 2.387-3.497]), presence of an implantable cardioverter-defibrillator (OR, 1.489 [95% CI, 1.207-1.835]), advanced college degree (OR, 1.244 [95% CI, 1.014-1.527]), and lastly with European American ancestry (P<0.05). During the years of the COVID-19 pandemic, the number of RM+ patients increased, whereas the association with ancestry and ethnicity decreased. Conclusions Despite being offered to all patients at implantation, significant disparities were present in cardiovascular implantable electronic device RM in this cohort. Disparities were partly reversed during COVID-19. Further studies are needed to examine health center- and patient-specific factors to overcome these barriers, and to facilitate equal opportunities to participate in RM.

Revisiting the therapeutic potential of gingerols against different pharmacological activities.

The rhizomes of ginger have been in use in many forms of traditional and alternative medicines. Besides being employed as condiment and flavoring agent, it is used in the treatment of nausea, osteoarthritis, muscle pain, menstrual pain, chronic indigestion, Alzheimer's disease, and cancer. Ginger rhizome contains volatile oils, phenolic compounds and resins, and characterization studies showed that [6]-gingerol, [6]-shogaol, and [6]-paradol are reported to be the pharmacologically active components. Gingerol is a major chemical constituent found as volatile oil in the rhizomes of ginger. It has several medicinal benefits and used for the treatment of rheumatoid arthritis, nausea, cancer, and diabetes. Many studies have been carried out in various parts of the world to isolate and standardize gingerol for their use as a complementary medicine. The present review summarizes wide range of research studies on gingerol and its pharmacological roles in various metabolic diseases.

Simultaneous monitoring and dietary risk assessment of 386 pesticides in market samples of black tea.

Black tea samples (390) collected from local markets situated in different locations of India were monitored for the residues of 386 pesticides using QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) based extraction and analysis by gas and liquid chromatography tandem mass spectrometry (GC-MS/MS and LC-MS/MS). Residues of seventeen pesticides were detected, of which propargite, cypermethrin, and novaluron showed the highest % positive detections. A comparison of the concentrations of the detected pesticide residues with the available national and international maximum residue limits (MRLs) showed that seven samples exceeded the Indian MRLs while no sample was found to exceed the CODEX MRLs. The risk due to the detected pesticide levels evaluated in terms of hazard quotient (HQ) and hazard index (HI) was found to be very low (<1), suggesting that the pesticide residues in the tea were safe for consumption by Indian adults and children.

Chemical composition, functional properties and processing of carrot-a review.

Carrot is one of the important root vegetables rich in bioactive compounds like carotenoids and dietary fibers with appreciable levels of several other functional components having significant health-promoting properties. The consumption of carrot and its products is increasing steadily due to its recognition as an important source of natural antioxidants having anticancer activity. Apart from carrot roots being traditionally used in salad and preparation of curries in India, these could commercially be converted into nutritionally rich processed products like juice, concentrate, dried powder, canned, preserve, candy, pickle, and gazrailla. Carrot pomace containing about 50% of ß-carotene could profitably be utilized for the supplementation of products like cake, bread, biscuits and preparation of several types of functional products. The present review highlights the nutritional composition, health promoting phytonutrients, functional properties, products development and by-products utilization of carrot and carrot pomace along with their potential application.

Lumbar Spinal Epidural Capillary Hemangioma: A Case Report and Literature Review.

BACKGROUND Capillary hemangiomas are often seen on the skin of young individuals and are rarely found in the spine. These vascular lesions can arise from any spinal compartment, although they are more commonly found in the intradural extramedullary (IDEM) than the epidural location. We present a unique case of a woman with a histologically proven spinal epidural capillary hemangioma (SECH). The imaging and histopathological characteristics, as well as the treatment strategy of this vascular lesion, are highlighted along with a comprehensive review of the literature. CASE REPORT A 38-year-old woman presented with progressively worsening low back pain that radiated to both legs. Neurological examination revealed a weakness of the left leg without sensory loss. Magnetic resonance imaging (MRI) demonstrated an epidural tumor at L1-L2 level, making an obtuse angle with the cerebrospinal fluid (CSF) on sagittal T2-weighted images. The patient underwent a complete tumor resection without complications or recurrence. The histology revealed a capillary hemangioma. CONCLUSIONS SECH is exceedingly rare, with only 22 cases in the reported literature. Females are more commonly affected than males, and the thoracic spine is more commonly involved than the lumbar spine. SECH often mimics other epidural and IDEM lesions, leading to misdiagnosis. MRI is useful to differentiate SECH from lesions in the various spinal compartments; additionally, MRI is essential for preoperative planning and patient surveillance. Preoperative embolization is an option given the high vascularity of SECH. Surgery is the mainstay treatment, with a good prognosis, in most cases without recurrence.

Pairing medical students on the wards: A multi-site analysis of pairing effect on clerkship performance.

BACKGROUND: Medical students are often paired together on clinical teams during their clerkships. While this practice has multiple potential positive effects, evidence suggests that most students feel that their evaluation is impacted by the other student. This perception negatively impacts the learning environment. We set out to determine whether paired students had a measurable effect on each other's clerkship grade during the medicine sub-internship. METHOD: We examined 186 4th year student-pairs during the required medicine sub-internship at 3 hospital sites of Harvard Medical School from 2013-2017. Chi-square tests were used to determine whether pairing impacted the final clerkship grade. Subsequently we examined whether pairing impacted the sub-internship performance stratified by students' 3rd year core medicine clerkship grade to account for prior performance. FINDINGS: We found no significant deviation between the expected and observed distribution of student grades (chi-square 1.9, p = 0.39) among 186 student pairs, suggesting that pairing had no meaningful effect on the sub-internship grade. We also saw no significant effect of pairing when controlling for prior internal medicine clerkship performance (chi-square 10.9, p = 0.53). CONCLUSIONS: Despite concerns that students on the same medical team may impact each other's performance evaluation, our exploratory study demonstrated no significant effect of student pairing on grades in a medicine sub-internship. Further study of the complex relationship between students on a medical team are warranted to optimize this common practice and enhance the learning environment.