Stars were born in significantly denser regions in the early Universe

The density of the warm ionized gas in high-redshift galaxies is known to be higher than what is typical in local galaxies on similar scales. At the same time, the mean global properties of the high- and low-redshift galaxies are quite different. Here, we present a detailed differential analysis of the ionization parameters of 14 star-forming galaxies at redshift 2.6-3.4, compiled from the literature. For each of those high-redshift galaxies, we construct a comparison sample of low-redshift galaxies closely matched in specific star formation rate (sSFR) and stellar mass, thus ensuring that their global physical conditions are similar to the high-redshift galaxy. We find that the median log [OIII] 5007/ [OII] 3727 line ratio of the high-redshift galaxies is 0.5 dex higher than their local counterparts. We construct a new calibration between the [OIII] 5007/ [OII] 3727 emission line ratio and ionization parameter to estimate the difference between the ionization parameters in the high and low-redshift samples. Using this, we show that the typical density of the warm ionized gas in star-forming regions decreases by a median factor of $7.1^{+10.2}_{-5.4}$ from z ~ 3.3 to z ~ 0 at fixed mass and sSFR. We show that metallicity differences cannot explain the observed density differences. Because the high- and low-redshift samples are comparable in size, we infer that the relationship between star formation rate density and gas density must have been significantly less efficient at z ~2-3 than what is observed in nearby galaxies with similar levels of star formation activity.Comment: 16 pages, 6 figures, accepted for publication in Ap

Genetic Analyses Of Calcium Circuits In Arabidopsis Vegetative And Reproductive Development

Calcium homeostasis is maintained by the action of different calcium transporters including channels, antiporters, and calcium pumps. Calcium channels provide an influx pathway whereas calcium antiporters and pumps provide an efflux system. Together, influx and efflux systems create a calcium circuit. One of the calcium circuits operating in plant cells is associated with the endoplasmic reticulum (ER). In chapter II, results are presented on the functional characterization of three calcium pumps in Arabidopsis with ER and ER-like localization. In chapter III and IV, Arabidopsis pollen transcriptome data are presented, which compare heat-stress induced changes in the pollen transcriptomes of wild type and a mutant harboring a knockout of a cyclic nucleotide gated channel (cngc16).Calcium pumps ACA1, 2, and 7 belong to the type IIB subfamily of Ca2+-ATPases. In a comparison of protein sequences for all ten ACA Ca2+-pumps in Arabidopsis, ACA1, 2, and 7 cluster as a distinct subgroup. Members of this subgroup all appeared to localize to the ER or ER-like structures when expressed in stably transformed plants with a YFP tag and imaged with confocal microscopy. A loss-of-function for all three ACAs, ACA1, 2, and 7, resulted in plants showing a lesion-like phenotype in the leaves. This phenotype was suppressed by the expression of a NahG transgene, which encodes an enzyme that degrades salicylic acid, indicating that the lesion phenotype is dependent on salicylic acid. In addition, a triple knockout of aca1/2/7 resulted in a decrease in pollen transmission efficiency when assayed in competition with wild type pollen. This pollen transmission deficiency was exacerbated when crosses were done under temperature stress conditions. Both phenotypes could be rescued by the expression of any of the threeACA1, 2 or 7 genes, suggesting that all three genes encode Ca2+-pumps that are functionally interchangeable. Together, these results establish ACA1, 2, and 7 as a subgroup of ER-localized autoinhibited Ca2+-ATPases that normally function to suppress an SA-dependent programmed cell death pathway in leaves, and are also important for pollen fitness under normal and temperature stress conditions.Under temperature stress conditions, pollen harboring a cngc16 knockout are nearly sterile, and show a greater than 10-fold decrease in pollen transmission efficiency compared to wild-type pollen. To gain further insight into mechanisms underlying this hypersensitivity, an RNA-Seq experiment was performed to compare the stress-dependent changes in the pollen transcriptomes from wild-type and a cngc16 knockout parent. In response to a heat stress, the wild-type pollen transcriptome showed 2,612 changes (≥2-fold changes and adjusted p<0.01). Of these, 641 changes (~ 25%) failed to occur in the cngc16 knockout, identifying a subset of failed responses that might contribute to the poor stress tolerance displayed by cngc16 pollen. At the same time, the mutant displayed 2,733 changes that were not seen in wild-type pollen. Of these differences between wild type and cngc16, 148 were associated with transcription factors, suggesting that a primary defect in the cngc16 mutant lies in its inability to properly reprogram the transcriptome in response to a heat stress. Overall, the RNA-Seq experiment here provides a great resource for research community to explore genes function of potential importance to pollen thermotolerance

The Cost Analysis of Patients with Traffic Traumatic Injuries Presenting to Emergency Department; a Cross-sectional Study

Introduction: Road traffic traumatic injuries are the leading cause of death especially among young men who are mostly vulnerable victims. This catastrophe is more complicated in low to middle income countries.&nbsp;Objective: This study assessed the financial costs of traffic casualties in Iran.&nbsp;Method: One thousand trauma patients presenting to the emergency department of Shohaday-e-Tajrish Hospital were included in the study. The prehospital and hospital costs as well as the expenses of physiotherapy, rehabilitation, outpatient visits and further surgical interventions were considered as direct expenses. The costs of productivity loss were estimated as indirect expenses.&nbsp;Results: The direct and indirect costs were assessed 27.4% and 72.6% of total, respectively. The mean age of permanent disability was 43 years old. The average expenses of temporary and permanent disabilities were 2934.4 million rials (nearly 4.2 million rials per patient) and 23.9 billion rials (1.1 billion rials per person), respectively.&nbsp;Conclusion: The national burden of traffic injuries in Iran is significantly destructive as it consists of 2.19 % of Gross Domestic Product annually. Besides, young men are involved in most of the traffic accidents representing the need to establish rigorous preventive instructions and reduce human, and financial costs

The Cost Analysis of Patients with Traffic Traumatic Injuries Presenting to Emergency Department; a Cross-sectional Study

Introduction: Road traffic traumatic injuries are the leading cause of death especially among young men who are mostly vulnerable victims. This catastrophe is more complicated in low to middle income countries.&nbsp;Objective: This study assessed the financial costs of traffic casualties in Iran.&nbsp;Method: One thousand trauma patients presenting to the emergency department of Shohaday-e-Tajrish Hospital were included in the study. The prehospital and hospital costs as well as the expenses of physiotherapy, rehabilitation, outpatient visits and further surgical interventions were considered as direct expenses. The costs of productivity loss were estimated as indirect expenses.&nbsp;Results: The direct and indirect costs were assessed 27.4% and 72.6% of total, respectively. The mean age of permanent disability was 43 years old. The average expenses of temporary and permanent disabilities were 2934.4 million rials (nearly 4.2 million rials per patient) and 23.9 billion rials (1.1 billion rials per person), respectively.&nbsp;Conclusion: The national burden of traffic injuries in Iran is significantly destructive as it consists of 2.19 % of Gross Domestic Product annually. Besides, young men are involved in most of the traffic accidents representing the need to establish rigorous preventive instructions and reduce human, and financial costs

Investigating the Emotional Theory of Mind in Iranian Married Women: A Descriptive Phenomenological Study

In marital relationships, the type of perception of the spouse’s behavior affects how the social information and behavior of the other couple is processed, leading to psychological consequences. Thus, a higher perception of each other’s mental state is followed by sincerity and more satisfaction with the relations. The present study was performed by using a descriptive phenomenological qualitative approach with the aim of investigating emotional theory of mind in 19 married Iranian women who were selected by purposive sampling in 2017. In order to coding data, MAXQDA 2018 software and the Colaizzi’s method were used for coding and analyzing the data, respectively. Finally, about three concepts including the emotion type, emotion expression and emotion regulation were extracted from the interviews. Results showed in emotion type, women remarked positive emotions of satisfaction and gratitude and negative emotions of sorrow and sadness only about themselves. Although emotion expression was possible through three ways but in women\u27s view point, men did not react to positive emotion non-verbally. In the third category, coping with negative emotions in the form of going into retreat was raised merely about men and emotion discharge and forgetfulness merely about women. The findings of the present study, a qualitative examination of emotions of the two genders from the viewpoint of women, is to a great extent in line with previous self-report and quantitative studies; they can be applied for Iran and other countries with similar culture and structure

Biological Response to Carbon-Family Nanomaterials: Interactions at the Nano-Bio Interface

During the last few decades, several studies have suggested that carbon-based nanomaterials, owing to their unique properties, could act as promising candidates in biomedical engineering application. Wide-ranging research efforts have investigated the cellular and molecular responses to carbon-based nanomaterials at the nano-bio interfaces. In addition, a number of surface functionalization strategies have been introduced to improve their safety profile in the biological environment. The present review discusses the general principles of immunological responses to nanomaterials. Then, it explains essential physico-chemical properties of carbon-familynanomaterials, including carbon nanotubes (CNTs), graphene, fullerene, carbon quantum dots (CDs), diamond-like carbon (DLC), and mesoporous carbon biomaterials (MCNs), which significantly affect the immunological cellular and molecular responses at the nano-bio interface. The discussions also briefly highlight the recent studies that critically investigated the cellular and molecular responses to various carbon-based nanomaterials. It is expected that the most recent perspective strategies for improving the biological responses to carbon-based nanomaterials can revolutionize their functions in emerging biological applications

The impact of endogenous estrogen exposure duration on fracture incidence : a longitudinal cohort study

Author's accepted version (postprint).This is an Accepted Manuscript of an article published by Oxford University Press in Journal of Clinical Endocrinology and Metabolism on 04/05/2022.Available online: https://academic.oup.com/jcem/advance-article-abstract/doi/10.1210/clinem/dgac248/6580306?redirectedFrom=fulltextacceptedVersio