The lizard abides: cold hardiness and winter refuges of Liolaemus pictus argentinus in Patagonia, Argentina

In environments where the temperature periodically drops below zero, it is remarkable that some lizards can survive. Behaviorally, lizards can find microsites for overwintering where temperatures do not drop as much as the air temperature. Physiologically, they can alter their biochemical balance to tolerate freezing or avoid it by supercooling. We evaluated the cold hardiness of a population of Liolaemus pictus argentinus Müller and Hellmich, 1939 in the mountains of Esquel (Patagonia, Argentina) during autumn. Additionally, we assessed the thermal quality (in degree-days) of potential refuges in a mid-elevation forest (1100 m above sea level (asl)) and in the high Andean steppe (1400 m asl). We analyzed the role of urea, glucose, total proteins, and albumin as possible cryoprotectants, comparing a group of lizards gradually exposed to temperatures lower than 0 °C with a control group maintained at room temperature. However, we found no evidence to support the presence of freeze tolerance or supercooling mechanisms in this species as related to the analyzed metabolites. Instead, the low frequency of degree-days below 0 °C and temperatures never lower than −3 °C in potential refuges suggest that L. p. argentinus might avoid physiological investments (such as supercooling and freeze tolerance) by behaviorally selecting appropriate refuges to overcome cold environmental temperatures.

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The Role of the Placenta in Perinatal Stroke: A Systematic Review

Journal of Child Neurology ◽

10.1177/0883073820929214 ◽

2020 ◽

Vol 35 (11) ◽

pp. 773-783

Author(s):

Bithi Roy ◽

Susan Arbuckle ◽

Karen Walker ◽

Catherine Morgan ◽

Claire Galea ◽

...

Keyword(s):

Low Frequency ◽

Indirect Evidence ◽

Control Group ◽

Causative Role ◽

Placental Pathology ◽

Inclusion Criteria ◽

Clinical Trial Registration ◽

Perinatal Stroke ◽

Causal Pathway

Context: Placental pathology may be an important missing link in the causal pathway of perinatal stroke. The study aim was to systematically review the literature regarding the role of the placenta in perinatal stroke. MEDLINE, Embase, Scopus, and Web of Science electronic databases were searched from 2000 to 2019. Studies were selected based on predefined criteria. To enable comparisons, placental abnormalities were coded using Redline’s classification. Results: Ten studies met the inclusion criteria. Less than a quarter of stroke cases had placental pathology reported. Placental abnormalities were more common among children with perinatal stroke than in the control group. The most frequent placental abnormality was Redline’s category 2 (thrombo-inflammatory process). Conclusions: Placental abnormalities appear to be associated with perinatal stroke, supporting additional indirect evidence and biological plausibility of a causative role. However, the results should be interpreted cautiously considering the low frequency of placental examination and lack of uniformity in placental pathology reporting. Clinical Trial Registration: PROSPERO Registration no: CRD42017081256.

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Role of metformin pregravid preparation patients with prediabetes impaired glucose toletance

Journal of obstetrics and women s diseases ◽

10.17816/jowd64318-25 ◽

2015 ◽

Vol 64 (3) ◽

pp. 18-25

Author(s):

Evgeniy Konstantinovich Komarov ◽

Tamara Aleksandrovna Pluzhnikova

Keyword(s):

Low Frequency ◽

Free Testosterone ◽

Control Group ◽

Perinatal Complications ◽

Insulin Resistence ◽

Group I ◽

Definition Of ◽

High Level

Tasks of investigation were concluded the characterization of insulin resistence (IR) and hormonal features in patients with prediabetes and influence of diet or metformin on the course of pregnancy and perinatal complications. There were examined 61 womans. The OGTT, definition of insulin levels in plasma and index IR were performed in all patiens. OGTT and index IR were normal in 14 womans (control group I). OGTT was normal but index IR was impared in 33 womans (group IR - II). From this group 22 womans were treated with diet (II A group) and 11 womans treated with metformin (IIB group). OGTT and index IR were abnormal in 14 womans (impared OGTT - III group), they were treated with metformin. Dose of metformin was 1500 mg/d, threatment was continueted for 3-4 manths. Conclusion: Used indexes IR basal and two hour after glucose load were significant in definition of normal and decreased insulin sensitivity (IR). Presence of IR is accompanied by high level of free testosterone in blood without impared secretion of ovarian and suprarenal androgens. There was impared sensitivity of endometrium of secretory stage. The frequency of obstetric and perinatal complications in patients receiving diet not differ from patients treated with metformin. There was only a tendercy to low frequency of threatening miscarriages befor 12 weeks of gestations in paitiens receiving metformin. Development of GDM was observed in 13,1 % of patiens only with presence of IR. The use of metformin in pregravidal stage preserved the development of macrosomia in offsprings of patients with prediabetes.

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Changes and variability of spring-summer air temperature in Czechia during the past 300 years: comparison of instrumental, documentary and natural proxy data

Geografie ◽

10.37040/geografie2017122020190 ◽

2017 ◽

Vol 122 (2) ◽

pp. 190-212 ◽

Cited By ~ 1

Author(s):

Petr Kolář

Keyword(s):

Tree Ring ◽

Air Temperature ◽

Low Frequency ◽

Spatial Distance ◽

Positive Temperature ◽

Harvest Dates ◽

Tree Ring Reconstruction ◽

Instrumental Series ◽

Past 300 Years

Instrumental series, documentary and natural proxy air temperature reconstructions from the area of Czechia were employed to demonstrate spring/summer temporal variability and changes during the 1701–2010 period. Various statistical methods were applied to evaluate cold/warm periods, extreme seasons, oscillations and trends of individual series and also differences between them. Additional reconstructions from the Western and Central Europe were added to examine the role of geographical distance and type of climatological reconstruction. Instrumental series and documentary reconstructions agree well on the occurrence of cold/warm periods and extremes. There is a higher concentration of cold periods during the 18th and particularly 19th centuries. All of the series convincingly represent a positive temperature trend related to anthropogenic global warming. A tree-ring reconstruction contains a larger proportion of low-frequency signal. Despite spatial distance it has been recognized that an affinitive series such as tree-ring analyses from mountainous areas or reconstructions dealing with grape harvest-dates records share a vast extent of mutual variability.

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Low-frequency acoustic measurements on the metallic glass Zr46.8 Ti8.2 Cu7.5 Ni10 Be27.5

10.14293/p2199-8442.1.sop-phys.pwdan0.v1 ◽

2015 ◽

Author(s):

Arnold Seiler ◽

Sebastian Craft ◽

Georg Weiss

Keyword(s):

Metallic Glass ◽

Metallic Glasses ◽

Room Temperature ◽

Low Frequency ◽

Amorphous Solids ◽

Acoustic Measurements ◽

Tunneling Model ◽

Conduction Electrons ◽

Vibrating Reed

The properties of amorphous solids at low temperatures are well known to be dominated by atomic two-level tunneling systems (TS). While the standard tunneling model successfully describes thermodynamic properties of insulating glasses it fails to predict the elastic properties of metallic glasses. To investigate the role of conduction electrons on the density of states and the dynamics of TS vibrating reed experiments are performed. In superconducting glasses the interaction can be switched on and off by means of a magnetic field which suppresses superconductivity and therefore enables electrons to interact with TS. Here we present measurements of the internal friction and the sound velocity of the splat cooled superconducting metallic glass $\text{Zr}_{46.8}\text{Ti}_{8.2}\text{Cu}_{7.5}\text{Ni}_{10}\text{Be}_{27.5}$ measured at frequencies between 600 Hz and 14 kHz and temperatures from 10 mK to room temperature. Within these experiments we used an improved sample geometry to reduce clamping losses and to excite different modes at various frequencies.

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Seasonal Change in Cold Hardiness of Field-grown Ash Trees

HortScience ◽

10.21273/hortsci.31.4.579d ◽

1996 ◽

Vol 31 (4) ◽

pp. 579d-579

Author(s):

Rita L. Hummel ◽

Richard Regan

Keyword(s):

Cold Hardiness ◽

Room Temperature ◽

Tissue Injury ◽

Freeze Tolerance ◽

Fraxinus Pennsylvanica ◽

Willamette Valley ◽

Current Season ◽

Ash Trees ◽

Cold Hardy ◽

Crushed Ice

Cold hardiness of Fraxinus americana `Autumn Purple', Fraxinus oxycarpa `Raywood' and Fraxinus pennsylvanica `Summit' was measured in laboratory tests. Current season stem growth was collected from trees in Willamette Valley nurseries at 3 to 6 week intervals from November 1994 to February 1995 and from October 1995 to March 1996. Replicated 9-cm stem samples with two buds each were placed in tubes and immersed in an ethylene glycol bath. Samples were nucleated with crushed ice, held overnight at –2°C and then frozen at 3°C/hour. After freezing, samples were thawed overnight, incubated at room temperature and 100% relative humidity for 10 to 14 days, then sample viability was determined by visual browning. A Tk50, the temperature at which 50% tissue injury occurred, was calculated for buds and stems. Buds were generally less hardy than stems. `Raywood' was slower to cold acclimate in the fall and did not become as cold hardy in midwinter as `Summit' and `Autumn Purple'. Cold acclimation and midwinter hardiness of `Summit' and `Autumn Purple' was similar; however, `Summit' deacclimated more rapidly. Between the 11 Dec. 1995 and 9 Jan. 1996 freeze tests, `Summit' stems lost about 9 °C of freeze tolerance. In both the 1995 and 1996 February freeze tests, `Summit' stems were less hardy than `Raywood' stems.

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Tryptophan-Niacin Metabolism in Rat with Puromycin Aminonucleoside-Induced Nephrosis

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831.76.1.28 ◽

2006 ◽

Vol 76 (1) ◽

pp. 28-33 ◽

Cited By ~ 7

Author(s):

Yukari Egashira ◽

Shin Nagaki ◽

Hiroo Sanada

Keyword(s):

Body Weight ◽

Urinary Excretion ◽

Enzyme Activities ◽

Treated Group ◽

Control Group ◽

Puromycin Aminonucleoside ◽

Low Level ◽

Key Enzyme

We investigated the change of tryptophan-niacin metabolism in rats with puromycin aminonucleoside PAN-induced nephrosis, the mechanisms responsible for their change of urinary excretion of nicotinamide and its metabolites, and the role of the kidney in tryptophan-niacin conversion. PAN-treated rats were intraperitoneally injected once with a 1.0% (w/v) solution of PAN at a dose of 100 mg/kg body weight. The collection of 24-hour urine was conducted 8 days after PAN injection. Daily urinary excretion of nicotinamide and its metabolites, liver and blood NAD, and key enzyme activities of tryptophan-niacin metabolism were determined. In PAN-treated rats, the sum of urinary excretion of nicotinamide and its metabolites was significantly lower compared with controls. The kidneyα-amino-β-carboxymuconate-ε-semialdehyde decarboxylase (ACMSD) activity in the PAN-treated group was significantly decreased by 50%, compared with the control group. Although kidney ACMSD activity was reduced, the conversion of tryptophan to niacin tended to be lower in the PAN-treated rats. A decrease in urinary excretion of niacin and the conversion of tryptophan to niacin in nephrotic rats may contribute to a low level of blood tryptophan. The role of kidney ACMSD activity may be minimal concerning tryptophan-niacin conversion under this experimental condition.

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The Use of Posterior Pericardiotomy Technique to Prevent Postoperative Pericardial Effusion in Cardiac Surgery

The Heart Surgery Forum ◽

10.1532/hsf98.20111128 ◽

2012 ◽

Vol 15 (2) ◽

pp. 84 ◽

Cited By ~ 4

Author(s):

Canturk Cakalagaoglu ◽

Cengiz Koksal ◽

Ayse Baysal ◽

Gokhan Alici ◽

Birol Ozkan ◽

...

Keyword(s):

Cardiac Surgery ◽

Heart Surgery ◽

Artery Bypass ◽

Pericardial Tamponade ◽

Anxiety Level ◽

Control Group ◽

Echocardiographic Study ◽

Number Of Patients ◽

Hospital Stays

Aim: The goal was to determine the effectiveness of the posterior pericardiotomy technique in preventing the development of early and late pericardial effusions (PEs) and to determine the role of anxiety level for the detection of late pericardial tamponade (PT).Materials and Methods: We divided 100 patients randomly into 2 groups, the posterior pericardiotomy group (n = 50) and the control group (n = 50). All patients undergoing coronary artery bypass grafting surgery (CABG), valvular heart surgery, or combined valvular and CABG surgeries were included. The posterior pericardiotomy technique was performed in the first group of 50 patients. Evaluations completed preoperatively, postoperatively on day 1, before discharge, and on postoperative days 5 and 30 included electrocardiographic study, chest radiography, echocardiographic study, and evaluation of the patient's anxiety level. Postoperative causes of morbidity and durations of intensive care unit and hospital stays were recorded.Results: The 2 groups were not significantly different with respect to demographic and operative data (P > .05). Echocardiography evaluations revealed no significant differences between the groups preoperatively; however, before discharge the control group had a significantly higher number of patients with moderate, large, and very large PEs compared with the pericardiotomy group (P < .01). There were 6 cases of late PT in the control group, whereas there were none in the pericardiotomy group (P < .05). Before discharge and on postoperative day 15, the patients in the pericardiotomy group showed significant improvement in anxiety levels (P = .03 and .004, respectively). No differences in postoperative complications were observed between the 2 groups.Conclusion: Pericardiotomy is a simple, safe, and effective method for reducing the incidence of PE and late PT after cardiac surgery. It also has the potential to provide a better quality of life.

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The Estimation of prostate specific antigen (PSA) concentrations in patients with prostatitis by fully automated ELISA technique.

Journal of Medical Research and Health Sciences ◽

10.15520/jmrhs.v3i11.279 ◽

2020 ◽

Vol 3 (11) ◽

pp. 1100-1104

Author(s):

Hussein Naeem Aldhaheri ◽

Ihsan Edan AlSaimary ◽

Murtadha Mohammed ALMusafer

Keyword(s):

Personal Information ◽

Receptor Gene ◽

Specific Antigen ◽

Gene Clusters ◽

Control Group ◽

P Value ◽

Group Data ◽

Elisa Technique ◽

And Control

The Aim of this study was to determine Immunogenetic expression of Toll-like receptor gene clusters related to prostatitis, to give acknowledge about Role of TLR in prostatitis immunity in men from Basrah and Maysan provinces. A case–control study included 135 confirmed prostatitis patients And 50 persons as a control group. Data about age, marital status, working, infertility, family history and personal information like (Infection, Allergy, Steroid therapy, Residency, Smoking, Alcohol Drinking, Blood group, Body max index (BMI) and the clinical finding for all patients of Prostatitis were collected. This study shows the effect of PSA level in patients with prostatitis and control group, with P-value <0.0001 therefore the study shows a positive significant between elevated PSA levels and Prostatitis.

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Effectiveness Of Toilet Training Education On Mother's Behavior And Toddler Age Toilet Training Ability (18-36 Months)

Jurnal Kesehatan Komunitas ◽

10.25311/keskom.vol5.iss2.288 ◽

2020 ◽

Vol 5 (2) ◽

pp. 49-55

Author(s):

Hafiko Andresni ◽

Zahtamal Zahtamal ◽

Winda Septiani ◽

Mitra Mitra ◽

Lita Lita

Keyword(s):

Sampling Technique ◽

T Test ◽

The Body ◽

Toilet Training ◽

Wilcoxon Test ◽

Control Group ◽

Maternal Knowledge ◽

Control Group Design ◽

Significant Difference

ABSTRACT Toilet training is an effort to train children to be able to control and urinate (BAK) and defecate (BAB). Toilet training is one of the main tasks of children at toddler age. Toilet training is one of the main tasks of children in toddler age which is very important to be done to create independence in children in controlling BAK and BAB and children know the parts of the body and their functions. Data in 2012 shows that ± 60% of parents do not teach toilet training to children from an early age. The aim of the study was to find out the effectiveness of toilet training education on maternal behavior and toilet skills in toddler age training (18-36 months). The study was conducted in July-August 2018. This type of quantitative research used the design of the Quasy pretest and posttest experiment with non-equivalent control group design. Samples were 36 mothers and 36 children with purposive sampling technique. Data analysis used Paired t test, Wilcoxon test, Man-Whitney test an Independent t test. The results showed that toilet training education through lecture methods, modules and maze games was more effective than toilet training education through lecture and leaflet methods on children's knowledge and abilities. Conversely, for the role of mothers in supervision there is no significant difference in effectiveness. Health education is recommended in health promotion programs to increase maternal knowledge, the role of mothers and the ability of toilet training children independently. Keywords: Toilet training, Lecture method, Module, Maze game, Leaflet, Knowledge, Role of mother, Children's ability.

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Clustering-Triggered Efficient Room Temperature Phosphorescence from Nonconventional Luminophores

10.26434/chemrxiv.9959132 ◽

2019 ◽

Author(s):

Shuyuan Zheng ◽

Taiping Hu ◽

Xin Bin ◽

Yunzhong Wang ◽

Yuanping Yi ◽

...

Keyword(s):

Room Temperature ◽

High Efficiency ◽

Spin Orbit Coupling ◽

Design Rationale ◽

Emission Mechanism ◽

Room Temperature Phosphorescence ◽

Electronic Interactions ◽

Energy Gaps ◽

Theoretical Results

Pure organic room temperature phosphorescence (RTP) and luminescence from nonconventional luminophores have gained increasing attention. However, it remains challenging to achieve efficient RTP from unorthodox luminophores, on account of the unsophisticated understanding of the emission mechanism. Here we propose a strategy to realize efficient RTP in nonconventional luminophores through incorporation of lone pairs together with clustering and effective electronic interactions. The former promotes spin-orbit coupling and boost the consequent intersystem crossing, whereas the latter narrows energy gaps and stabilizes the triplets, thus synergistically affording remarkable RTP. Experimental and theoretical results of urea and its derivatives verify the design rationale. Remarkably, RTP from thiourea solids with unprecedentedly high efficiency of up to 24.5% is obtained. Further control experiments testify the crucial role of through-space delocalization on the emission. These results would spur the future fabrication of nonconventional phosphors, and moreover should advance understanding of the underlying emission mechanism.

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