bluuebunny/crossref_metadata_2025_split huggingface dataset:
Extracellular Fluid Volume Changes in Carcinus Maenas during Acclimation to Low and High Environmental Salinities
Authors: Harris R. R. , Andrews M. B. 
Published: April 2021

ABSTRACT
Changes in extracellular fluid (ECF) volume of Carcinus maenas (L.) were studied in vivo during acclimation to low and high environmental salinities. Initial investigations showed that there was a rapid equilibration into this compartment of the ECF markers used ([3H]inulin and [14C] hydroxymethyl inulin). Earlier reports of a relatively slow marker distribution, indicated from clearance curves, can be explained by high clearance rates occurring when frequent blood sampling was carried out. After transfer of the crabs to media hyposmotic to the haemolymph, ECF volumes decreased transiently to 74·8% of the initial volume, but within 40 h in 26% sea water original volumes were restored. Calculation of intracellular water contents suggests that a volume limitation phase precedes the regulatory return to the original volume. In hyperosmotic media, the ECF volumes increased significantly (to a maximum of 143 %) but, in contrast to the response in hyposmotic conditions, showed only a partial return to the original volumes.
The neuromuscular basis of swimming movements in embryos of the amphibian Xenopus Laevis
Authors: Kahn J. A. , Roberts A. , Kashin S. M. 
Published: April 2021

ABSTRACT
When removed from their egg membranes, Xenopus embryos can swim. High-speed cinematography shows that, in swimming, lateral undulations pass rostro-caudally down the body. The swimming rhythm period is 40-100 ms. In swimming, electrical activity in myotomal muscles alternates on opposite sides of a segment and sweeps rostro-caudally in ipsilateral myotomes.
Myotome muscle physiology was examined. Muscle fibres are electrically coupled to each other, and the fibres are able to spike. The possible role of a myotomal conduction pathway in swimming is discussed.
Regulation of Blood Oxygen Affinity in the Australian Blackfish Gadopsis Marmoratus
Authors: Dobson G. P. , Baldwin J. 
Published: April 2021

ABSTRACT
The effects of thermal acclimation on whole blood oxygen affinity were examined in the freshwater blackfish Gadopsis marmoratus. Oxygen equilibrium curves for 20 °C-acclimated fish were shifted to the right of curves obtained for 10 °C-acclimated fish when determined at both 20 °C and 10 °C. Oxygen equilibrium curves obtained for solutions of stripped haemoglobin prepared from blood of 20 °C- and 10 °C-acclimated fish did not show the differences observed for whole blood. Thermal acclimation did not alter the number, migration rates, or relative amounts of the five electrophoretic forms of haemoglobin present in blackfish blood. The intraerythrocytic concentration of nucleoside triphosphates was higher in the 20 °C-acclimated fish than in 10 °C-acclimated fish, while the whole blood haemoglobin concentration was lower in the 20 °C-acclimated fish. These differences gave NTP : Hb4 molar ratios of 1·68 for the 20 °C-acclimated fish and 1·32 for 10 °C-acclimated fish. The effects of nucleoside triphosphates on oxygen affinity were similar for stripped haemoglobins of both acclimation groups. The change in NTP:Hb4 molar ratios with acclimation temperature acts to enhance oxygen unloading to the tissues rather than oxygen uptake at the gills at the higher acclimation temperature. As the waters inhabited by the blackfish retain high oxygen tensions at 20 °C, these changes in blood oxygen affinity could be considered adaptive if they were associated with elevated rates of oxygen-dependent metabolism at the higher temperatures.
Blood Gas Transport in the Cephalopod, Sepia Officinalis
Authors: Johansen Kjell , Brix O. L. E. , Lykkeboe Gunnar 
Published: April 2021

ABSTRACT
Blood gas transport was studied in unrestrained free-swimming cuttlefish, Sepia officinalis, following cannulations of an efferent branchial (arterial) vessel and the vena cava cephalica with indwelling catheters.
In well-aerated water the arterial averaged about 100·00 mmHg and was fully saturated with O2. Mixed venous varied between 17 and 40 mmHg, typically corresponding to blood O2 utilizations of 80% or higher. Some blood samples showed venous pH to exceed arterial, a tendency becoming more distinct during exposure to hypoxic water. The resulting higher O2 affinity of venous compared to arterial blood discourages O2 unloading in the tissues, while promoting efficient O2 loading in the gills. A high n-value of Sepia blood (n = 4·7) is important for maintaining a large arteriovenous O2 content difference and a high utilization of circulating O2.
Hydrophilic Cuticle - The Basis for Water Vapour Absorption by the Desert Burrowing Cockroach,Arenivaga Investigata
Authors: O’Donnell M. J. 
Published: April 2021

ABSTRACTA micro-method has been developed for measuring the water content of materials over a range of humidities. A vapour pressure osmometer measures the equilibrium humidity in a sealed chamber containing the sample and an accurately known volume of water. The cuticle of the hypopharyngeal bladders, which are the sites for atmospheric water absorption in Arenivaga, has a water affinity much greater than that of unspecialized cuticle from this and other species. This difference is also found in washed samples. The hydrophilic properties of the bladder cuticle are therefore not due to dissolved salts in the frontal body fluid which is applied to the bladders during absorption in vivo. Dissolved salts reduce cuticle water affinity. The basis for this effect is discussed with reference to known properties of polyelectrolytes. A model of in vivo absorption is proposed. It is suggested that the cyclical addition of frontal body fluid alters the water affinity of bladder cuticle so that condensed water is released. Some of the water is then swallowed.
Responses to Hypersaline Exposure in the Euryhaline CrayfishPacifastacus Leniusculus
Authors: G. Wheatly Michèle , McMahon B. R. 
Published: April 2021

ABSTRACTThe effect of 48 h of hypersaline exposure (25, 50 and 75% SW) on haemocyanin oxygenation properties in the euryhaline crayfish Pacifastacus leniusculus was investigated in vitro and in vivo. In vitro significant increases in affinity and cooperativity were measured, although the magnitude of the Bohr shift was unaffected. In vitro dialysis of haemolymph against physiological salines of variable ionic composition proved that these changes were only partly attributable to altered levels of haemolymph ions, implicating the existence of modulators other than H+ and inorganic ions, the possible identities of which are discussed. Significant depressions of both pre- and postbranchial oxygen tensions ( and ) were observed, but O2 delivery was maintained by utilization of the venous reserve and by an increase in haemocyanin O2 affinity. This occurred despite a concomitant acidosis whose effect on O2 affinity was directly opposed by the ‘salt’ effect. Under hypersaline conditions, haemocyanin played an increasingly important role in O2 delivery in vivo. Despite a reduction in the concentration of combined O2 at complete saturation of the pigment (), indicating lowered haemocyanin concentration, compensatory changes in O2-binding and cardiac output precluded an impairment to O2 transfer. Equilibration at the tissues () in FW was less effective than at the gills () but progressively improved with hypersaline exposure reversing this trend. Although effects of increased salinity on O2 equilibrium characteristics were qualitatively similar in vivo and in vitro, some interesting quantitative differences are discussed.
Intracellular and extracellular acid-base regulation in the tropical fresh-water teleost fishSynbranchus marmoratusin response to the transition from water breathing to air breathing
Authors: Heisler Norbert 
Published: April 2021

ABSTRACTIn the tropical fresh water fish, Synbranchus marmoratus, transition from water breathing to air breathing, induced by reduction of oxygen partial pressure () in the environmental water below 16 mmHg, causes a considerable rise in the arterial partial pressure of carbon dioxide () from 5·6 to 26 mmHg on the average (half time of the rise between 2 and 6·5 h). The associated fall in arterial plasma pH by about 0·6 units is not compensated by an increase in plasma bicarbonate concentration, whereas the intracellular pH of white skeletal muscle and heart muscle is kept almost constant by elevation of the intracellular bicarbonate concentration. The additional bicarbonate is generated by intracellular non-bicarbonate buffering, and by net transfer into the intracellular space of bicarbonate formed by buffering in blood. Only a relatively small quantity of bicarbonate is taken up from environmental water.This type of acid-base regulation, with almost complete intracellular pH compensation and only minor bicarbonate uptake (equivalent H+ release or OH− uptake) from water, is attributed to several factors. Probably the most important of these is the lack of continuous contact of the gills, which are the main site of ion transfer processes, with the environmental water during air breathing. Regardless of the mechanisms involved, this particular strategy of acid-base regulation provides a constant milieu for the intracellular structures and demonstrates the prevalence of intracellular over extracellular acid-base regulation.
A retrospective study of open and endoscopic nephron sparing surgery in the treatment of complex renal tumors
Authors: Li Ting-ting , Feng Jia , Li Yan-ling , Sun Qian 
Published: April 2021

Objective: To investigate clinical outcomes of open and retroperitoneal laparoscopic nephron-sparing surgery in the treatment of complex renal tumours.
Methods: A retrospective case study was conducted. Patients with complex renal tumours admitted to our hospital between January 2018 and September 2019 were enrolled; the included patients (n=40) were divided into the observation group (open partial nephrectomy, n=20) and control group (laparoscopic partial nephrectomy, n=20) according to operation modes. The operation time, renal warm ischaemia time, intraoperative blood loss, renal pedicle blocking time, intestinal function recovery time, postoperative hospital stay, and postoperative complications were recorded.
Results: Significant differences were noted regarding renal warm ischaemia time, renal pedicle blocking time, intraoperative blood loss, operation time, and postoperative hospital stay between the observation and control groups (P<0.05); however, no significant difference was observed in intestinal function recovery time and postoperative drainage days (P>0.05).
Conclusion: Open surgery remains the recommended surgical method for the treatment of few complex tumours in the renal hilus region and has gradually become the renal surgery of choice at present, although laparoscopic surgery has evolved tremendously.
doi: https://doi.org/10.12669/pjms.37.4.3457
How to cite this:Li TT, Feng J, Li YL, Sun Q. A retrospective study of open and endoscopic nephron sparing surgery in the treatment of complex renal tumors. Pak J Med Sci. 2021;37(4):1031-1035. doi: https://doi.org/10.12669/pjms.37.4.3457
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Team-based learning versus Traditional lecture-based learning: An investigation of students’ perceptions and academic achievements
Authors: Nawabi Shazia , Bilal Rabia , Javed Muhammad Qasim 
Published: April 2021

Objectives: Evaluation of TBL from students’ perspective has been done extensively, but limited studies have analyzed the effect of TBL on students’ academic performance. Objectives of the present study were to assess students’ perceptions about team-based learning versus traditional lectures and then to compare with students’ grades in both TBL and lecture-based assessments.
Methods: Cross-sectional descriptive study which included 147 dentistry students was conducted between March and June, 2020 at Qassim University, Saudi Arabia. A self-composed 10 item closed ended instrument was administered through electronic mail. One block from each academic year was selected randomly and organizers were requested to provide grades of students in both TBL and lecture-based exams. Grades from A to F were determined as achievement indicator and were compared statistically using Kruskal Wallis, Tuckey Posthoc and Chi-square tests.
Results: A total of 120 students (81.6%) responded to the survey, and mean perception score was (3.29±0.94). Perceptions of students, regarding TBL as a learning strategy were comparatively superior as compared to the lectures. Students scored significantly higher grades in TBL exams (p<0.05) as compared to lecture-based assessments. Gender-wise analysis indicated that female students secured significantly higher grades in the TBL.
Conclusion: We conclude that dentistry students perceived TBL as superior teaching and learning strategy compared to traditional lectures. Their perception was verified by their significant higher academic achievements in the assessments for the coursework taught by utilizing team-based learning strategy.
doi: https://doi.org/10.12669/pjms.37.4.4000
How to cite this:Nawabi S, Bilal R, Javed MQ. Team-based learning versus Traditional lecture-based learning: An investigation of students’ perceptions and academic achievements. Pak J Med Sci. 2021;37(4):1080-1085. doi: https://doi.org/10.12669/pjms.37.4.4000
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
The relationship between problematic cell phone use, eating disorders and social anxiety among university students
Authors: Gokce Ayse , Ozer Ali 
Published: April 2021

Objective: Problematic cell phone use is common among young age groups which include university students, and may be accompanied by social anxiety and eating disorders. We aimed to examine the relationship between problematic cell phone use, social anxiety and eating disorders among university students.
Methods: The universe of this cross-sectional study consists of 28,669 students receiving education at a Inonu University between October 2017 - November 2017. With a confidence interval of 95% and power of 80%, the sample size was calculated to be 308. The survey forms used in the study included students’ sociodemographic characteristics, data regarding cell phone usage, Problematic Mobile Phone Use Scale, Liebowitz Social Anxiety Scale and Eating Attitudes Test. The statistical analyses were conducted using Student t, One Way ANOVA, Spearman Correlation Test and Binomial Logistic Regression Analysis.
Results: The students in the study group demonstrated a 46.1% rate of problematic cell phone use. The students’ Problematic Mobile Phone Use Scale total scores showed a significant correlation with smoking, and daily duration and purpose of cell phone use (p<0.05).
Conclusion: University students demonstrate high rates of problematic cell phone use; in addition, individuals who use cell phones for increased hours or for certain purposes display higher total scores on the Problematic Mobile Phone Use Scale. Students should be educated on limiting problematic cell phone use.
doi: https://doi.org/10.12669/pjms.37.4.4124
How to cite this:Gokce A, Ozer A. The relationship between problematic cell phone use, eating disorders and social anxiety among university students. Pak J Med Sci. 2021;37(4):1201-1205. doi: https://doi.org/10.12669/pjms.37.4.4124
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Routledge Handbook on Arab Media, Noureddine Miladi and Noha Mellor (eds) (2021)
Authors: Hägglund Helena 
Published: April 2021

Review of: Routledge Handbook on Arab Media, Noureddine Miladi and Noha Mellor (eds) (2021)
London: Routledge, 528 pp.,
ISBN 978-0-42942-708-4, e-book, ISBN 978-1-13838-548-1, h/bk, £190
The Role of the Social Media in Empowering Saudi Women’s Expression, Hend T. Alsudairy (2020)
Authors: Derham Reem Ali Al 
Published: April 2021

Review of: The Role of the Social Media in Empowering Saudi Women’s Expression, Hend T. Alsudairy (2020)
Newcastle upon Tyne: Cambridge Scholar Publishing, 121 pp.,
ISBN 978-1-5275-4974-6, 358.30 QAR
Stochastic methods defeat regular RSA exponentiation algorithms with combined blinding methods
Authors: Dugardin Margaux , Schindler Werner , Guilley Sylvain 
Published: April 2021

Abstract
Extra-reductions occurring in Montgomery multiplications disclose side-channel information which can be exploited even in stringent contexts. In this article, we derive stochastic attacks to defeat Rivest-Shamir-Adleman (RSA) with Montgomery ladder regular exponentiation coupled with base blinding. Namely, we leverage on precharacterized multivariate probability mass functions of extra-reductions between pairs of (multiplication, square) in one iteration of the RSA algorithm and that of the next one(s) to build a maximum likelihood distinguisher. The efficiency of our attack (in terms of required traces) is more than double compared to the state-of-the-art. In addition to this result, we also apply our method to the case of regular exponentiation, base blinding, and modulus blinding. Quite surprisingly, modulus blinding does not make our attack impossible, and so even for large sizes of the modulus randomizing element. At the cost of larger sample sizes our attacks tolerate noisy measurements. Fortunately, effective countermeasures exist.
Sensitivities and block sensitivities of elementary symmetric Boolean functions
Authors: Zhang Jing , Li Yuan , Adeyeye John O. 
Published: April 2021

AbstractBoolean functions have important applications in molecular regulatory networks, engineering, cryptography, information technology, and computer science. Symmetric Boolean functions have received a lot of attention in several decades. Sensitivity and block sensitivity are important complexity measures of Boolean functions. In this paper, we study the sensitivity of elementary symmetric Boolean functions and obtain many explicit formulas. We also obtain a formula for the block sensitivity of symmetric Boolean functions and discuss its applications in elementary symmetric Boolean functions.
Nephrogenic Diabetes Insipidus
Authors: ALBERTAZZI ELENA , ZANCHETTA DEBORAH , BARBIER PASCALINE , FARANDA SARA , FRATTINI ANNALISA , VEZZONI PAOLO , PROCACCIO MIRELLA , BETTINELLI ALBERTO , GUZZI FRANCESCA , PARENTI MARCO , CHINI BICE 
Published: April 2021

Abstract.
The aim of this study was to identify loss-of-function mutations of the V2 vasopressin receptor gene (AVPR2) in Italian patients affected by X-linked nephrogenic diabetes insipidus (NDI). Mutations were found in 15 of the 18 unrelated families investigated: nine of these mutations were previously unknown, including two affecting residues located in regions known to be important for determining the pharmacologic properties of the receptor, which were therefore functionally investigated. The first (A84D) involves a residue located near an aspartic acid (D85) that is highly conserved in all G protein-coupled receptors and that is believed to play a role in the process of their isomerization into functionally active and inactive states. The present study indicates that this mutation not only affects receptor folding in such a way as to lead to its retention inside the intracellular compartments but, as expected, also has profound effects on its binding and coupling properties. The second was a mutation of a tryptophan located at the beginning of the first extracellular loop (W99R) that greatly impaired the binding properties of the receptor and had a minor effect on its intracellular routing. Molecular analysis of the first extracellular loop bearing this mutation suggests that this residue plays a fundamental role in stabilizing the peptide/receptor interactions responsible for the high-affinity binding of agonists to the V2 receptor.
Angiopoietin-2 Is a Site-Specific Factor in Differentiation of Mouse Renal Vasculature
Authors: YUAN HAI TAO , SURI CHITRA , LANDON DAVID N. , YANCOPOULOS GEORGE D. , WOOLF ADRIAN S. 
Published: April 2021

Abstract.
Angiopoietin-1 (Ang-1) stimulates endothelial and vascular network differentiation through the Tie-2 receptor tyrosine kinase, while Ang-2 modulates this activation in embryo and tumor growth. The nephrogenic pattern of Ang-2 was documented in a mouse strain that expresses the LacZ reporter gene driven by the Ang-2 promoter. Heterozygous animals were healthy with morphologically normal kidneys, and they were examined after X-gal staining. At embryonic days 10.5 (E10.5) and E12.0, transgene expression was absent in the mesonephros and metanephros. At E14.0, expression was noted in the metanephric artery and its major branches. At E19.0 and in neonatal kidneys, expression was maintained in larger renal artery branches, extending to arcuate and smaller cortical vessels. Histologically, transgene expression was located in multiple layers of vessel wall cells, extending further from the endothelium than α-smooth muscle actin. The mesangium of immature glomeruli also expressed LacZ. In the first 3 postnatal weeks, a new pattern became evident, with intense X-gal staining in the inner stripe of the outer medulla, where a subset of thin descending limbs of loops of Henle expressed the transgene. This dynamic and developmentally regulated pattern indicates that Ang-2 is an early marker of the renal pericyte and vascular smooth muscle lineage and is also an epithelial-derived growth factor. Because Tie-2 is widely expressed by differentiating renal endothelia, this study is consistent with the hypothesis that Ang-2 has roles in kidney vascular maturation.
Course of Renal Injury in the Mpv17-Deficient Transgenic Mouse
Authors: O'BRYAN THOMAS , WEIHER HANS , RENNKE HELMUT G. , KREN STEFAN , HOSTETTER THOMAS H. 
Published: April 2021

Abstract.
The mutant Mpv17 mouse is a transgenic strain that fails to express a protein that is normally expressed in the kidney and that is associated with peroxisomes. The present studies provide a quantitative examination of renal function and structure in this strain compared to its control CFW strain. By 52 wk of age, the mutant strain developed proteinuria (urinary protein to creatinine ratio: 25 ± 14 versus 3 ± 1, mutant versus control), albuminuria (urinary albumin to creatinine ratio: 23 ± 15 versus 0.1 ± 0.1, mutant versus control), and hypoalbuminemia (2.1 ± 0.4 versus 2.5 ± 0.2 G/dl, mutant versus control), but without arterial hypertension or major reduction in filtration (serum creatinine 0.14 ± 0.04 versus 0.18 ± 0.12 mg/dl, mutant versus control). The Mpv17 glomeruli were enlarged (0.98 ± 0.12 versus 0.52 ± 0.02 μm3 × 106, mutant versus control). Glomerular sclerosis became widespread (95 ± 3 versus 23 ± 32%, mutant versus control) and was preceded by mesangiolysis and microaneurysms. Tubulointerstitial disease was conspicuous by its absence. The intrarenal vasculature was normal in the mutant mice. Electron microscopy demonstrated focal foot process fusion and mesangiolysis. Thus, this mutant strain of mouse develops proteinuria and a distinct glomerulopathy including mesangiolysis but little interstitial injury all due to the loss of expression of a single gene.