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The distribution of small planet radius ( 0.35) exhibit a lower frequency of sub-Earths (2.5 times less) and sub-Neptunes (1.3 times less) and a higher frequency of super-Earths (1.4 times more) than planets in low-complexity systems. This may suggest that planetary systems with more irregular spacings are more likely to undergo dynamic interactions that influence planet scattering, composition, and atmospheric retention. The gap complexity metric proves to be a valuable tool in linking the orbital configurations of planets to their physical characteristics.

Magnesium Oxide and water are abundant in the interior of planets. Here, the authors predict three new MgO-H2O compounds: Mg2O3H2, MgO3H4 and MgO4H6, and they exhibit superionic behavior in planetary interior conditions.

Objective: Chocolate is a popular food that may affect the activity of the autonomic nervous system (ANS). The aim of this study was to determine the effect of a single dose of dark or milk chocolate on ANS cardiac control during rest and mental stress induced by the Stroop test (ST). Methods: Healthy participants, divided into DARK or MILK chocolate groups, ingested corresponding type of chocolate (1 g/kg body weight). They underwent measurement of ANS during relaxation and ST before and 2 h after chocolate consumption. ANS control was assessed by determination of heart rate (HR) and heart rate variability using parameters related to complex autonomic modulation (TP, SDNN) or primary vagal modulation (HFnu, RMSSD). Results: HR was always increased during ST in both groups. Relaxation HR values after chocolate ingestion were higher only in the DARK chocolate group. During ST, values of TP, SDNN and HFnu decreased before and after chocolate ingestion in the DARK group, but only before chocolate ingestion in the MILK group. RMSSD values decreased during ST before and after chocolate ingestion in both groups. Relaxation TP, RMSSD and HFnu values after chocolate ingestion were lower in the DARK but not in the MILK group. Conclusion: The results suggest that even a single dose of milk chocolate attenuates changes in ANS cardiac control induced by mental stress, whereas a single dose of dark chocolate has an activating effect on the heart via modification of ANS cardiac control at rest. Different levels of sugars and cocoa biologically active compounds in the two types of chocolate could explain the observed effects. [ABSTRACT FROM AUTHOR]

Study Design: Systematic review of the literature and subsequent meta-analysis for the development of a new guideline. Objectives: This manuscript summarizes the recommendations from a new clinical guideline published by the German Spine Society. It covers the current evidence on recommendations regarding the indication, test blocks and use of radiofrequency denervation. The guidelines aim is to improve patient care and efficiency of the procedure. Methods: A multidisciplinary working group formulated recommendations based on the Grades of Recommendations, Assessment, Development, and Evaluation (GRADE) approach and the Appraisal of Guidelines for Research and Evaluation II (AGREE II) instrument. Results: 20 clinical questions were defined for guideline development, with 87.5% consensus achieved by committee members for one recommendation and 100% consensus for all other topics. Specific questions that were addressed included clinical history, examination and imaging, conservative treatment before injections, diagnostic blocks, the injected medications, the cut-off value in pain-reduction for a diagnostic block as well as the number of blocks, image guidance, the cannula trajectories, the lesion size, stimulation, repeat radiofrequency denervation, sedation, cessation or continuation of anticoagulants, the influence of metal hardware, and ways to mitigate complications. Conclusion: Radiofrequency (RF) denervation of the spine and the SI joint may provide benefit to well-selected individuals. The recommendations of this guideline are based on very low to moderate quality of evidence as well as professional consensus. The guideline working groups recommend that research efforts in relation to all aspects of management of facet joint pain and SI joint pain should be intensified. [ABSTRACT FROM AUTHOR]

The characterization of super-Earth- to Neptune-sized exoplanets relies heavily on our understanding of their formation and evolution. In this study, we link a model of planet formation by pebble accretion to the planets' long-term observational properties by calculating the interior evolution, starting from the dissipation of the protoplanetary disk. We investigate the evolution of the interior structure in 5–20 M⊕ planets, accounting for silicate redistribution caused by convective mixing, rainout (condensation and settling), and mass loss. Specifically, we have followed the fate of the hot silicate vapor that remained in the planet's envelope after planet formation as the planet cools. We find that disk dissipation is followed by a rapid contraction of the envelope from the Hill or Bondi radius to about one-tenth of that size within 10 Myr. Subsequent cooling leads to substantial growth of the planetary core through silicate rainout accompanied by inflated radii, in comparison to the standard models of planets that formed with core-envelope structure. We examined the dependence of rainout on the planet's envelope mass, on the distance from its host star, on its silicate mass, and on the atmospheric opacity. We find that the population of planets that formed with polluted envelopes can be roughly divided into three groups based on the mass of their gas envelopes: bare rocky cores that have shed their envelopes, super-Earth planets with a core-envelope structure, and Neptune-like planets with diluted cores that undergo gradual rainout. For polluted planets that formed with envelope masses below 0.4 M⊕, we anticipate that the inflation of the planet's radius caused by rainout will enhance the mass loss by a factor of 2–8 compared to planets with unpolluted envelopes. Our model bridges the gap between the predicted composition gradients in massive planets and the core-envelope structure in smaller planets. [ABSTRACT FROM AUTHOR]

Observations and statistical studies have shown that giant planets are rare around M dwarfs compared with Sun-like stars. The formation mechanism of these extreme systems has remained under debate for decades. With the help of the TESS mission and ground-based follow-up observations, we report the discovery of TOI-4201b, the most massive and densest hot Jupiter around an M dwarf known so far with a radius of 1.22 ± 0.04 R _J and a mass of 2.48 ± 0.09 M _J , about 5 times heavier than most other giant planets around M dwarfs. It also has the highest planet-to-star mass ratio ( q ∼ 4 × 10 ^−3 ) among such systems. The host star is an early M dwarf with a mass of 0.61 ± 0.02 M _⊙ and a radius of 0.63 ± 0.02 R _⊙ . It has significant supersolar iron abundance ([Fe/H] = 0.52 ± 0.08 dex). However, interior structure modeling suggests that its planet TOI-4201b is metal-poor, which challenges the classical core-accretion correlation of stellar−planet metallicity, unless the planet is inflated by additional energy sources. Building on the detection of this planet, we compare the stellar metallicity distribution of four planetary groups: hot/warm Jupiters around G/M dwarfs. We find that hot/warm Jupiters show a similar metallicity dependence around G-type stars. For M-dwarf host stars, the occurrence of hot Jupiters shows a much stronger correlation with iron abundance, while warm Jupiters display a weaker preference, indicating possible different formation histories.

The giant planets were the first to form and hold the key to unveiling the solar system’s formation history in their interiors and atmospheres. Furthermore, the unique conditions present in the interiors of the giant planets make them natural laboratories for exploring different elements under extreme conditions. We are at a unique time to study these planets. The missions Juno to Jupiter and Cassini to Saturn have provided invaluable information to reveal their interiors like never before, including extremely accurate gravity data, atmospheric abundances and magnetic field measurements that revolutionised our knowledge of their interior structures. At the same time, new laboratory experiments and modelling efforts also improved, and statistical analysis of these planets is now possible to explore all the different conditions that shape their interiors. We review the interior structure of Jupiter, Saturn, Uranus and Neptune, including the need for inhomogeneous structures to explain the data, the problems unsolved and the effect that advances in our understanding of their internal structure have on their formation and evolution.

Objectives. The deformability of erythrocytes is their ability to change shape in order to pass through the capillaries. Th is is necessary for quality of microcirculation and sufficient delivery of oxygen to the tissues. Th e aim of our study was to investigate the possible spontaneous changes in the erythrocyte deformability during day and evaluation of the possible direct effects of melatonin (hormone involved in regulation of biorhythms) on the erythrocyte deformability. Methods. Samples of capillary blood were taken from 12 healthy volunteers in the morning (8:00) and early in the evening (16:30). Determination of erythrocyte deformability was done based on the measurement of their filtrability. It was measured immediately aft er the sample collection and 2-hour lasting incubation without or with melatonin (2000 μmol/L). Results. Erythrocyte deformability was significantly lower in the morning (filtrability index: 0.68±0.01 morning vs. 0.71±0.01 early evening, p

Chamomile (Matricaria chamomilla L.) is a widely used medicinal plant possessing several pharmacological effects due to presence of active compounds. In order to study of seed priming effects on seedling growth of chamomile, an experimental design, based on randomized complete design with three replications was conducted under greenhouse conditions in Research Institute of Forests and Rangelands in 2014-2015. Experimental factors were A) three chamomile accessions as code of gene bank 8959 (Brojen), 15123 (Arak) and 23879 (Isfahan), B) five conservation methods including: medium-term storage (active cold room 4 °C for 15 years), long- term storage (basic cold room-18 °C for 15 years), regenerated seeds in open storage 22 °C for 2 years (Control) and aged seed under accelerated ageing )40 °C,98% of relative humidity for 48 and 72h) and C) priming treatments including: without priming /(control), osmopriming (PEG-0.3Mpa), hormonal priming (Gibberllic acid 250 and 500ppm), hydropriming (imbibition with distilled water). Data collected for seed emergence percent, root and shoot length, seedling length, vigor index, seedling weight and three Proxidase, Catalase and Super Oxid Desmotaz (SOD) enzymatic activities. Variance analysis showed significant effects of all factors and their interactions except accession by conservation interaction effects for seedling length (P

To investigate the effect of weed interference on the yield and yield components of rice an experiment was conducted in 2014 at Amol and Mahmoudabad cities in Mazandaran. The experiment was performed in a randomized complete block design with 12 treatments and three replications. Treatments to control weeds were of two types. The first treatment consistsed of controling weeds 10, 20, 30, 40, and 50 days after rice transplanting and then weeds interfered with plant during rest of growing season. A whole season weed control was used as check. The second type treatment at weed interference until 10, 20, 30, 40, and 50 days after rice transplanting and then weeds were controlled during rest of growing season. A whole season interference treatment was used as a weed infested check. The results of variance analysis showed a significant difference for grain yield in either weed free or weed infested treatments between two places. Weed control and interference (except panicle number and biological yield) significantly affected grain yield, grain numbers per panicle and 1000 grain weight. The highest grain yield (3010.83 kg.ha-1) belonged to weed control during whole growing season and lowest grain yield (2075 kg.ha-1) was obtained from weed infested check. Weed infested check resulted in lower grain yield (by 8.31%), panicle number (by 8.33%) and grains number per panicle (by 10.26%) as compared to the control. The critical period of weed control, based on the amount of 5 and 10 percent of yield losses, were fitted by Gompertz and Logestic regression to weed infested weed free treatments, respectively. The results showed that the critical period of weed control in Mahmoudabad region occurred during the days of 22 to 59 and 27 to 36 (from early to end of tillering) based on 10 and 5 percent of yield loss, respectively. The critical point was calculated to be 32 days after transplanting.Thecritical period for Amol region occurred during days of 15 to 54 and 20 to 37 (from early to end of tillering) based on 10 and 5 percent of yield loss, respectively. The critical point was calculated for day 25 after transplanting. In conclusion, the critical period of weed control seems to begin earlier in Amol than in Mahmoudabad and it also had a longer range.

This experiment was conducted in order to evaluate the effect of salinity stress on some traits of two barley genotypes (Hordeum vulgare L.) at greenhouse of Department of Agronomy and Plant Breeding, Shahrekord University, Shahrekord, Iran. A factorial experiment was carried out based on randomized complete block design (RCBD) with three replications. Treatments included two barley genotypes (Afzal (salt-tolerant) and Ligne527 (salt-sensitive)) and five levels of salinity (Control, 100, 200, 300 and 400 mM NaCl). Results showed that salinity left significant effects on leaf RWC, chlorophyll a and b, sodium, potassium, magnesium, calcium and protein concentrations, sodium/potassium ratio and yield components of barley genotypes. Based on the electrophoresis pattern, protein bands were increased by increasing the salinity levels and protein bands with different molecular weight were observed in different salinity levels. It was found that high concentration of potassium ion along with low concentrations of sodium and proline in barley leaf can be used as a criterion for selection and planting this crop in saline conditions. In addition, identification and isolation of the genes encoding salt resistance proteins in barely and transferring of these genes to sensitive genotypes of crop plants can be useful for breeding and generation of tolerant varieties to salinity.

Introduction: A clonal population of B-cells is defined as those cells arising from the mitotic division of a single somatic cell with the same rearrangement of immunoglobulin genes. This gives rise to DNA markers for each individual lymphoid cell and its progenies and enables us to study clonality in different B-cell malignancies using multiplex polymerase chain reaction - PCR. The BIOMED-2 protocol has been implemented for clonality detection in lymphoproliferative diseases and exploits multiplex PCR reaction, subsequently analyzed by heteroduplex analysis (HDA) using polyacrylamide gel electrophoresis (PAGE). With the advent of miniaturization and automation of molecular biology methods, lab-on-chip technologies were developed and replace partially the conventional approaches. We tested device for microfluidic chip, which is used for B-cells clonality analysis, using a PCR reaction for three subregions called frameworks (FR) of the immunoglobulin heavy locus (IGH) gene.

This study was carried out under temperate climate condition of Ilam province, Iran, during 2012-2013 growing season to determine the suitable crop rotation for enhancing nitrogen uptake, utilization, and use efficiency of wheat. A two factor experiment was laid out as split plot arrangement (RCBD) with four replications. The main plots consisted of 6 pre-sowing plant treatments (control, Perko, Buko, Clover, Oilseed radish and combination of three plants Ramtil, Phaselia, Clover), and sub-plots were allocated to four levels of nitrogen fertilizer (Zero, conventionally recommended fertilizer, 50% lower and 50% higher than the recommended fertilizer). Results showed that nitrogen use efficiency (NUE), nitrogen uptake efficiency (NUpE), nitrogen utilization efficiency (NUtE) and nitrogen efficiency ratio (NER) in wheat were significantly affected by crop rotation and nitrogen fertilizer and their interaction. The lowest and highest nitrogen use efficiencies were achieved in oilseed radish-wheat and fallow-wheat rotations. The greatest nitrogen use efficiency in oilseed radish-wheat was due to high utilization efficiency of nitrogen in the rotation. The greatest and smallest nitrogen utilization efficiencies (NUtE) were observed in oilseed radish-wheat and fallow-wheat rotations, respectively. Perko-wheat rotation with application of nitrogen at the conventional level for wheat brings about an acceptable economic yield and high nitrogen uptake and use efficiency and seems to be advantageous to other rotations.

A series of tri- and tetra- substituted imidazoles were synthesized from benzyl, aldehyde and ammonium acetate in the presence of zeolite as an ecofriendly reusable catalyst under microwave irradiation in the absence of solvent. The yields are high to excellent and the use of microwave irradiation reduces reaction times to few minute.

In recent years, increasing application of chemical herbicides has raised concerns over their destructive impacts on living organisms and environmental health and it requires studies on non-chemical weed management methods. As a result, this experiment was initiated in November 2008 at experimental field of Islamic Azad University, Karaj Branch, in order to evaluate weed-suppressive ability of winter rye cover crop and mulch, and its effects on following corn yield production. Treatments included three rye seeding rates (500, 750 and 1000 kernels/m2) and three rye kill dates (29/3/2009, 15/4/2009 and 3/5/2009). In the fall 2008 rye was planted, then in the above three dates have been killed and left on the soil surface to provide mulching effect. Then in middle of June 2009, corn plants planted on the same plots of winter rye. Weeds density and biomass production were monitored in the fourth, sixth and eighth weeks after planting (WAP) corn. Corn yield production was also measured in late October 2009. Results showed that rye seeding rate has not affected weeds significantly but rye kill date had significant effect. The first kill date stimulated weeds germination and growth. The third kill date reduced density of all weeds in the fourth WAP on average 28.73% and their biomass production in the sixth WAP on average 21.38%. This treatment also increased corn grain production 7.89% at the end of the season. Finally, results of the experiment indicate that using cover crops should be combined with other methods to control weeds efficiently and to prevent yield production loss.

This experiment was conducted at the Station of Agricultural Research and Natural Resources, Khoy, Iran in 2007 and 2008 to evaluate the effect of temperature and photoperiod on the duration of development stages of sunflower. A randomized complete block design using a 8 x 3 factorial arrangement with four replications involving eight plantings (29th April, 4th May, 14th May, 24th May, 1st June, 10th June, 19th June and 28th June) and three sunflower cultivars (‘Sor’, ‘Eroflor’, ‘Azargol’). From the results obtained, all development stages, especially the generative phase were influenced by planting date. The duration of each development stage decreased with the delay in planting. The designed models indicated that the minimum temperature and photoperiod were directly proportional to development rate (DR) the whole life cycle of different sunflower cultivars. DR decreased from emergence (E) to physiological maturity (PM) as day length increased. The relationship between DR and photoperiod could be used as a practical model for estimating E to PM duration of these sunflower cultivars.

The giant planets were the first to form and hold the key to unveiling the solar system's formation history in their interiors and atmospheres. Furthermore, the unique conditions present in the interiors of the giant planets make them natural laboratories for exploring different elements under extreme conditions. We are at a unique time to study these planets. The missions Juno to Jupiter and Cassini to Saturn have provided invaluable information to reveal their interiors like never before, including extremely accurate gravity data, atmospheric abundances and magnetic field measurements that revolutionised our knowledge of their interior structures. At the same time, new laboratory experiments and modelling efforts also improved, and statistical analysis of these planets is now possible to explore all the different conditions that shape their interiors. We review the interior structure of Jupiter, Saturn, Uranus and Neptune, including the need for inhomogeneous structures to explain the data, the problems unsolved and the effect that advances in our understanding of their internal structure have on their formation and evolution. [ABSTRACT FROM AUTHOR]

We analyze the dynamics of the forced singularly perturbed differential equations of Duffing’s type with a potential that is bounded from above. We explain the appearance of the large frequency nonlinear oscillations of the solutions. It is shown that the frequency can be controlled by a small parameter at the highest derivative.

With the advent of AR/VR technologies, microdisplay performance requirements are more demanding. Although OLED microdisplays are well suited to satisfy most of these stringent requirements, luminance still needs to be improved. [ABSTRACT FROM AUTHOR]

Ice-rich planets are formed exterior to the water ice line and thus are expected to contain a substantial amount of ice. The high ice content leads to unique conditions in the interior, under which the structure of a planet is affected by ice interaction with other metals. We apply experimental data of ice–rock interaction at high pressure, and calculate detailed thermal evolution for possible interior configurations of ice-rich planets, in the mass range of super-Earth to Neptunes (5–15 M⊕). We model the effect of migration inward on the ice-rich interior by including the influences of stellar flux and envelope mass loss. We find that ice and rock are expected to remain mixed, due to miscibility at high pressure, in substantial parts of the planetary interior for billions of years. We also find that the deep interior of planetary twins that have migrated to different distances from the star are usually similar, if no mass loss occurs. Significant mass loss results in separation of the water from the rock on the surface and emergence of a volatile atmosphere of less than 1% of the planet's mass. The mass of the atmosphere of water/steam is limited by the ice–rock interaction. We conclude that when ice is abundant in planetary interiors the planet structure may differ significantly from the standard layered structure of a water shell on top of a rocky core. Similar structure is expected in both close-in and further-out planets. [ABSTRACT FROM AUTHOR]

Sentinel lymph node biopsy (SLNB) has emerged as an alternative to axillary lymph node dissection during breast cancer surgery during the last 2 decades. However, there are several controversies regarding the indication of the sentinel node biopsy after neoadjuvant chemotherapy which can convert positive lymph nodes to negative. The false-negative rate after neoadjuvant chemotherapy is unacceptably high. This high false-negative rate can be decreased by marking of the positive lymph nodes and removal during sentinel lymph node biopsy procedure in addition to the sentinel lymph nodes. The aim of this study was to investigate the possibility of carbon tattooing of the positive sentinel lymph nodes before neoadjuvant chemotherapy. In 2016, a prospective protocol was launched investigating the black carbon tattooing procedure of the suspective and positive axillary lymph nodes by injecting 0.1-0.5 carbon ink in normal saline under ultrasound guidance. All patients underwent black carbon tattooing of the suspected or positive axillary lymph nodes before the chemotherapy or one week before the primary surgery when chemotherapy was not indicated in the neoadjuvant setting. Sentinel lymph nodes together with lymph nodes marked by the black carbon ink were removed and histologically evaluated. So far 27 patients were treated under this protocol. Breast saving surgery was performed in 22 cases and mastectomy in 5 cases. All patients had invasive ductal carcinoma. In 20 patients neoadjuvant chemotherapy was indicated and in 7 patients primary surgery was performed. All lymph nodes marked by black carbon ink were successfully identified and removed. Sentinel lymph node biopsy was performed in 8 cases and sentinel lymph node biopsy followed by axillary dissection in 15 cases. Axillary dissection alone was performed in 4 cases. In 19 cases, the black carbon ink was present in the sentinel lymph node at the same time and in 4 cases carbon dye was present in other lymph nodes than the lymph node identified during SLNB, which corresponds to 17.4%. In the group of patients undergoing primary surgery, in one case from six, the sentinel lymph node was negative and the lymph node marked with carbon ink positive which represents false-negative lymph node and failure of the SLNB procedure. After neoadjuvant chemotherapy, there was no false-negative lymph node identified, but the conversion of the positive lymph nodes to negative was present in 10 cases (50%). There were no complications attributed to carbon ink tattooing. The results of positive sentinel lymph nodes tattooing have confirmed that this method is safe and allows a decrease in the false negativity rate during the sentinel node biopsy procedure. [ABSTRACT FROM AUTHOR]