375 research outputs found
Simulating contrail formation within cirrus in the high-resolution ICON-LEM model
Cirrus clouds are common in the upper troposphere and contribute to the earth's radiation budget. The radiative forcing caused by cirrus is dependent on their macro-, microphysical and optical properties; therefore, a change in the cirrus properties leads to a change in their radiative impacts. Recently a study showed evidence of changes in cirrus optical depth due to contrail ice formation within cirrus in satellite remote sensing data. So far, no detailed studies are available that can quantify the impact of contrail ice formation within cirrus on cirrus microphysical and optical properties. Therefore, the aim of the presented work is to improve our understanding of contrail formation within cirrus and their impact on cirrus cloudiness.
A high-resolution ICON-LEM (ICOsahedral Non-hydrostatic- Large-Eddy Modelling) in weather forecasting mode at a horizontal resolution of 625 meters is used. In order to study contrail formation within cirrus, a parameterization for contrail formation within cirrus, consisting of contrail ice nucleation and ice crystal loss in the vortex phase, is implemented and modified to include the impact of pre-existing cirrus on contrail ice formation. Two very different synoptic situations and associated cirrus cloud fields are sampled to cover a large range of cirrus properties, which represent a very thin cirrus connected with a high-pressure system and an average thick in-situ formed and liquid origin cirrus connected with a frontal system. The sublimation of cirrus ice crystals in the engine and sublimation of/ deposition on the cirrus ice crystals mixed in the exhaust plume causes a change in the plume’s water vapor mixing ratio. This change is mostly positive and contributes maximally 20% of the water vapor emitted from aircraft due to the combustion of conventional fuels. This change in the plume’s water vapor mixing ratio leads to a change in the contrail formation threshold temperature and contrail ice nucleation while ice crystal survival within the vortex phase appears to be nearly unchanged. In areas where the cirrus ice water content is large, the change in the contrail formation threshold temperature reaches values of up to 2K, and associated changes in the nucleation rate of contrail ice crystals lead to changes in ice crystal number concentrations of maximally 107 m-3, the similar order of magnitude that would result from disregarding the impact of cirrus ice crystals. Even though cirrus ice crystals sublimate within the descending vortices and may act to increase relative humidity leading to a decrease in contrail ice sublimation, the preceding growth phase, in which cirrus ice crystals can grow faster, often even at the expense of contrail ice crystals, leads to smaller contrail ice crystals. Both effects together compensate, leaving ice crystal survival rates approximately unchanged.
The formation of contrail ice crystals within cirrus introduces large perturbations in ice crystal numbers, increasing ice number concentrations by 2 to 4 orders of magnitude. The ice water content in the cirrus also changes, but the changes are smaller than for ice crystal number concentrations. Perturbations can be long-lived, with changes discernible even after 6 hours. During their lifetime, perturbations spread and affect large parts of the cirrus clouds at flight level and below. Contrail ice formation can accelerate the dissolution of cirrus due to the replacement of a few large cirrus ice crystals by many small contrail ice crystals. The change in the cirrus properties causes a change in the optical depth of the cirrus. Maximum increase and decrease in cirrus optical depth reach values of 4 in thick cirrus. However, probability of decrease in optical depth is significantly lower than the probability of increase in optical depth due to contrail formation within cirrus. The simulations show clear signs of adjustments of cloud properties of cirrus downwind of cirrus that was directly modified by contrail formation. The ice water content, ice number concentrations, and optical depth of those cirrus further downwind appear to be decreased, which needs to be considered when estimating the climate impact of contrail formation within cirrus in the future.Zirruswolken treten häufig in der oberen Troposphäre auf und tragen zur Energiebilanz der Erde bei. Der Strahlungsantrieb von Zirren hängt von deren makrophysikalischen, mikrophysikalischen und optischen Eigenschaften ab. Deshalb führt eine Änderung der Zirruswolkeneigenschaften zu einer Änderung ihrer Strahlungswirkung. Eine kürzlich erschienene Studie analysierte Satellitenfernerkundungsdaten und lieferte den Hinweis, dass Kondensstreifeneisbildung in Zirren deren optische Dicke beeinflusst. Bis jetzt existieren keine detaillierten Studien, die den Einfluss von Kondensstreifeneisbildung in Zirren auf deren mikrophysikalische und optische Eigenschaften quantifizieren. Daher ist es das Ziel dieser Arbeit, das Verständnis zu Kondensstreifeneisbildung in Zirren und zum Einfluss von Kondensstreifen auf die Zirrusbewölkung zu verbessern.
Das hochauflösende Modell ICON-LEM (ICOsahedral Non-hydrostatic- Large-Eddy Modelling) wird verwendet und im Wetterprognose-Modus mit einer horizontalen Auflösung von 625 Metern betrieben. Um Kondensstreifenbildung in Zirren zu untersuchen wird eine Parametrisierung für Kondensstreifenbildung in Zirren implementiert, welche Kondensstreifeneisbildung und den Eiskristallverlust in der Vortex-Phase beschreibt. Diese Parametrisierung wird modifiziert, um den Einfluss präexistierender Zirruswolken auf die Kondensstreifeneisbildung einzubeziehen. Zwei sehr unterschiedliche synoptische Situationen und entsprechende Zirruswolkenfelder werden beprobt, um eine große Spannweite verschiedener Zirruseigenschaften abzudecken. Zum einen eine sehr dünne Zirruswolke verbunden mit einem Hochdruckgebiet, zum anderen eine in-situ und konvektiv geformte Zirruswolke mittlerer Dicke verbunden mit einem Frontsystem. Die Sublimation von Zirruseiskristallen im Flugzeugtriebwerk und die Sublimation von / Deposition auf die Zirruseiskristalle gemischt in der Abgasfahne bewirkt eine Änderung des Wasserdampfmischungsverhältnisses in der Abgasfahne. Diese Änderung ist meist positiv und trägt zu maximal 20% des vom Flugzeug durch Verbrennung konventioneller Treibstoffe emittierten Wasserdampfes bei. Diese Änderung des Wasserdampfmischungsverhältnisses der Abgasfahne führt zu einer Änderung des Temperaturschwellwertes der Bildung von Kondensstreifen und der Kondensstreifeneisbildung, während das Überleben der Eiskristalle in der Vortexphase weitgehend unverändert bleibt. In Gebieten mit hohem Zirruseiswassergehalt reicht diese Änderung der Temperaturschwelle der Kondensstreifenbildung bis zu 2K. Damit verbundene Änderungen der Nukleationsrate von Zirruseiskristallen führen zu Änderungen der Eiskristallanzahlkonzentration von maximal 107 m-3. Diese Größenordnung ist vergleichbar mit dem Effekt einer Vernachlässigung des Einflusses von Zirruseiskristallen. Obwohl Zirruseiskristalle in den absinkenden Vortices sublimieren und damit die relative Feuchte erhöhen, was eine verringerte Sublimation des Zirruseises bewirkt, führt das schnellere Anwachsen der Eiskristalle in der vorangegangenen Wachstumsphase, oft auf Kosten der Zirruseiskristallbildung, zu kleineren Eiskristallen in Kondensstreifenzirren. Diese beiden Effekte kompensieren sich gegenseitig, so dass die Überlebensrate der Eiskristalle kaum verändert wird.
Die Bildung von Kondensstreifeneiskristallen in Zirruswolken bewirkt eine beträchtliche Störung der Kristallzahlen, was zu einer Erhöhung der Eiskristallanzahlkonzentration von zwei bis vier Größenordnungen führt. Der Eiswassergehalt in der Zirruswolke verändert sich ebenfalls, jedoch sind diese Änderungen geringer als im Fall der Eiskristallanzahlkonzentrationen. Diese Störungen können langlebig sein, so dass Änderungen auch nach sechs Stunden sichtbar sind. Während der Lebensdauer der Störungen verteilen diese sich und beeinflussen große Teile der Zirruswolken in Flughöhe und darunter. Kondensstreifeneisbildung kann die Auflösung von Zirren beschleunigen, da statt weniger großer Zirruseiskristalle, eine große Zahl kleiner Kondensstreifeneiskristalle entstehen. Die Veränderung der Zirruseigenschaften bewirkt eine Änderung der optischen Dicker der Zirren. Maximalwerte für Zu- und Abnahme der optischen Dicker der Zirren betragen bis zu 4 in dichten Zirruswolken. Jedoch ist die Wahrscheinlichkeit einer Abnahme der optischen Dicker durch Kondensstreifenbildung in Zirren deutlich geringer als die Wahrscheinlichkeit einer Zunahme. Die Simulationen zeigen deutliche Anzeichen für Anpassungen der Wolkeneigenschaften von Zirren in Windrichtung von Zirruswolken, die direkt durch Kondensstreifenbildung modifiziert wurden. Der Eiswassergehalt, die Eiskristallanzahlkonzentrationen und die optische Dicke jener in Windrichtung gelegener Zirren scheinen verringert zu sein. Dieser Effekt sollte in Zukunft bei der Abschätzung des Klimaeffektes der Kondensstreifenbildung in Zirren berücksichtigt werden
Prenatal risk score in high risk pregnancy cases and perinatal outcome: a study from South India
Background: Identification of a high risk pregnancy by Coopland score helps the obstetrician to identify patient at high risk and also elaborate a prognosis of pregnancy. The present study was conducted to evaluate perinatal outcomes in high and low risk pregnancies.Methods: In the present study of 100 cases of high risk caesarean section were evaluated and compared with 100 cases of low risk caesarean sections over a period of two years.Results: 40% and 28% of the high risk and low risk group respectively had low birth weight baby. In the high risk group, 2% had neonatal death, while these figures were 0% in the control group respectively. 28% babies in the study group and 18% babies in the control group had mild to severe depression and Apgar score below 6-4. 42% and 12% babies in the high risk and low risk group respectively had perinatal morbidity which was in the form of prematurity, IUGR, respiratory distress syndrome and birth asphyxia. 7% and 4% cases in both study and control group respectively had poor perinatal outcome.Conclusions: We suggest Coopland risk scoring for every case admitted for a caesarean section, which will be definitely helpful in predicting and evaluating the eventual perinatal outcomes. Appropriate timely care and referral can have a positive impact in lowering the perinatal mortality and morbidity and possibly better maternal outcome
A MACHINE LEARNING LINEAR REGRESSION MODEL TO PREDICT FUTURE GIANT PANDA POPULATION
Increasingly used as the insignia of China, the zaftig and enchanting Giant Panda lives on mountains of southwest China. The Giant Panda is on the WWF logo and is known as “National Treasure” in China. In this study, we predict the future Giant Panda population by using machine learning algorithms of the simple linear regression model. We take different variables to predict the next 30 years of the Giant Panda population. Focusing on the factors which affect the Giant Panda population. We take several parameters for this research like Bamboo Population, Annual Rainfall in China, Carbon Stock in Bamboo Stems, Deforestation, and Human Influence and Population of Giant Panda. Despite their peak status and relative deficiency of natural predators, pandas are still at risk and multiple intimidations from human influence have left just over 1,800 Pandas in the forest. To be ready for future troubles it is mandatory to have a pre-look of some conditions so that we can be prepared for that. Substantially, Endangered species at the edge of extinction are kept in extra special conservation. The machine learning algorithms developed with a wide-ranging of training datasets that help to find results faster and accurately
Role of trans vaginal sonography with hysteroscopy in detection of uterine causes of abortions
Background: Recurrent pregnancy loss (RPL) is one of the most frustrating and difficult areas in reproductive medicine because the aetiology is often unknown and there are only few evidence-based diagnostic and treatment strategies. Objective of this study was to compare the role of trans vaginal sonography with hysteroscopy in detection of uterine causes of abortions.Methods: This prospective cohort study was conducted in the department of obstetrics and gynaecology, Kasturba Hospital, Daryaganj, Delhi. The study was conducted from January 2016 to December 2016.Results: On transvaginal sonography majority of women i.e. 39(78%) patients had normal ultra-sonographic findings. 11(22%) showed various abnormal findings. Most commonly diagnosed abnormal finding on TVS was polyp, seen in 5(10%) patients. It was seen as a well-defined, uniformly hyperechoic mass within the endometrial cavity. normal hysteroscopic findings were seen in 27(54%) patients. Rest 23(46%) patients had abnormal uterine factors as diagnosed by hysteroscopy.Synechiae was detected in 9(18%) patients. It was the most common abnormality detected on hysteroscopy. Out of 9 patients who had synechiae, 2 had severe dense adhesions. In 6 patients, the adhesions were mild and flimsy. While minimal adhesions were noted in 1 patient, seen near the cornua.Conclusions: hysteroscopy is still the gold standard for diagnosis and most definitive procedure of choice if any kind of operative intervention is required
An analytic Study of the Key Factors Influencing the Design and Routing Techniques of a Wireless Sensor Network
A wireless sensor network contains various nodes having certain sensing, processing & communication capabilities. Actually they are multifunctional battery operated nodes called motes. These motes are small in size & battery constrained. They are operated by a power source. A wireless sensor network consists of a huge number of tiny sensor nodes which are deployed either randomly or according to some predefined distribution. The sensors nodes in a sensor network are cooperative among themselves having self-organizing ability. This ensures that a wireless network serves a wide variety of applications. Few of them are weather monitoring, health, security & military etc. As their applications are wide, this requires that sensors in a sensor network must play their role very efficiently. But, as discussed above, the sensor nodes have energy limitation. This limitation leads failure of nodes after certain round of communication. So, a sensor network suffers with sensors having energy limitations. Beside this, sensor nodes in a sensor network must fulfill connectivity & coverage requirements. In this paper, we have discussed various issues affecting the design of a wireless sensor network. This provides the readers various research issues in designing a wireless sensor network
To study analyze maternal serum alpha-fetoprotein as a biomarker of placental adherence in low lying placenta
Background: To study the place of Maternal Serum Alfa Feto Protein (MSAFP) as a biomarker of placental adherence in low lying placenta, and to study maternal outcome in the study group.Methods: This is a prospective observational study analyzing the conditions and the data of 90 cases with low lying placenta in a tertiary care hospital. The analysis was done for the association of MSAFP with MRI, perinatal and maternal outcome.Results: The level of MSAFP was found higher in 14 out of 15 cases (93.3%) of placenta previa with placental adherence. There was significant surgical intervention (80%) and increased maternal morbidity (68.8%) in the study group with placental adherence and raised MSAFP respectively.Conclusions: MSAFP is an important biomarker for prognostication of placental adherence in low lying placenta
A prospective study of adverse drug reactions associated with chemotherapy in patients of carcinoma head and neck in Government Cancer Hospital Indore, India
Background: Adverse drug reactions (ADRs) has become one of the major health issues due to wide use of medications worldwide. Chemotherapy is one of the treatment lines in which multiple drugs are commonly used for long term in cancer patients, are more prone to cause ADR.Methods: Head and neck cancer patients admitted in government cancer hospital, Indore for chemotherapy were included in study for a period of 6 month from March to August 2019. Data from chemotherapy related ADR was obtained either from patient’s case reports or interview of patients, recorded in suspected adverse drug reaction reporting form (version 1.3) of CDSCO and analyzed.Results: During 6 months duration total 126 patients (M:F=108:18) were enrolled in the study, among which 251 ADRs were reported. Majority of ADRs occur in 45-60 years of age group followed by 30-45 years. Paclitaxel, cisplatin, 5-florouracil (5-FU) combinations (45.2%) implicated highest number of ADRs followed by paclitaxel and carboplatin combination (38%). Most common ADR was alopecia and constipation. ADR related mostly with GIT system followed by integumentary, haematological system while CNS was least affected.Conclusions: In this study Ca tongue was most commonly seen head and neck cancer followed by Ca buccal mucosa. Age group 45-60 years were commonly affected. Paclitaxel, cisplatin, 5-FU combination was commonly used regimen and primary cause of ADR. Alopecia and constipation were noted to be most common ADR. Other ADRs reported were mild and easily manageable
A prospective randomised controlled study on the effects of myoinositol on ovarian functions and metabolic factors in women with polycystic ovarian syndrome
Background: Polycystic ovary syndrome is one of the most common endocrine disorder affecting five to ten percent women of reproductive age group. Myoinositol has been reported to be helpful in PCOS women with deranged metabolic and ovarian factors. In this study, we have evaluated the effects of myoinositol in women with PCOS.Methods: A total of 132 patients are included in the study. 66 patients in the study group were given myoinositol 4 gm daily for three months, while other 66 patients in the control group were given folic acid for the same duration. The parameters were evaluated at the beginning, six and twelve weeks after intervention.Results: After completion of 12 weeks, myoinositol was found to have a significant effect on reduction of BMI of the patients. No changes was seen in the fasting insulin levels, but a significant decrease in fasting blood sugar levels of patients was seen. Also, a significant increase in serum HDL was seen in the study group. Luteal phase serum progesterone was also increased in the study group.Conclusions: Myoinositol has got noticeable effects in reducing the BMI of PCOS women. We didn’t find any significant effect of the drug over the fasting insulin level. Serum HDL was increased in some patients. An increase in luteal phase progesterone was noticed which suggest that myoinositol may be beneficial in ovulation. However further studies are needed to establish the same
An Investigation paper on Congestion Control Policy
In the advancement of network technology traffic affects performance factors like file synchronization, communication throughput and overall all the scenario where one are having continues connectivity of business to the rectifying organizations, all the business functionality are going for the achievement of paperless communication infrastructure where one are deploying all his working by the internet technology such high speed network communication infrastructure always required well suited congestion less architecture scheme to achieve quality of services ,In the field of different communication area there are many applications has be running at present for all type of users likesenior, junior and all business users categories. Network proposed many protocols and algorithm for the improvement in flow of the network,Ethernet project 802 and protocols series 802.11a/b/c/d/e has been working at network layer in which user’s found some times network work well with priorities choice of network connection but sometimesstruggles with the same.To analyze the actual report of congestion policies here author of the paper are presenting analytical study so that one can understand the lack of functionality in communication with specific network implementations
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