Reflection of electromagnetic waves from mixtures of plane gravitational and scalar waves

We consider colliding wave packets consisting of hybrid mixtures of electromagnetic, gravitational and scalar waves. Irrespective of the scalar field, the electromagnetic wave still reflects from the gravitational wave. Some reflection processes are given for different choice of packets in which the Coulomb-like component $\Psi_2$ vanishes. Exact solution for multiple reflection of an electromagnetic wave from successive impulsive gravitational waves is obtained in a closed form. It is shown that a succesive sign flip in the Maxwell spinor arises as a result of encountering with an impulsive train (i.e. the Dirac's comb curvature) of gravitational waves. Such an observable effect may be helpful in the detection of gravitational wave bursts.Comment: 20 pages, 3 ps figures, small typos corrected, published versio

Efektivitas Penggunaan Modul Berbasis Lingkungan terhadap Hasil Belajar Peserta Didik Kelas VII SMP Negeri 28 Bulukumba

Penelitian ini bertujuan untuk mengetahui gambaran hasil belajar peserta didik Kelas VII A SMP Negeri 28 Bulukumba setelah diajar menggunakan modul berbasis lingkungan dan untuk mengetahui seberapa besar keefektifan penggunaan modul berbasis lingkungan terhadap hasil belajar peserta didik kelas VII A SMP Negeri 28 Bulukumba. Populasi dalam penelitian ini adalah seluruh peserta didik kelas VII SMP Negeri 28 Bulukumba tahun ajaran 2015/2016 yang terdiri dari 3 kelas dengan jumlah peserta didik 77, sampel sebanyak 24 sampel yang bertempat di kelas VII A. Instrumen penelitian yang digunakan dalam penelitian yaitu instrumen respon peserta didik terhadap modul dan instrumen tes hasil belajar. Skala yang digunakan untuk respon peserta didik terhadap modul yaitu skala Likert. Teknik analisis data yang digunakan yaitu analisis data statistik deskriptif dan inferensial. Hasil belajar peserta didik dengan modul fisika berbasis kontekstual mencapai nilai rata-rata 81,25. Rata-rata hasil belajar peserta didik termasuk kategori tinggi melebihi standar KKM yakni 70. Berdasarkan hasil uji hipotesis dengan menggunakan uji-t diperoleh nilai thitung > ttabel maka H0 ditolak sehingga Ha diterima. Dengan demikian dapat disimpulkan bahwa modul berbasis lingkungan efektif digunakan karena nilai hasil belajar peserta didik sebanyak 75% mencapai standar KKM

Investigation of the Effect of Pipeline Size on the Cross Flow Injection Process

Injection pumps constitute an essential component for many industrial applications. The main focus of this study is to predict the effect of the size of the pipeline on the cross flow injection process. A test-rig was designed, built and equipped with three different pipelines, 1½", ¾" and ½" diameters. Comparison was made under constant line pressure of 40-bar and line flow rate of 5 liter/min, with a fixed injection pump rotational speed of 100 rpm. The main parameter tested was the injection dose capacity at different pump displacements. Cross flow mixing process is also theoretically studied using 3D-CFD analysis to show the injection cross flow behavior for the same geometry and parameters used for experimental test. Results show that increasing the size of the pipeline increases injection pump doses ability. This effect is insignificant at lower injection pump displacements, while the effect of the size of the pipeline becomes dominant when increasing the displacement. By changing the size of the pipeline from ½" to 1½" diameter injection pump dose capacity increases by 3.24% at 100% pump displacement. Selecting larger pipe sizes for injection ports is recommended whenever possible

Wave propagation over a beach within a nonlinear theory

Wave propagation over a beach is considered within a nonlinear theory in shallow water. Lagrangian coordinates are used to describe the problem. The solution is expanded in double series involving a small parameter and local oscillations. Two cases are treated: The beach with appreciable inclination on the horizontal (cliff) and the beach of small inclination. We show that finite solutions are obtained, in contrast to the linear theory which involves a logarithmic singularity at the shoreline. For the cliff, it is shown that local oscillations do not appear in the first two orders of approximation, and the incident wave is totally reflected without loss of energy at this order of approximation. The case of an incident wave on the beach is considered. The deformation of this wave is investigated and explicit formulae are obtained for the reflected wave and for the local oscillations, to shed light on the energy transfer due to interaction with the beach

Subsequent Fertility of Goats with Prenatal Mortality Diagnosed by Ultrasound and Treated by PGF 2 α

Thirteen Saanen and Saanen crossbred female goats, between the ages of 6 months and 7, years were presented to the clinic, College of Veterinary Medicine, Sudan University of Science and Technology, for sonographic pregnancy diagnosis. Transabdominal ultrasound was performed using 3.5 MHz probe which revealed non-viable fetuses as judged by absence of heart beats and movements. Twelve goats were given single i/m injection of PGF2α analogue and 5% oxytetracycline. Ten goats responded to the treatment and six of them became pregnant and gave birth within the normal gestational period. One goat was diagnosed as non-pregnant, one goat developed hydrometra, and the subsequent fertility of two goats was unknown. Two full-term goats did not respond to treatment. Another dose of PGF2α was administered to them and again they did not respond. Manual attempts were done to deliver the full-term goat with dilated cervix and they were unsuccessful. Cesarean section and hysterectomy were then performed for the three full-term goats with unfavorable outcome. It can be concluded that ultrasound is a rapid, reliable, and nonhazardous procedure for the diagnosis of fetal mortality in goats and PGF2α treatment in conjunction with oxytetracycline is an efficient treatment

Protective effect of propolis on manganese chloride neurotoxicity of olfactory bulb in adult male albino rat

Background: Manganese (Mn) is widely used for industrial purposes and exposure to high levels of Mn may cause an irreversible brain disease. Propolis is a natural plant product; it acts as a powerful reactive oxygen species scavenger and improves the neurodegeneration process. Materials and methods: In this study 40 adult male albino rats were divided randomly into four groups 10 rats each: group I (control group), group II manganese chloride (MnCl2) received 10 mg/kg/day/orally for 4 weeks by intra-gastric tube, group III (propolis group) received 50 mg/kg/day/orally for 4 weeks by intra-gastric tube, and group IV (MnCl2 + propolis group) received the same doses with the same duration and route as in groups II and III. Rats were sacrificed after 24 h of last dose. The olfactory bulbs removed, the right bulb cut to be processed for haematoxylin and eosin, immunohistochemical staining and the left cut for electron microscopic studies. Results: Results revealed that rat olfactory bulb from MnCl2 group showed darkly stained mitral cells with dark pyknotic nuclei, some show pericellular spaces and vacuolation, dark apoptotic cells in granular cells, neuropil vacuolation and pyknotic astrocyte. Electron microscopic examination showed abnormal granular cell with irregular damaged nuclear membrane, rupture of myelin fibre. Mitral nerve cell with destructed nucleus, many cytoplasmic vacuoles, swollen rough endoplasmic reticulum, vacuolated mitochondria and neuropil were observed. Manganese chloride + propolis group showed improvement compared to MnCl2 group. Conclusions: It was concluded that propolis can ameliorate the toxic changes of manganese chloride on rat olfactory bulb

Red Blood Cell Transfusion Independence Following the Initiation of Iron Chelation Therapy in Myelodysplastic Syndrome

Iron chelation therapy is often used to treat iron overload in patients requiring transfusion of red blood cells (RBC). A 76-year-old man with MDS type refractory cytopenia with multilineage dysplasia, intermediate-1 IPSS risk, was referred when he became transfusion dependent. He declined infusional chelation but subsequently accepted oral therapy. Following the initiation of chelation, RBC transfusion requirement ceased and he remained transfusion independent over 40 months later. Over the same time course, ferritin levels decreased but did not normalize. There have been eighteen other MDS patients reported showing improvement in hemoglobin level with iron chelation; nine became transfusion independent, nine had decreased transfusion requirements, and some showed improved trilineage myelopoiesis. The clinical features of these patients are summarized and possible mechanisms for such an effect of iron chelation on cytopenias are discussed

Role of Nigella sativa seed oil on corneal injury induced by formaldehyde in adult male albino rats

Formaldehyde is frequently used in occupational environments, its toxicity concerns to all who work closely with it such as anatomists. Nigella sativa is an amazing herb with a rich historical and religious background; its seeds are the source of its active ingredients. The purpose of the present study was to evaluate the role of Nigella sativa oil on corneal injury induced by formaldehyde in adult male albino rats. Forty adult male albino rats were divided randomly to four groups 10 rats each: I — Control group, II — Formaldehyde exposed group, III — Nigella sativa oil group (40 mg/kg/day) via intragastric tube daily for 2 weeks and IV — Formaldehyde and Nigella sativa group. Rats were sacrificed with ether, the corneas were extracted, one processed for haematoxylin and eosin stain and the other was used for transmission electron microscopic examination. Our results in group II revealed marked disorganisation, erosion, vacuolation and necrosis of epithelial cells with loss of parts of epithelial layer. Large congested invasion of blood vessels with separation and disorganisation of stromal fibrils. The corneas of group IV showed intact layers of epithelial cells with appearance close to control group. Star shaped cells (limbal stem cells) were obviously noticed in basal and intermediate layer with intact Bowman’s membrane. Stroma showed regular parallel collagen, limbal stem cells were also noticed in group III. We concluded that Nigella sativa oil can ameliorate the toxic changes of formaldehyde on rat corneas.