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Graphical abstract, Highlights • The oral toxicity effect of crude methanolic extract (CMX) of Diospyros mespiliformis hochst ex a. Dc (ebenaceae) was studied. • Crude methanolic extract of D. mespiliformis has an LD50 higher than 5 g/kg post oral treatment in rats, thus relatively safe. • The leaf and bark ethyl acetate fractions of D. mespiliformis were relatively safe post 28-days repeated treatment in rats., Diospyros mespiliformis, commonly called Jackal berry or African ebony, belongs to the plant family, Ebenaceae. The roots, barks and leaves have been used traditionally to treat wide varieties of conditions, however, there is limited information and literature reports concerning the toxicity and safety of this plant. The present study was conducted to evaluate the acute and sub-chronic toxicity of the crude methanolic extract of Diospyros mespiliformis and its fraction in Wistar rats. Diospyros mespiliformis was extracted by methanol 96 %. The crude methanolic extract was then fractionated into low, average and high polar compounds using hexane, ethyl acetate and butanol respectively. For the acute toxicity study, the revised limit Dose Test of “Up and Down” procedure according to the OECD guideline was used to determine the median lethal dose (LD50) of the crude methanolic leaf and bark extracts using a single fixed dose (5 g/kg) of the extracts administered by oral-gavage sequentially to 5 female Wistar rats. The rats were observed for instant death and toxicity signs for 24 h and then daily for 14 days. In the sub-chronic toxicity study, the bark and leaf ethyl acetate fractions (extract) was administered orally at doses of 250, 500 and 750 mg/kg bw /day respectively for 28 days to healthy Wistar rats. At the end of the experimental period, body weight, certain haematological, serum biochemical and histopathological parameters were evaluated. Results showed that acute oral administration of crude methanolic extract of Diospyros mespiliformis (5 g/kg bw) produced neither mortality nor visible changes in behavior or any other physiological activities and indicated that the LD50 of crude methanolic leaf and bark extract was greater than 5 g/kg bw in Wistar Rats. In the 28-days repeated dose oral toxicity study, no significant toxic effects was detected in any of the parameters evaluated. In conclusion, the crude methanolic extract was found safe in the acute toxicity study and the ethyl acetate fraction of Diospyros mespiliformis in the sub chronic study in rats could be safe for therapeutic purposes over a period not exceeding 28 days.

Objectives To analyse the clinical and histopathological features of oral leukoplakia (OL) in the Sudan, and to identify the risk factors associated with dysplastic and malignant changes. Methods Records of 117 cases with the diagnosis of OL at the Department of Oral Pathology in the period from 2010 to 2017 were reviewed. Results Of the 117 cases included in this study, 30 cases (25.6%) showed carcinoma in the initial diagnostic biopsy. The mean age at diagnosis was 59.8 years with a male/female ratio of 3.3:1. The lip (48.7%) and the gingiva (31.6%) were the predominantly affected sites. Multivariate regression analysis revealed that females were associated with 3.36-fold [95% confidence interval (CI), 1.36-10.76; P = 0.012] higher risk of malignant transformation compared with males. Verrucous leukoplakia was associated with 3.38-fold (95% CI, 1.12-10.19; P = 0.031) higher risk of malignant transformation compared with homogeneous leukoplakia. Exclusive Toombak dipping was the significant risk factor for the presence of dysplasia in OL (odds ratio, 9.35; 95% CI, 1.28-67.99; P = 0.027). Conclusions Clinical and histopathological features of OL were analysed and correlated. Toombak dipping was the significant risk factor for dysplastic changes, while female gender and verrucous leukoplakia were the factors associated with malignant transformation.

Heart failure (HF) is a complex clinical syndrome with symptoms and signs that result from any structural or functional impairment of ventricular filling or ejection of blood. Limited data is available regarding the in-hospital outcomes of TAVR compared to SAVR in the octogenarian population with HF.The National Inpatient Sample (NIS) database was used to compare TAVR versus SAVR among octogenarians with HF. The primary outcome was in-hospital mortality. The secondary outcome included acute kidney injury (AKI), cerebrovascular accident (CVA), post-procedural stroke, major bleeding, blood transfusions, sudden cardiac arrest (SCA), cardiogenic shock (CS), and mechanical circulatory support (MCS).A total of 74,995 octogenarian patients with HF (TAVR-HF n = 64,890 (86.5%); SAVR n = 10,105 (13.5%)) were included. The median age of patients in TAVR-HF and SAVR-HF was 86 (83-89) and 82 (81-84) respectively. TAVR-HF had lower percentage in-hospital mortality (1.8% vs. 6.9%;p 0.001), CVA (2.5% vs. 3.6%; p = 0.009), SCA (9.9% vs. 20.2%; p 0.001), AKI (17.4% vs. 40.8%); p 0.001), major transfusion (26.4% vs 67.3%; p 0.001), CS (1.8% vs 9.8%; p 0.001), and MCS (0.8% vs 7.3%; p 0.001) when compared to SAVR-HF. Additionally, post-procedural stroke and major bleeding showed no significant difference. The median unmatched total charges for TAVR-HF and SAVR-HF were 194,561$ and 246,100$ respectively.In this nationwide observational analysis, TAVR is associated with an improved safety profile for octogenarians with heart failure (both preserved and reduced ejection fraction) compared to SAVR.

Highlights • Choledochal cyst is a rare malformation of the common bile duct causing jaundice in the pediatric group. • Diagnosis can easily be made using abdominal ultrasonography, hence a high degree of suspicion is needed among clinicians. • Surgery, open or laparoscopic, remains the core management depending upon the availability of the resources and expertise., Introduction Choledochal cyst is a rare common bile duct malformation that usually presents in the pediatric group with abdominal pain, distension, and jaundice. The pathophysiology remains unclear for the cause, and surgery aims to restore biliary enteric drainage. Case presentation We present a six-year-old female who presented with gradual abdominal distention associated with jaundice. Abdominal ultrasound was suggestive of choledochal cyst, and CT-scan confirmed the diagnosis. She was operated on successfully and fared well. Conclusion Choledochal cysts are a rare entity of common bile duct malformations and should be considered as a differential diagnosis in the pediatric age group. Diagnosis can be easily made by non-invasive and in-expensive radiologic modalities like ultrasonography in resource-limited settings.

The choice of the flow velocity in EGR thus becomes important since higher injection rates could lead to premature mixing of the fluids and lower injection rates generally provide longer resident times for the fluids in contact and indirectly increases the mixing of the gases. Additionally, the medium peclet numbers mostly indicate the best injection rates that translate to a smoother displacement with a lower dispersion coefficient during the EGR process. Therefore, N2 Injection into natural gas reservoirs offers the potential to higher recovery efficiency with less mixing compared to conventional CO2 injection. The atmospheric air contained 79% of N2, making it readily available than CO2 with 400 ppm air composition. More so, N2 requires less compression ratio, which is why a lower amount of it was required to initiate much pressure in the CH4 reservoir during displacement. These made the use of N2 more economically feasible and friendly for the EGR process. A laboratory core flooding experiment was carried out to simulate the effect of injection velocity on CH4 recovery and dispersion coefficient. This was done at 40 ◦C, 1500 psig, and 0.2–1.0 ml/min injection rates. The results showed that a medium peclet number could be used to predict the best injection rate that translates to a smoother displacement with a lower dispersion coefficient during the EGR process. CH4 recovery and efficiency were highest at lower injection velocities experienced in both core samples. This could be attributed to insignificance nascent mixing observed as seen on their recorded low longitudinal dispersion coefficient results. Consequence, the experimental runs at high injection rates (0.6–1.0 ml/min) present a different scenario with lower recovery and efficiency due to their high interstitial velocities as the N2 plumes transverses into the core sample during CH4 displacement. Overall, the least methane production and efficiency were noticed in the Bandera core sample as a result of the heterogeneity effect due to the presence of higher clay contents in Bandera than Berea gray. When the capillary forces within the narrower pores in Bandera core sample were overcome, the clay particles occupied those pores thereby sealing some of the flow paths within the pore matrix. This reduces the flow channels, significantly, through which the injected N2 will flow to displace the residual CH4.

Pulsed magnets can produce magnetic fields largely exceeding those achieved with resistive or even hybrid magnets. This kind of magnet is indispensable in studies of field-induced phenomena which occur only in high magnetic field. A new high homogeneous pulsed magnet capable of producing field up to 55 T and specially designed for NMR experiments was built and tested. Experimentally observed homogeneity of magnetic field in central part of the magnet is 10 ppm over a sample volume of 2–3 mm3 at 12 T and 30 ppm at 47 T, which are the best values ever reported for a pulsed magnet. Reasons which affect the field profile and reduce homogeneity at high field are discussed.

The power efficiency of underground cables is largely affected by the thermal conductivity of the surrounding (backfill) materials hosting the cables/tubes. We are investigating the possibility to enhance thermal conduction in Al-modified clay-bentonite to be used as backfill materials. The Transient Plane Source (TPS) technique is used to measure thermal conductivity. The measurements were performed on five dry samples at room temperature. They were done on an isotropic basis using different amounts of Al concentration (0%, 6%, 8%, 13%, and 25%) of the sample weight. The results showed an overall substantial relative increase in the thermal conductivity values from 0.25 W/m-K to 0.68 W/m-K, as the Al-content increased by 25%. The estimated average U-values of these samples were in the range from 0.40 to 1.1 W/m2 K, which are directly proportional to the relative increase in the measured thermal conductivity.

The heat transfer and the U -values of wall layers in traditional North African houses in Libya have been estimated. The locally produced building materials during 1970’s were used in the construction of such buildings. These materials were limited to bricks, tiles, cement plasters, mortar and ground soils without any insulation components. The masonry construction of these houses was based on concrete-backed stone masonry made of limestone bricks joined by mortar forming the outer walls of the building envelope. Based on the periodic seasonal weather conditions, within the Libyan cost region during summer and winter, measured thermal conductivity values were used to implement such seasonal variation of heat flow and the temperature variations through the walls. The estimation of the U -values is based on measurements and calculations. The experimental measured thermal conductivity values were obtained using the Hot Disk method known as Gustafsson’s probe. The numerical calculations were done using an analytical model that considers different wall and floor constructions which are characteristics of such houses. According to the obtained results, the U -values were quite high and therefore, several suggestions have been proposed to improve the thermal loading performance that will lead to a reasonable human comfort and reduce energy consumption.

We have deposited and characterised ZnO on flexible and transparent plastic polymer. We employed a specially designed vapour phase growth system with elemental sources for zinc and oxygen and deposited thin ZnO films at temperatures below 400 °C. Basic photoluminescence characterisation confirms ZnO. Ohmic contacts were fabricated on these layers and the layers exhibit significantly high electron concentration with carrier mobility μ of up to 10.78 cm 2 V −1 s −1 . Furthermore, we show how these layers can be processed with conventional device processing techniques.

The fluorescence quenching of poly (4-methylstyrene), poly (4-methoxystyrene), poly (α-methylstyrene) and poly (4-tert-butylstyrene) by dimethyl terephthalate, diethyl terephthalate, dibutyl phthalate and dioctyl terephthalate has been investigated in solvent of different polarities. Fluorescence spectra of these derivatives reveal the presence of both monomeric and excimeric emissions in all used solvents and were affected by the type of substituent and the polarity of the solvents. Monomeric and excimeric emissions were quenched by the addition of plasticizer as electron donors and quenching efficiency was affected by the polarity of solvents as well as the molar mass of the added plasticizer. As a result of the quenching processes no exciplex emission was observed in all used solvents. Quenching parameters such as quenching rate constants and quenching cross-sections for these quenching processes were calculated in all used solvents.

In this short communication, we report on a 25-year-old male patient who presented with a longstanding painless swelling under the tongue. It was of a gradual onset and course, but 2 months before presentation it suddenly increased in size. Local examination revealed a tender firm pigmented mass in the midline of the mouth floor. The differential diagnosis included dermoid cyst, salivary glands tumours, mucocele or vascular anomaly. The investigations done were not conclusive. He underwent surgical exploration, and mycetoma was a surgical surprise. Although mycetoma is common problem in the tropics, such a presentation is a rarity. In tropical and subtropical regions, mycetoma should be considered in the differential diagnosis of oral cavity masses.

The transient plane source technique has been used for simultaneous measurements of thermal conductivity and diffusivity in the lithium–sodium sulphate system starting near 300 K. Samples with 100, 77.5, or 50% Li2SO4 behave differently from pure Na2SO4. In the first case both the thermal conductivity and the diffusivity start to increase rapidly at about 640 K, while the crystal structure remains monoclinic for Li2SO4 and trigonal for LiNaSO4. Concerning pure Li2SO4, there is an additional discontinuous increase of the two thermal parameters at the structural transition from monoclinic to cubic (fcc) at 850 K, while the temperature gradients become significantly smaller in the cubic phase than in the monoclinic one. In contrast, both the thermal conductivity and the diffusivity of Na2SO4 decrease over the whole studied temperature range, which includes the phase transitions at 474 K and 520 K. Furthermore, a corresponding study was performed for silver iodide over the range 295–640 K, i.e. on both sides of the phase transition at 420 K. There is an indication of a small decrease of the thermal conductivity and the diffusivity at the phase transition. The high temperature phases fcc Li2SO4, bcc LiNaSO4 and bcc AgI are solid electrolytes, but it is characteristic for the two sulphate phases that a coupled rotation-like motion of the sulphate ions enhances the cation migration. Obviously, such motion is also of importance for heat transport.

As is the case with the deletion of other sentence elements in Classical Arabic, object deletion is semantically marked on two levels: (I) dropping the object deliberately but functionally, (II) emptying the object slot and focusing on the verbal action. Among the functions of object deletion on the first level are: (a) brevity, (b) degradation or insult, (c) generalization, (d) ruling out a misleading interpretation which the presence of the object might cause. The second level of object deletion stresses the verbal action. In the latter, the object is not intended and the transitive verb acts as intransitive.

In some cases it is difficult to explain synchronic phonological variation, especially when multi-level/variety languages are involved, by reference to pure phonetic environments or social and stylistic contexts alone. It is proposed in this paper that the lexical conditioning hypothesis may offer a solution to these cases. It is assumed under this hypothesis that the occurrence of one phonetic variant or another is often predicted from the nature of the lexical item containing it, provided that all other variables are kept constant. Through an empirical analysis of some phonological variables in spoken Arabic, we have shown that there is some correlation between the status of the lexical item and its phonetic realization. The analysis also lends support to a number of principles of language change and variation assumed under the lexical hypothesis.

Objective The role of qat chewing, tobacco (shammah) dipping, smoking, alcohol drinking, and oral viral infection as risk factors for oral squamous cell carcinoma (OSCC) in Yemen was assessed. Study Design A total of 60 cases of OSCC and 120 age- and gender-matched controls were analyzed with respect to demographic data, history of oral habits, and the presence of human papillomavirus (HPV)-16, HPV-18, or Epstein-Barr virus (EBV) as determined by Taqman quantitative polymerase chain reaction. Logistic regression analysis was used to identify independent predictors of the disease. Results Shammah use was the only risk factor for OSCC, with an odds ratio of 12.6 (CI, 3.3-48.2) and 39 (CI, 14-105) for the ex-users and current users, respectively. The association of shammah use alone with OSCC exceeded that of shammah use in combination with qat chewing, smoking, or both. EBV infection, smoking, and qat chewing showed no association with OSCC, while neither HPV-16 nor HPV-18 were detected in any sample. Conclusions Shammah use is a major risk factor for oral cancer in Yemen.

The behaviour of Al2O3 and MgO insulated cables with four different cable diameters from 1 mm to 3 mm was investigated in the temperature range from 20°C to 800°C and under gamma dose rate exposures between 0 R/h up to 1×106R/h. Differences in the insulation resistance were found below 400°C due to the dominant gamma induced photocurrent. Between 400°C and 800°C both cable types show a very similar resistance behaviour which is influenced only by temperature.

This paper investigates the pragmatic functions of preposing(i.e. topicalizing) subject and object in standard Arabic. It begins with a distinction between two types of movement transformations or proposing processes in Arabic: obligatory and optional and points out that whereas obligatory proposing is an inherent pattern of the Arabic sentence structure and there are no special interpretations of sentence meaning incurred by it, optional preposing is semantically marked and is characterized by transformations which convey additional meanings. But although the term “topic” is essentially used to identify a particular sentential constituent, discourse analysts have been referring to “topic” as “what is being talked about in a conversation/text” (Morgan 1975). This paper shows, through examples, that Arabic grammar has recognized the close relationship between syntax and semantics and that all changes in the internal structures of Arabic sentences are motivated by a desire to express additional meanings. Also proper preposing and postposing are indicative of eloquence, good style and rhetoric. This paper then discusses the functions of proposing the subject and summarizes them in emphasis, specification and particularity and showing importance. These functions are best expressed through promise and guarantee, refuting a claim, putting an end to doubts, praising someone, seeking clarification and affirmation about the actual doer of a certain action and so on. Finally, the paper addresses the pragmatic functions of preposing the object which, through a movement transformation, either precedes the subject or both subject and verb to take sentence-initial position. It indicates that the prime functions are emphasis, specification, specialization and importance. It concludes that the notion of proposing both subject and object coincides with the Arabic tradition of starting with the more important. It also shows that “topic” is characterized in terms of the topmost element in the hierarchical representation of discourse context.