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The role of vegetation in the natural environment has drawn great interest recently. The vegetation can change the velocity distribution due to its additional resistance on the flow, consequently affecting the nutrient and pollutant transport, and the habitats. Due to the complexity of flow and vegetation interaction, many previous researchers have studied the flow structure of channels with uniform vegetation. Few studies have been done on the flow of open channels partially covered vegetation of different heights on one side of the channel, which commonly exists in natural rivers. Through novel experiments for such a vegetated flow, this paper shows the influence of different layered vegetation on the velocity profile and discharge, which indicates that the velocity in the vegetation zone is significantly smaller than that in the free-flow zone and that the velocity profiles in the short and tall vegetation zones are very different. The flow through the free-flow zone is dominant (about 75%) despite its half width, and its discharge percentage slightly decreases as increasing flow depth.

Many rivers and wetlands have vegetation. The effect of riparian vegetation on ecological and flow process in channels has become increasingly important in river flood risk and aquatic environmental management. Most previous studies have been done on the flow structure of vegetation of the same height which is not realistic in natural rivers. There are only a few studies on flows with a mixing array of short and tall vegetation under either submerged or emergent flow condition. This paper is to undertake a novel experimental study on a flow with double-layered vegetation under submerged and emergent conditions, which often occur in most rivers. Two different heights of dowels, 10 cm and 20 cm, were used in the water flume to represent the short and tall vegetation respectively, and they were allocated on one side of the flume. Experiments in two flow depths were undertaken to represent different submergence ratios of vegetation, and velocities at various locations were measured by Acoustic Doppler Velocimetry (ADV) and propeller velocimetry. Experimental results show that the velocity profile is almost uniform within the depth of short vegetation in different configurations. The velocity starts to increase in the region near the edge of short vegetation, and then followed by a rapid increase through the height of tall vegetation to the free surface. Meanwhile, a strange shear layer exists laterally between vegetation and non-vegetation, showing that the vegetation significantly reduces the velocity of flow.

Cigarette smoking is known to be a risk factor for the development of pulmonary tuberculosis; the management of the disease offers a good opportunity for smoking prevention. The aim of this study was to evaluate attitudes and knowledge of Moroccan respiratory physicians towards smoking in the management of patients with tuberculosis and the feasibility of integrating anti-smoking interventions into the national anti-TB program (PNLAT). A questionnaire was administered using a phone interview to Moroccan respiratory physicians practicing at the Tuberculosis and Respiratory Diagnostic Centre (CDTMR). 75 respiratory physicians answered the questionnaire representing 83.3% of all those approached. The rate of smoking in medical doctors was 10.7%. 66.7% of those interviewed considered that smoking increases the incidence of tuberculosis while 96% believed that smoking would worsen the pathology. More than 84% inquired about the smoking habits of their patients. Only 5.3% believed that they were well trained to help smokers to stop. 78.7% recognized the desirability of integrating a systematic smoking cessation program into the national anti-TB strategy. The rate of smoking among patients with TB is considered high by Moroccan doctors caring for the condition. However, they do not feel that they are sufficiently trained in smoking cessation techniques to help their patients. Therefore, education on smoking cessation needs to be integrated into the national anti-TB strategy.

We report an exceptional case of hemoptysis observed in a 38-year-old woman with an uneventful past history. Bronchial fibroscopy demonstrated the presence of a leech attached to the laryngeal orifice. This condition is common in endemic areas but is underdiagnosed. The association of hemoptysis, voice alterations, and difficult respiration are suggestive signs. Extraction should be achieved rapidly to avoid death due to acute respiratory failure.

This article in addition of reviewing the current techniques of surgical treatment of femoral neck fractures, also presents a newly devised technique, in which by anterior approach the pediculated muscle bone graft from the anterior part of the greater trochanter with attached gluteus medius insertion is placed at anterosuperior part of the fractured femoral neck (type 3 & 4 Garden and old neglected fractures). This paper reviews the older techniques of Judet and Meyer in which the pediculated bone graft is taken from quadratus femoris insersion and placed posteriorly to the femoral neck which may compromise the important vascular supply (posterior subsynovial retinacular artery) posteriorly to the neck. The new anterior technique has been used for 20 patients successfully for the first time in department of orthopaedic surgery in Imam Reza Medical Center. In Mashhad-Iran from 21/3/93. The ultimate analysis of results will be possible 3 years after operation.