Design Methodology for the Support Beams of Internal Beds in Vertical Vessels

Author(s):  
Devki Nandan Garg

In the Petro-Chemical and other industries, vertical pressure vessels frequently have internal beds which are supported by the vessel walls. Hydrocracking and hydrotreating reactors, packed, tray and distillation columns and filters to name a few, are the common examples of such vessels. Each such bed is generally supported by a set of support beams, sectional bed supports (gratings) and a segmented circumferential ring; the ring supporting the peripheral edges of the gratings. The design details of these beds vary considerably. This paper covers a simple and user friendly procedure for the design of bed support beams, regardless of the complexities of the design details and can be applied in all the design situations. From practical stand point even number of beams are used for each bed which are symmetrically placed with respect to the vessel cross sectional centerline. It is also desirable that such beams be equally spaced to enable standard width grating (grid) sections. The spacing of beams, especially in complex hydrocracker reactor beds with high design pressures (3,000 psi) and design temperatures (900°F) is dictated by the size and weight of the largest beams and bed (grid) sections, which are installed through the top reactor man way openings.

2016 ◽  
Vol 2 (1) ◽  
pp. 62-78
Author(s):  
. Hemraj ◽  
Raj Kumar ◽  
Sourabh Kosey ◽  
Amit Sharma ◽  
Nalini Negi

To determine the most common physical side effects experienced by local chemotherapy patients. Their perceptions of these side effects and informational needs from clinical pharmacists were also evaluated. This was a single center, observational cross-sectional study conducted at department of General Surgery, Guru Gobind Singh Medical College and Hospital, Faridkot, Punjab. A face to face interview was conducted. Information collected included chemotherapy related side effects after last chemotherapy experience, the most worrisome side effects, overlooked by healthcare professionals and the preferred method, amount and source of receiving related information. In this study, hundred patients were enrolled out of them 48 were male and 52 were female. When differential calculations was done, common side effects or adverse effects of chemotherapy in the patients of breast, lung cancer, Ovarian Cancer, Colon cancer, Prostate cancer, Lymphoma Cancer, Cervix cancer where there is much irregular medicine intake 57.4% may be due to common problem of joint pain reported by all the patients under study, with the consecutive problem of nausea and vomiting. The high prevalence of chemotherapy related side effects among local patients is a major concern and findings of their perceptions and informational needs may serve as a valuable guide for clinical pharmacists and physicians to help in side effect management. This study shows the common problems reported by the patients when they are suffering from cancer condition, according to their incidence perceptions as experienced by the patient, this will allow the physician and clinical pharmacist to effectively counsel and manage the common symptoms as reported prior to its occurrence in the patient, so that withdrawal can be checked.


Author(s):  
Yasir. B. Elshambaty

Purpose this study aims to show the patterns and outcome of pediatric injury among those living in Albaha region in Saudi Arabia Methods this is a cross-sectional descriptive household-based study, included children between 0-17 years old both male and female. The data were collected with structured questionnaire between 20 Nov – 20 Dec 2018 and  analyzed with SPSS version 25 Results the total of participants was 257 injured child. 199(77.4%) are male and 58(22.6%) are female. About 44%of them were injured at pre-school level and 56% were traumatized at school age. The least incidence of injury occurred in those less than 2 yrs and higher incidence in those between 3-10 yrs old. The most common mechanism of injury was falling from height. The most affected group age by RTA accidents was 11-17 yrs old. Approximately 83% of the injured children required hospital management. Only one third of the injuries were  associated complications. The most common injured anatomic part was the upper limb and the least affected part was the spine. Only 5% of the injuries were associated with a disability and the common was loss of organ or part of it. Paralysis occurred in less than 1% and head injury resulted in disabilities more than 1%. Conclusion the vast majority of the injuries in our participants are not serious. The severe injuries were associated with RTA-related trauma. Most of injuries due to falling from height are not serious. We recommend not to allow the children to drive cars. Keywords: pediatric injuries; injury patterns; household.


2020 ◽  
Vol 22 (3) ◽  
pp. 141-145
Author(s):  
Krishna Chandra Devkota ◽  
S Hamal ◽  
PP Panta

Pleural effusion is present when there is >15ml of fluid is accumulated in the pleural space. It can be divided into two types; exudative and transudative pleural effusion. Tuberculosis and parapneumonic effusion are the common cause of exudative pleural effusion whereas heart failure accounts for most of the cases of transudative pleural effusion. This study was a hospital based cross sectional study performed at Nepal Medical College during the period of January 2016-December 2016. A total of 50 patients who fulfilled the inclusion criteria were enrolled. Pleural effusion was confirmed by clinical examination and radiology. After confirmation of pleural effusion, pleural fluid was aspirated and was analysed for protein, LDH, cholesterol. The Heffner criteria was compared with Light criteria to classify exudative or transudative pleural effusion. Among 50 patients, 30 were male and 20 were female. The mean age of patient was 45.4±21.85 years. The sensitivity and specificity of using Light criteria to detect the two type of pleural effusion was 100% and 90.9%, whereas using Heffner criteria was 94.87%, 100% respectively(P<0.01). There are variety of causes for development of pleural effusion and no one criteria is definite to differentiate between exudative or transudative effusion. In this study Light criteria was more sensitive whereas Heffner criteria was more specific to classify exudative pleural effusion. Hence a combination of criteria might be useful in case where there is difficulty to identify the cause of pleural effusion.


2018 ◽  
Vol 8 (4) ◽  
pp. 65-69
Author(s):  
Mao Nguyen Van ◽  
Dong Tran Nam

Background: Pigmented tumour of the skin is one of the common tumour in human including the benign pigmented tumours (more common) called Nevi tumours and the malignant one called melanoma which was less frequent but the most poor in prognosis. In addition, the others not belonging to these group had the same clinical appearance, so the application of histopathology and immunohistochemistry for the definitive diagnosis was indespensible. Objectives: 1. To describe the macroscopic features of the pigmented tumoral-like lesions; 2. To classify the histopathologic types of the pigmented cell tumours and the other pigmented tumours of the skin. Materials and Method: Cross-sectional research on 55 patients diagnosed as pigmented tumoral lesions by clinician, then all definitively diagnosed by histopathology combining the immunohistochemistry in difficult cases. Results: There was no difference in gender, the disease was discovered most common in adult, especially with the age over 51 years old (58.1%). the most region located was in the face accounting for 60%, following the trunk and limbs (14.6%, 12.8% respectively). All 3 malignant melanomas happened in foot. The most common color of the lesions was black (65.4%), the other ones were rose, grey and blue. Histopathology and immunohisthochemistry showed that the true pigmented cell tumours were 52.6% encompassing benign ones (Nevi tumour) (41.8%), melanoma (5.4%) and lentigo (5.4%). 47.4% was not the true pigmented cell tumour including pigmented basocellular carcinoma (36.4%) and the others less common as histiofibromas, acanthoma and papilloma. Conclusion: the pigmented tumoral-like lesions of the skin could be the true pigmented cell tumours and the others, so the application of the histopathology and the immunohistochemistry after the clinical discovery helps to determine and classify the disease definitely and for the best orientation of treatment as well. Key words: skin tumour, benign pigmented tumour (Nevi), malignant pigmented tumour (melanoma), pigmented basocellular carcinoma


2017 ◽  
pp. 46-52
Author(s):  
Thanh Thai Le ◽  
Phuong Nam Tran ◽  
Thi Ngan An Nguyen

Aims: To study outcomes of septoplasty and partial inferior turbinectomy (PIT) method, expecting leastsurgical equipment, good result, price rationalization. Methods: Prospective, cross-sectional study. Including 40 patients treated by septoplasty and PIT method. Assessment had been made after 3 months post-op. Results: The common symptoms were nasal obstruction (100%), headache (40%). The deformities of nasal septalwere deviation (42.5%), crest (30%). There were 67.5% of patients with severe bilateral hypertrophic inferior turbinate, mostly over grade II, enlargement both soft and bone parts (60%). After 3 months, the nasal obstruction and headache presented good or great results in 90% of patients, 93.7% of patients had straight nasal septaland 90% hadsmall inferior turbinate.VAS: patients’s contentment was 100%. Conclusions: The study showed that septoplasty and partial inferior turbinectomy presented good results with 87.5% after surgery and 90% after 3 months. Key words: septal deformity, hypertrophy inferior turbinate, septoplasty, partial inferior turbinectomy


2019 ◽  
Vol 16 (3) ◽  
pp. 215-223 ◽  
Author(s):  
Dejan Jakimovski ◽  
Matthew Topolski ◽  
Kana Kimura ◽  
Virja Pandya ◽  
Bianca Weinstock-Guttman ◽  
...  

Background: Studies have previously shown greater arterial and venous extracranial vascular changes in persons with multiple sclerosis (PwMS) when compared to healthy controls (HCs). Objectives: To determine the change in the number and size of secondary neck vessels in PwMS and HCs over a 5-year follow-up period. Methods: Both at baseline and follow-up, 83 PwMS and 25 HCs underwent magnetic resonance angiography (MRA) imaging and analysis. The number and cross-sectional area (CSA) of all secondary neck vessels (excluding the common/internal carotid, vertebral artery, and internal jugular vein) measured at levels from C2-T1 were determined by semi-automated edge detection/ contouring software. The longitudinal change in the number and CSA of the secondary neck vessels from the PwMS and HCs were analyzed by non-parametric Wilcoxon repeated measure. Benjamini-Hochberg procedure adjusted for false discovery rate (FDR). Results: For over 5 years, PwMS demonstrated a consistent longitudinal decrease in both the number of secondary neck vessels (Z-change between -3.3 and -5.4, q=0.001) and their CSA (Zchange between -2.9 and -5.2, q=0.004). On the contrary, the HCs did not demonstrate a significant longitudinal change in secondary neck vessels over the follow-up period. Due to the longitudinal decrease, the PwMS showed a lower number of secondary neck vessels when compared to HCs measured at follow-up (p<0.029, except for C4 with trending p=0.071). The PwMS changes were also corroborated within each MS phenotype. Conclusion: PwMS demonstrate a significant mid-term decrease in the number and the size of the secondary neck vessels. The clinical relevance of these findings and the effect on intracranial blood flow are currently unknown.


2021 ◽  
pp. 155335062098465
Author(s):  
Dong-Lai Wang ◽  
Guo-Qing Zhu ◽  
An-Quan Huang ◽  
Hong Zhang ◽  
Chuan Feng ◽  
...  

Objectives. In this study, we performed a novel type of posterior en bloc elevation cervical laminoplasty (PEEL) to keep the integrity of the posterior structure, aiming to reduce axial symptoms complicated by a conventional cervical laminoplasty procedure. Methods. Twelve human cervical cadaveric spines (C2-T1) were sequentially tested in the following order: intact condition, open-door laminoplasty (ODL) through bilateral intermuscular approach (mini-invasive ODL), PEEL, and laminectomy (LN). After bilateral transecting at the junction of lamina and lateral mass through the tubular retraction system, the PEEL procedure symmetrically elevated all the posterior structure which was further stabilized with bone grafts and titanium plates. Computed tomography (CT) scan and biomechanical testing were performed after each condition. Results. Both mini-invasive ODL and PEEL procedures were accomplished with 2 small incisions on each side. Two types of laminoplasties could enlarge the spinal canal significantly both in cross-sectional area and anteroposterior diameter comparing with intact condition. The PEEL procedure demonstrated a significantly higher enlargement rate on a canal area and a symmetrical expansion pattern. Compared with intact condition, mini-invasive ODL performed from C3-C7 demonstrated significantly decreased motion in all testing directions except the flexion range of motion (ROM); the PEEL procedure showed mild and insignificant decrease on ROM in all directions. Laminectomy resulted in a statistically significant increase in all directions except the lateral bending ROM. Conclusions. Posterior en bloc elevation cervical laminoplasty can enlarge the canal more effectively and preserve better ROM after operation than the ODL procedure. Although technically challenging, the PEEL procedure probably would decrease the common complications associated with ODL laminoplasty.


Author(s):  
Andrew Q. Philips

In cross-sectional time-series data with a dichotomous dependent variable, failing to account for duration dependence when it exists can lead to faulty inferences. A common solution is to include duration dummies, polynomials, or splines to proxy for duration dependence. Because creating these is not easy for the common practitioner, I introduce a new command, mkduration, that is a straightforward way to generate a duration variable for binary cross-sectional time-series data in Stata. mkduration can handle various forms of missing data and allows the duration variable to easily be turned into common parametric and nonparametric approximations.


2011 ◽  
Vol 8 (6) ◽  
pp. 727-735 ◽  
Author(s):  
Dennis O Dixon ◽  
Susanna Weiss ◽  
Kelly Cahill ◽  
Lawrence Fox ◽  
Joni Love ◽  
...  

Background Historically, four divisions of the National Institute of Allergy and Infectious Diseases (NIAID) that manage clinical trials and oversee data and safety monitoring have operated fairly autonomously with respect to their approaches to Data and Safety Monitoring Board (DSMB) operations. We recognized the need for a revised policy on DSMB operations in an effort to encourage greater harmonization of procedures across the four divisions. Purpose The purpose of this article is to describe the considerations that motivated the development of the new policy, summarize current DSMB policies and ongoing harmonization efforts across the four divisions, and offer some recommendations for DSMB operations in the hope that other organizations may benefit from our experience. Methods From 2005 to 2009, a working group undertook a review of DSMB responsibilities, policies, and operations. We analyzed and summarized the final policy document that the working group produced, gathered data describing current DSMB activities, and developed a tabular, cross-sectional overview highlighting how divisions are harmonizing their DSMB operations. Results In 2010, there were 44 DSMBs in NIAID monitoring 169 protocols, and those DSMBs conducted 209 reviews of the protocols. Review and analysis of DSMB practices across the four divisions have led to recommendations for efficient and successful DSMB operations: adopt an inclusive approach, whereby the trial investigators assist in the process of forming and utilizing DSMBs; structures other than DSMBs can often provide many of the features of DSMBs but with greater flexibility in membership, access to interim data, and scheduling; the trial protocol should specify what safety and other concerns should trigger a DSMB review and what data should be included in prespecified reviews; present data in thoughtful and user-friendly ways that answer specific questions; allow sufficient time to plan for working with the DSMB. Limitations We recognize that NIAID’s specific circumstances and DSMB policy may not apply to the operation of DSMBs in every organization. Nevertheless, we believe that useful lessons can be learned from our experiences and efforts toward harmonization. Conclusions Homogeneity in DSMB operations and management has appeal as a matter of organizational policy and efficiency. Some limited flexibility, as long as it honors fundamental principles of independence, confidentiality of interim trial results, and clear lines of reporting and approval, may be appropriate on occasion. NIAID’s 2009 institute-level policy established a collective understanding of the important contribution that DSMBs make to the responsible conduct of clinical trials. Thinking will continue to evolve, leading to further policy refinements and the continued assurance of patient safety in our clinical trials.


2015 ◽  
Vol 36 (2) ◽  
pp. 16-24 ◽  
Author(s):  
Florian Bauer ◽  
Julia Hautz ◽  
Kurt Matzler

Purpose – The purpose of this paper is to detect and challenge generally accepted management and consulting practice in Mergers & Acquisitions (M&As). M&As have been an important issue in strategic management and corporate development for decades. The integration process of two separate entities has been found to be of importance, and has, accordingly, received a significant amount of attention by research, management and consulting literature. Based on these insights, managers tend to rely on well-established and generally accepted rules developed by practice and consultants that should support a successful integration process and the generation of value. Nonetheless, M&As’ efforts still often fail to create value. So is the common practice of the established drivers and beneficial consequences of the integration of M&As right, or do the experiences of consultants, companies and managers reveal something different? Design/methodology/approach – To understand these challenges, the authors spent four years studying M&A projects and subsequent integration processes of more than 400 companies that engaged in M&A efforts. The data derived from four survey-based quantitative studies among more than 430 CEOs, CFOs and other senior managers in the field of M&As and personal interviews that were conducted to get in-depth insights. Findings – This extensive research on the efforts and projects of M&As over many years and including many companies reveals that successful integration processes are complex, social and culturally dependent endeavors and that the application of commonly accepted and established principles oversimplifies and disregards the interdependencies. Originality/value – The present paper unveils four established principles concerning the successful integration after M&As as tenacious myths and provides more differentiated insights into value-destroying and value-creating mechanisms in M&As.


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