The ferrimagnetic mixed spin-1/2 and spin-5/2 Ising model with a crystal field interaction in the absence and presence of a longitudinal magnetic field on a three-dimensional cubic lattice is studied ...within the framework both of the mean-field approximation (MFA) and Monte Carlo simulation (MCS). Using the MFA, we have shown the phase diagram of the model for zero magnetic field in the (anisotropy, temperature) plane in which the system exhibits first- and second-order phase transitions and critical end-points. Also, we have used the standard MCS to confirm the previous results; we have presented the temperature dependence of the sublattice and total magnetizations for different values of anisotropy in order to determine the phase diagram of the model in the absence of a longitudinal magnetic field. In addition, the influence of this last field on the magnetic properties of the model is investigated and discussed.
Objective: We sought to determine whether type and location of thromboembolic disease in the pulmonary vascular tree predicts the hemodynamic result and clinical outcome in patients undergoing ...pulmonary endarterectomy. Methods: From 1998 to 2000, 202 patients with pulmonary hypertension and pulmonary vascular resistance ranging from 194 to 2950 dynes-s-cm−5 underwent pulmonary endarterectomy. Preoperative and postoperative tricuspid valve function, pulmonary artery pressure, and pulmonary vascular resistance were determined by means of transthoracic echocardiography and measurements with a Swan-Ganz catheter (Edwards Lifesciences, Irvine, Calif), respectively. Patients underwent intraoperative classification of thromboembolism as follows: type 1 (76 patients), fresh thrombus in the main-lobar pulmonary arteries; type 2 (81 patients), intimal thickening and fibrosis proximal to the segmental arteries; type 3 (38 patients), disease within distal segmental arteries only; and type 4 (7 patients), distal arteriolar vasculopathy without visible thromboembolic disease. Results: Overall perioperative mortality was 4.5% (9/202 patients). By means of univariate analysis, patients with type 3 or 4 disease (distal pulmonary vasculopathy) had more residual postoperative tricuspid regurgitation (P <.0001), higher postoperative pulmonary artery systolic pressure (P <.0001), and greater postoperative pulmonary vascular resistance (P <.0001) compared with that seen in patients with type 1 or 2 disease, in whom thromboembolic disease was more surgically accessible. Factors such as severity of preoperative tricuspid regurgitation, patient age, and circulatory arrest time had no correlation with postoperative hemodynamic improvement. Patients with distal thromboembolic disease (type 3-4) had higher perioperative mortality, required longer inotropic support, and had longer hospital stays compared with patients with type 1 or 2 thromboembolic disease. Conclusion: The degree of improvement in pulmonary hypertension and tricuspid regurgitation after pulmonary endarterectomy is determined by the type and location of pulmonary thromboembolic disease. Classification of thromboembolism is useful for predicting patient outcome after pulmonary endarterectomy.
J Thorac Cardiovasc Surg 2002;124:1203-11
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Pulmonary endarterectomy (PTE) is the definitive treatment for chronic pulmonary hypertension resulting from thromboembolic disease. Chronic thromboembolic pulmonary hypertension is estimated to ...occur in approximately 4% of patients who have developed an acute pulmonary embolism, though the true prevalence is suspected to be much higher. Chronic thromboembolic pulmonary hypertension is characterized by intraluminal thrombus organization, fibrous stenosis, and vascular remodeling of pulmonary vessels. PTE is an operation considered to be a curative for this affliction and is therefore superior to transplantation. The procedure involves the removal of organized and incorporated fibrous obstructive tissue from the pulmonary arterial tree and is a true endarterectomy, not an embolectomy. Surgical outcomes with respect to functional status, quality of life, hemodynamics, right ventricular function, and gas exchange are favorable. Preoperative hemodynamic severity and site of anatomical obstruction are key predictors of postoperative outcome. This article focuses on the surgical techniques and outcomes of patients undergoing PTE for chronic thromboembolic pulmonary hypertension and discusses the currently known factors that affect survival after this operation.
Chronic thromboembolic pulmonary hypertension (CTEPH) is a treatable form of pulmonary hypertension and right heart failure. CTEPH (group 4 pulmonary hypertension) is caused by persistent organized ...thromboembolic obstruction of the pulmonary arteries from incompletely resolved acute pulmonary embolism. CTEPH also may present without prior VTE history, which can contribute to its underrecognition. The true incidence of CTEPH is unclear, but is estimated to be approximately 3% after acute pulmonary embolism. V˙/Q˙ scintigraphy is the best screening test for CTEPH, with CT scan imaging and other advanced imaging methods now playing a larger role in disease detection and confirmation. Perfusion defects on V˙/Q˙ scintigraphy in the setting of pulmonary hypertension are suggestive of CTEPH, but pulmonary angiography and right heart catheterization are required for confirmation and treatment planning. CTEPH potentially is curative with pulmonary thromboendarterectomy surgery, with mortality rates of approximately 2% at expert centers. Advances in operative techniques are allowing more distal endarterectomies to be performed successfully with favorable outcomes. However, more than one-third of patients may be considered inoperable. Although these patients previously had minimal therapeutic options, effective treatments now are available with pharmacotherapy and balloon pulmonary angioplasty. Diagnosis of CTEPH should be considered in all patients with suspicion of pulmonary hypertension. Treatments for CTEPH have advanced with improvements in outcomes for both operable and inoperable patients. Therapy should be tailored based on multidisciplinary team evaluation to ensure optimal treatment response.
Introduction. Academic achievement is reflected in marks (points) achieved in the disciplines studied and it assumes that the student has acquired the required set of skills and knowledge, which he ...or she can use while performing educational and professional tasks after learning a particular discipline or a group of disciplines. This means that the concept of “academic achievement” represents measuring the student’s ability to comprehend academic programmes in the class or independently.The aims of the present research were the following: to determine the ability of students to be active users of educational databases and their elements, which are considered to be effective especially in this type of educational activity; to identify the opportunities to improve academic achievement and the quality of academic curriculum implementation (in accordance with the necessary content) through digital educational content.Methodology and research methods. The present research is based on the field survey methodology. Empirical data were collected through questionnaires and face-to-face interviews. The validity of the collected material was verified through the method of mathematical statistics.Results and scientific novelty. It is known that information technology today is one of the most important factors, which can have a powerful impact on the quality of the education system in universities. The research conducted at the Northern Border University (Arar, Saudi Arabia) investigated the following questions: how the databases available at the Saudi Digital Library assist students of various specialties (faculties) in their studies; what the real contribution of the databases to the training of future professionals is; how learners define their goals and needs by using these databases. The processed questionnaire and interview results demonstrated that for most students e-learning content is not a tool to improve academic performance. The students’ satisfaction with the offered e-learning content was very low. Meanwhile, the students noted that they needed accessible and quality digitised educational information. However, they lack the information competency to find, store and apply information in its various forms. This competency is not limited only to the skills to work with the computer (all young people possess this skill today) - it includes the skills to systematise and structure the received information; critical attitudes towards it; ability to summarise and draw conclusions. It is also important to have easy and user-friendly database tools. Thus, it is necessary to provide further guidance for learners on effective work with digital databases; to develop students’ research skills; to carry out specialised workshops in order to motivate students to use digital educational resources.Practical significance. The present research materials can be useful for specialists developing university digital databases based on curricula mastered by students.
Production of microbial oil has attracted a great attention in recent years. The potential of lipid production by the yeast strains is the reason for using microorganisms for biodiesel production. ...Microbial lipid has high similarity to the oil obtained from plants and animals in type and composition. Production of oil from yeasts must be economical, so optimization of the cultivation condition to reach higher production must be done. Native oleaginous yeast,
Cryptococcus albidus
, was isolated from soil by the nitrogen-limited medium and screened by Nile red staining.
Yarrowia lipolytica
DSM 8218 was used for lipid production as a standard strain.
C. albidus
was an excellent oleaginous yeast, and the lipid quantity, dry biomass and lipid productivity of this strain were 11.81 g/l, 19.65 g/l and 60.1 %, respectively, in shaking flask cultivation at 150 rpm and 25 °C in nitrogen-limited medium containing per liter 75 g glucose, 1 g (NH
4
)
2
SO
4
, 1 g yeast extract, 3 g KH
2
PO
4
, 1.5 g MgSO
4
.7H
2
O, 0.15 g CaCl
2
, 0.06 g MnSO
4
.H
2
O, 0.02 g ZnSO
4
.7H
2
O and 0.15 g FeCl
3
.6H
2
O with pH adjusted to 6.5. Fourier transform infrared spectroscopy was used for analyzing and confirming the production of microbial oil in this study.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Chronic thromboembolic pulmonary hypertension (CTEPH) is the result of incompletely resolved pulmonary emboli (PE) that lead to chronic right heart failure. The two mechanical treatment options are ...pulmonary thromboendarterectomy (PTE) and balloon pulmonary angioplasty (BPA). There are no formal criteria for BPA patient selection and treatment decisions vary according to a center's experience with BPA and PTE. We performed a retrospective review of consecutive patients treated with PTE and BPA at UCSD from March 2015 to 2021. Clinical and hemodynamic data were collected. Patients were categorized according to the rationale for BPA. One hundred fifty three patients underwent 643 BPA sessions, and 1104 patients underwent PTE. Patients selected for PTE had worse baseline hemodynamics with mean pulmonary artery pressure 41.1 ± 11.7 versus 34.6 ± 11.2 mmHg, p < 0.001. 59% of patients selected for BPA had surgically inaccessible disease, 21% had residual CTEPH after PTE, 10% had a discordance between disease burden and symptoms/hemodynamics, 7% had comorbidities that prevented PTE and 3% refused PTE surgery. 28% of patients who underwent PTE had exclusively level III or IV disease based on surgical specimen. There were no BPA procedure‐related mortalities and minor pulmonary vascular complication rates during BPA were 9.2%. The most common reason for BPA selection was surgically inaccessible disease followed by residual CTEPH after PTE. Almost one third of patients who underwent PTE had exclusively distal disease by surgical criteria and might have been directed to BPA at a less experienced surgical center.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Critical problems such as high price of fossil fuel and climate change have stirred up growing interest in providing suitable alternatives such as biodiesel and ethanol, although these alternatives ...have presented us with problems as a result of global competition in human food supply. Environmental problems, depletion of fossil fuel and industrialization inevitably highlight the demand for substituting a viable and renewable energy resource. Accordingly, isolation of oleaginous yeasts and optimization of lipid production proves to be invaluable. A total of 67 yeasts, from which 9 were oleaginous yeasts, were isolated for the purpose of this study. After lipid extraction, the best strain was selected and then identified through PCR. Optimization was done using M32 design by Qualitek-4 (W32b) software for analyzing the experiments. The results showed that Cryptococcus heimaeyensis proved to comprise lipid, dry biomass and lipid productivity of 6.75gL −1, 12.71gL−1and 53.10% in optimized conditions. The extracted lipid was analyzed by FTIR spectroscopy and gas chromatography–mass spectrometry (GC–MS). The study revealed considerable potential of oleaginous yeasts as biodiesel feedstock and also the efficiency of Taguchi design in the optimization process.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The Blume–Capel model with mixed spins S = 1 and S = 2, on
d
-dimensional hypercubic lattice, is studied using the real space renormalization group approximation and specifically the Migdal–Kadanoff ...technique. We give the phase diagrams on the (Δ
1
/|
J
|, 1/|
J
|) and (Δ
2
/|
J
|, 1/|
J
|) planes which are studied for selected values of Δ
2
/|
J
| and Δ
1
/|
J
| respectively, with first and second order phase transitions and tricritical points. Also, the associated fixed points are drawn up in a table, and by linearizing the transformation at the vicinity of these points, we determine the critical exponents for
d
= 2 and
d
= 3. In particular, we find that the system under study may exhibit reentrant phenomenon.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Aims
The purpose of this study was to identify any cases of previously undiagnosed pulmonary tuberculosis during autopsy.
Methods
This prospective study investigated a cohort of deceased individuals ...that underwent a full external and internal postmortem examination at the Forensic Medicine Centre, Dammam, Saudi Arabia. Gross pathology, histopathology and molecular pathology were used to identify pulmonary tuberculosis in forensic autopsy samples from the lungs.
Results
A total of 82 cases autopsied were included in the study. The mean ± SD age of the study cohort was 35.5 ± 10.3 years (range, 20–80 years). Males (n = 70; 85.37%) outnumbered females. The deceased were from 15 different countries. The number of Saudis was 16 (19.51%). The maximum number of non-Saudis was from India with 26 cases (31.71%). There were no cases of undiagnosed pulmonary tuberculosis detected for the first time at autopsy.
Conclusions
Although the prevalence of pulmonary tuberculosis in forensic autopsy cases in this preliminary study was nil, we recommend further studies to be conducted on a larger scale and in different autopsy centres throughout Saudi Arabia to get an insight into the burden of clinically undiagnosed tuberculosis in the entire country.
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