Hydrogen Energy Storage

The dominating trend of variable renewable energy sources (RES) continues to underpin the early retirement of baseload power generating sources such as coal, nuclear, and natural gas steam generators; however, the need to maintain system reliability remains the challenge. Implementing energy storage with conventional power plants provides a method for load leveling, peak shaving, and time shifting allowing power quality improvement and reduction in grid energy management issues, implementing energy storage with RES smooth their intermittency, by storing the surplus in their generation for later use during their shortfall, thus enabling their high penetration into the electricity grid. Energy storage technologies (EST) can be classified according to many criteria like their application (permanent or portable), capacity, storage duration (short or long), and size (weight and volume). EST suited for short duration storage and low-to-medium power outputs are seen performing better in improving power quality, while those providing medium-to-high power outputs with long durations are seen better suited for energy management of electrical networks. With the growing deployment of renewable energy systems, EST must be utilized to allow the grid to absorb the increased integration of RES generation. The recent advances in hydrogen energy storage technologies (HEST) have unlocked their potential for use with constrained renewable generation. HEST combines hydrogen production, storage, and end use technologies with the renewable generation either in a directly connected configuration or in an indirectly connected configuration via the existing power network. This chapter introduces the hydrogen energy storage technology and its implementation in conjunction with renewable energy sources. The efficiency of renewable hydrogen energy storage systems (RHESS) will be explored with a techno-economic assessment. A levelized cost (LC) model that identifies the financial competitiveness of HEST in different application scenarios is given, where five scenarios are investigated to demonstrate the most financially competitive configuration. To address the absence of a commercial software tool that can quickly size an energy system incorporating HEST while using limited data, a deterministic modeling approach that enables a quick initial sizing of hybrid renewable hydrogen energy systems (HRHES) is given in this chapter. This modeling approach can achieve the initial sizing of a HRHES using only two input data, namely the available renewable energy resource and the load profile. A modeling of the effect of the electrolyzer thermal transients at start-up, when operated in conjunction with an intermittent renewable generation, on the quantity of hydrogen produced is also given in this chapter

The Perspective of Leader-Member Exchange and Its Relation with Workplace Empowerment and Organizational Citizenship Behavior among Nurses

Context: Leader-member exchange captures the impact of nurses’ perceptions of support from their supervisors’ high-quality relationships, which may promote extra-role behaviors, enabling increased job satisfaction and workplace empowerment and nurses` organizational citizenship behavior.Aim: Assess the perspective of leader-member exchange and its relation with workplace empowerment and organizational citizenship behavior among nurses. Methods: A descriptive correlational design was used to achieve the aim of the study. This study was conducted at Benha University Hospital in general medical and surgical units. A Convenient sample consisted of 190 nurses who were working in the study setting, as mentioned earlier. Three tools were used to collect the data; Subordinate (LMX-MDM) survey portion, Condition of Work Effectiveness Questionnaire (CWEQ), and Organizational Citizenship Behavior Scale. Results: The findings of this study indicated that more than half of nurses (54.7%) reported that they had a high-quality relationship with their supervisors, and 71.1% of nurses had a moderate level of workplace empowerment. Also, more than half of nurses (51.1%) had a moderate level of organizational citizenship behavior.Conclusions: There was a highly statistically significant positive correlation between the total score of leader-member exchange and total workplace empowerment, total organizational citizenship behavior. Also was a highly statistically significant positive correlation between total workplace empowerment, total organizational citizenship behavior. The study recommended that hospital management needs to focus on involving staff nurses in the political processes in an organization and keep them informed about significant changes in the organization and have a protective attitude toward it

Role of N-terminal pro B-type natriuretic peptide in acute exacerbation of chronic obstructive pulmonary disease

AbstractObjectivesAcute exacerbation of chronic obstructive pulmonary disease (AECOPD) is a major public health problem. Recognition of comorbid heart dysfunction in such patients is often difficult. The aim of this work is to evaluate the role of N-terminal pro B-type natriuretic peptide (Nt-pro BNP) in AECOPD with respiratory failure.Patients and methodsThis study was conducted on 20 patients with AECOPD and respiratory failure. All patients were subjected to history taking, clinical examination, routine laboratory investigations, arterial blood gases analysis, echocardiography and estimation of plasma level of NT-pro BNP.ResultsPatients were classified into 3 groups: Group I: those without heart dysfunction (40%), Group II: those with diastolic heart failure (40%), and Group III: those with systolic heart failure (20%). NT-pro BNP mean±SD in group I was 673.38±416.02, in group II 1962±847.88, and in group III 6776.75±1433.59pg/ml. There was a statistically significant difference between the three groups (p=0.001). NT-pro BNP showed a statistically significant inverse correlation with pH (p=0.005), ejection fraction (p=0.007) and a direct one with both left ventricular systolic (p=0.008) and diastolic (p=0.016) dimensions and E/A (p=0.016). The NT-pro BNP significantly decreased after recovery from AECOPD (p=0.030). The receiver operating characteristic curve demonstrated a ruling out of LV dysfunction in AECOPD of a sensitivity of 100% and a specificity of 60%; and a ruling in of a sensitivity of 48% and a specificity of 67%.ConclusionPlasma BNP is usually elevated in AECOPD and is related to right or left ventricular systolic or diastolic dysfunction

Plasmids for Optimizing Expression of Recombinant Proteins in <em>E. coli</em>

Plasmids are important vectors for the transfer of genetic material among microbes. The transfer of plasmids causes transmission of genes involved in pathogenesis and survival, to the host bacteria leading to their evolution and adaptation to diverse environmental conditions. A large number of plasmids of varying sizes have been discovered and isolated from various microorganisms. Plasmids are also valuable tools to genetically manipulate microbes for various purposes including production of recombinant proteins. Escherichia coli is the most preferred microbe for production of recombinant proteins, due to rapid growth rate, cost-effectiveness, high yield of the recombinant proteins and easy scale-up process. Several plasmids have been designed to optimize the expression of heterologous proteins in E. coli. In order to circumvent the issues of protein refolding, the codon usage in E. coli, the absence of post-translational modifications, such as glycosylation and low recovery of functionally active recombinant proteins, various plasmids have been designed and constructed. This chapter summarizes the recent technological advancements that have extended the use of the E. coli expression system to produce more complex proteins, including glycosylated recombinant proteins and therapeutic antibodies

Video assisted minimally invasive mitral valve replacement in rheumatic valve disease.

Objective: Assessment early outcome of video assisted minimally invasive mitral valve replacement, in rheumatic valve disease. Also, to evaluate early postoperative quality of life by SF 36 questionnaire. Methods: This is a prospective single center study which was conducted on 20 rheumatic heart patients, in Egypt; during the period from October 2015 to June 2018. The main pathological lesion was sever mitral regurgitation (MR), mitral stenosis (MS) or both. Patients underwent video assisted minimally invasive mitral valve replacement, through a right mini thoracotomy. 13 patients (65%) were via infra-mammary incision, 4 patients (20%) were via periareolar incision and 3 patients (15%) were via limited right anterolateral mini-thoracotomy. Results: Mean length of surgical incision was (6.60 ± 1.35 cm). Mean duration of operation, cardiopulmonary bypass, and cross clamp times were (4.32 ± 1.08 hr.), (2.85 ± 0.75 hr.) and (1.78 ± 0.47 hr.) respectively. ICU stay was 2.35 ± 1.14 days and Hospital stay was 6.45 ± 1.43 days. The mean amount of blood loss was 398.50 ± 245.79 ml with two patients of bleeding requiring re-opening. At discharge, all patients had normal mitral prosthetic valve function with no or trivial regurgitation, as shown by echocardiographic studies. The postoperative quality of life revealed faster recovery of usual activities. Conclusions: Video assisted minimally invasive mitral valve surgery in the surgically challenging rheumatic valve disease has less surgical trauma, blood loss and pain, which translates into short hospital stay, rapid return to normal activities, less use of resources

Exhaled breath condensate nitric oxide end products and pH in controlled asthma

AbstractObjectivesAsthma imposes a growing burden on the society in terms of morbidity, quality of life, and healthcare costs. It has the highest morbidity amongst inflammatory lung diseases and its prevalence continues to increase over the world. Inquiry into recent day or nighttime symptoms alone underestimates the burden of asthma and may lead to inadequate treatment of asthma. The aim of the present work is to evaluate the role of nitric oxide (NO) and hydrogen ion concentration (pH) levels in exhaled breath condensate (EBC) in cases of controlled bronchial asthma.Patients and methodsThe present study was conducted on 49 controlled asthmatic patients and 12 control subjects. All patients were subjected to thorough history taking, complete clinical examination and plain postero-anterior chest X-ray. All asthmatics and control subjects were subjected to routine laboratory investigations, spirometric study, EBC collection, processing and analysis for its content of both nitric oxide end products: nitrite and nitrate (NOx) and pH.ResultsAll asthmatics represented Group IT which was further divided into Group Ia: 34 patients on regular inhaled corticosteroid (ICS) therapy and Group Ib: 15 patients on no regular therapy. The control subjects represented Group II. The forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), FEV1/FVC, peak expiratory flow rate (PEFR) and forced expiratory flow during the middle portion of a forced expiration (FEF 25–75%) were significantly lower in asthmatics than control subjects. The EBC-NOx mean±SD in μmol/L in Group IT (5.99±1.63), in Group Ia (5.27±1.26) and in Group Ib (7.63±1.15) were significantly higher than in Group II (3.66±0.67) with, respectively (p=0.000), (p=0.000) and (p=0.000); and was significantly higher in Group Ib than Group Ia (p=0.000). The EBC-pH mean±SD in Group IT (7.32±0.27), in Group Ia (7.35±0.25) and in Group Ib (7.27±0.3) were significantly lower than in Group II (7.82±0.09) with, respectively (p=0.000), (p=0.000) and (p=0.000); with no significant difference between Group Ia and Group Ib. The EBC-NOx was significantly directly correlated to eosinophils count (p=0.017) and neutrophils count (p=0.002); and inversely correlated to FEV1 (p=0.016), FEV1/FVC (p=0.001), PEFR (p=0.030) and EBC-pH (p=0.003). The EBC-pH was significantly inversely correlated to eosinophils count (p=0.017) and neutrophils count (p=0.036); and directly correlated to FVC (p=0.004), FEV1 (p=0.004) and PEFR (p=0.000).ConclusionEBC-NOx is significantly higher and EBC-pH is significantly lower in asthmatic patients than in control subjects. Asthmatics receiving ICS have a lower EBC-NOx level than those not. EBC-NOx and EBC-pH were significantly correlated and both of them showed significant correlations with spirometric parameters of airway obstruction

Metabolic Syndrome and Its Components : Secondary analysis of the World Health Survey, Oman

Objectives: The study aimed to describe the prevalence of metabolic syndrome (MS) and its components among Omani adults. Methods: The 2008 Oman World Health Survey dataset was used to determine the national prevalence of MS. Logistic regression using all key sociodemographic, clinical and behavioural variables was used to identify the associations of independent variables with MS. Results: The age-adjusted prevalence of MS was 23.6%. MS was significantly associated with age, marital and work status and wealth level. MS was more common for people aged 50 years and older compared to the youngest cohort (OR 3.6, CI: 2.4–5.3; P &lt;0.001) and in people who were married or employed (OR 1.6, CI: 1.3–2.1; P &lt;0.001 and OR 1.3, CI: 1.1–1.8; P = 0.043, respectively) compared to their unmarried and unemployed counterparts. MS was also more common in people in the second lowest wealth quintile (OR 1.6, CI: 1.2–2.2; P = 0.05) compared to the lowest quintile and in those who sat for more than six hours per day (OR 1.3, CI: 1.1-1.7; P = 0.035). Conclusion: One in four adults had MS in Oman. This may fuel the epidemic of non-communicable diseases (NCDs) in Oman, particularly given the increasingly elderly population. Urgent action is required to ensure quality patient care at all levels of the healthcare system. Further research on behavioural risk factors is needed. Developing and implementing a multisectoral strategy to prevent NCDs should be at the top of the current health agenda for Oman

Trends in the Risk for Cardiovascular Disease among Adults with Diabetes in Oman

Objectives: This study aimed to investigate trends in the estimated 10-year risk for developing cardiovascular disease (CVD) among adults with diagnosed diabetes in Oman. In addition, the effect of hypothetical risk reductions in this population was examined. Methods: Data from 1,077 Omani adults aged ≥40 years with diagnosed diabetes were collected and analysed from three national surveys conducted in 1991, 2000 and 2008 across all regions of Oman. The estimated 10-year CVD risk and hypothetical risk reductions were calculated using risk prediction algorithms from the Systematic COronary Risk Evaluation (SCORE), Diabetes Epidemiology Collaborative Analysis of Diagnostic Criteria in Europe (DECODE) and World Health Organization/International Society of Hypertension (WHO/ISH) risk tools. Results: Between 1991 and 2008, the estimated 10-year risk of CVD increased significantly in the total sample and among both genders, regardless of the risk prediction algorithm that was used. Hypothetical risk reduction models for three scenarios (eliminating smoking, controlling systolic blood pressure and reducing total cholesterol) identified that reducing systolic blood pressure to ≤130 mmHg would lead to the largest reduction in the 10-year risk of CVD in subjects with diabetes. Conclusion: The estimated 10-year risk for CVD among adults with diabetes increased significantly between 1991 and 2008 in Oman. Focused public health initiatives, involving recognised interventions to address behavioural and biological risks, should be a national priority. Improvements in the quality of care for diabetic patients, both at the individual and the healthcare system level, are required

Biliary fistula and late recurrence of liver hydatid cyst: Role of cysto-biliary communication: A prospective multicenter study

Background: Hydatid cyst disease (HCD) is common in certain locations. Surgery is associated with postoperative biliary fistula (POBF) and recurrence. The primary aim of this study was to identify whether occult cysto-biliary communication (CBC) can predict recurrent HCD. The secondary aim was to assess the role of cystic fluid bilirubin and alkaline phosphatase (ALP) levels in predicting POBF and recurrent HCD. Aim: To identify whether occult CBC can predict recurrent HCD. The secondary aim was to assess the role of cystic fluid bilirubin and ALP levels in predicting POBF and recurrent HCD. Methods: From September 2010 to September 2016, a prospective multicenter study was undertaken involving 244 patients with solitary primary superficial stage cystic echinococcosis 2 and cystic echinococcosis 3b HCD who underwent laparoscopic partial cystectomy with omentoplasty. Univariable logistic regression analysis assessed independent factors determining biliary complications and recurrence. Results: There was a highly statistically significant association (P ≤ 0.001) between cystic fluid biochemical indices and the development of biliary complications (of 16 patients with POBF, 15 patients had high cyst fluid bilirubin and ALP levels), where patients with high bilirubin-ALP levels were 3405 times more likely to have biliary complications. There was a highly statistically significant association (P ≤ 0.001) between biliary complications, biochemical indices, and the occurrence of recurrent HCD (of 30 patients with recurrent HCD, 15 patients had high cyst fluid bilirubin and ALP; all 16 patients who had POBF later developed recurrent HCD), where patients who developed biliary complications and high bilirubin-ALP were 244.6 and 214 times more likely to have recurrent hydatid cysts, respectively. Conclusion: Occult CBC can predict recurrent HCD. Elevated cyst fluid bilirubin and ALP levels predicted POBF and recurrent HCD

Hepatobiliary manifestations following two-stages elective laparoscopic restorative proctocolectomy for patients with ulcerative colitis: A prospective observational study

BACKGROUNDHepatobiliary manifestations occur in ulcerative colitis (UC) patients. The effect of laparoscopic restorative proctocolectomy (LRP) with ileal pouch anal anastomosis (IPAA) on hepatobiliary manifestations is debated.AIMTo evaluate hepatobiliary changes after two-stages elective laparoscopic restorative proctocolectomy for patients with UC.METHODSBetween June 2013 and June 2018, 167 patients with hepatobiliary symptoms underwent two-stage elective LRP for UC in a prospective observational study. Patients with UC and having at least one hepatobiliary manifestation who underwent LRP with IPAA were included in the study. The patients were followed up for four years to assess the outcomes of hepatobiliary manifestations.RESULTSThe patients' mean age was 36 +/- 8 years, and males predominated (67.1%). The most common hepatobiliary diagnostic method was liver biopsy (85.6%), followed by Magnetic resonance cholangiopancreatography (63.5%), Antineutrophil cytoplasmic antibodies (62.5%), abdominal ultrasonography (35.9%), and Endoscopic retrograde cholangiopancreatography (6%). The most common hepatobiliary symptom was Primary sclerosing cholangitis (PSC) (62.3%), followed by fatty liver (16.8%) and gallbladder stone (10.2%). 66.4% of patients showed a stable course after surgery. Progressive or regressive courses occurred in 16.8% of each. Mortality was 6%, and recurrence or progression of symptoms required surgery for 15%. Most PSC patients (87.5%) had a stable course, and only 12.5% became worse. Two-thirds (64.3%) of fatty liver patients showed a regressive course, while one-third (35.7%) showed a stable course. Survival rates were 98.8%, 97%, 95.8%, and 94% at 12 mo, 24 mo, 36 mo, and at the end of the follow-up.CONCLUSIONIn patients with UC who had LRP, there is a positive impact on hepatobiliary disease. It caused an improvement in PSC and fatty liver disease. The most prevalent unchanged course was PSC, while the most common improvement was fatty liver disease