Search

A battery energy storage system (BESS), due to its very fast dynamic response, plays an essential role in improving the transient frequency stability of a grid. The performance of the BESS varies with the system's installation site. Hence, the optimal location of the BESS is of utmost importance for improving transient frequency stability. Therefore, this paper presents a hierarchical approach for optimizing the BESS placement to improve a grid's transient frequency stability. In most research, frequency nadir and rate of change of frequency (ROCOF) have been considered for studying frequency stability. This paper considers two more parameters, along with frequency nadir and ROCOF, to study the transient frequency stability, settling time, and decay ratio. A novel frequency stability index (FSI) using the four transient frequency parameters has been developed. After a significant disturbance in a benchmarked test system, the FSI was used to identify the optimal location of the BESS for stabilizing the frequency. It has been observed that, after a sudden generator outage, the ROCOF and the frequency nadir improve the best when the BESS is located at the bus closest to the generator experiencing the outage. However, considering the other two parameters as well, the value of the FSI is the minimum; that is, the optimum solution is when the BESS is located at the bus that is the second closest to the generator experiencing the outage. Results of similar studies validate the proposed FSI in indicating the optimal location of the BESS in improving the transient frequency behavior of the system. [ABSTRACT FROM AUTHOR]

Recent genomic sequencing studies have provided valuable insight into genetic aberrations in head and neck squamous cell carcinoma. Despite these great advances, certain hurdles exist in translating genomic findings to clinical care. Further correlation of genetic findings to clinical outcomes, additional analyses of subgroups of head and neck cancers and follow-up investigation into genetic heterogeneity are needed. While the development of targeted therapy trials is of key importance, numerous challenges exist in establishing and optimizing such programs. This review discusses potential upcoming steps for further genetic evaluation of head and neck cancers and implementation of genetic findings into precision medicine trials.

Sarah Taha, Sarah Azzam, Mohamed Anis, Cherif Zaazou, Mohamed HosnyDepartment of Ophthalmology, Cairo University Hospital, Cairo, EgyptIntroduction: This is a prospective nonrandomized interventional clinical trial conducted to measure and verify the intended versus the achieved LASIK flap side-cut angle in two groups of patients, Femtosecond laser-assisted in-situ keratomileusis (FS-LASIK) using Wavelight FS200 (Alcon Laboratories Inc. Fort Worth, TX, USA) and the conventional mechanical microkeratme (Moria M2 90).Methods: This prospective clinical trial was conducted on 40 eyes of 20 patients (20 eyes in each group) in the interval between December 2017 and August 2018. Heidelberg anterior segment OCT was done for the patients 2 weeks postoperatively to measure the corneal flap side cut angle.Results: The achieved side-cut angles of all the patients in the first group (the femtosecond laser-assisted in-situ keratomileusis group) were equal to or more inverted than the intended angle (110–115°) in all the study candidates with a minimum angle (110°) and maximum angle (155°). Unlike the achieved side-cut angle in the second group (the mechanical microkeratome group) in which all the achieved side-cut angle were acute with a minimum angle (30°) and maximum angle (65°) which is more acute than the intended side-cut angle (70°).Conclusion: In our study we found that the femtoLASIK technology was capable of making the flap side-cut angle more obtuse than the intended angle, unlike the achieved flap side-cut angle done using the mechanical microkeratome which was more acute than the intended angle in 100% of cases.Keywords: FS-LASIK, mechanical microkeratome, corneal flap side-cut angle, >AS-OCT

Background Meningitis is inflammation of the membranes that cover the brain, spinal cord, and the intervening cerebrospinal fluid.. Aim The aim of this paper was to assess the diagnostic role of cerebrospinal lactate dehydrogenase (LDH) and serum procalcitonin (PCT) in meningitis and to differentiate septic from aseptic meningitis. Patients and methods The cases were divided into septic meningitis (group I), aseptic meningitis (group II), and meningism (group III) and 100 control cases of complaints other than central nervous system (CNS) infection. All patients were evaluated by full clinical examination, laboratory investigation (complete blood count, erythrocyte sedimentation rate, C-reactive protein, and random blood sugar, liver and renal function tests, and blood culture), lumbar puncture for cerebrospinal fluid examination, cerebrospinal LDH by spectrophotometer, serum PCT in selected patients, computed tomography, and MRI in complicated cases. Results Cerebrospinal LDH 100% of 139 cases in septic meningitis and 98% of 104 cases in aseptic meningitis were elevated above normal range. All cases of meningism show normal range. Furthermore, serum PCT testing was positive in all patients with septic meningitis, while serum PCT testing is positive in 35 (34%) patients with aseptic meningitis and negative in 69 (66%) patients and serum PCT-Q testing was negative in all patients with meningism. Controls were assessed for normal serum PCT level. Conclusion Cerebrospinal LDH can be used only as a preliminary screening test, whereas PCT-Q was a good diagnostic marker for distinguishing septic from aseptic meningitis.

Objective: To evaluate the levels of circulating sFlt-1 in pre-eclampsia (PE) and eclampsia patients and to assess its prognostic value in detection of PE complications. Methods: The present study was a prospective cohort study conducted in tertiary hospital between January and December 2016. Included patients were divided into two groups; (Group I) severe PE group and (Group II) eclampsia group. Age-, parity-, and gestational age-matched women had approached to participate in the study as a control group (Group III). Serum sFlt-1 levels were measured at inclusion and 2 days later with all basic investigations. Patients were followed up until delivery to record any complications. Correlation analysis was performed between the serum sFlt-1 levels and clinical, laboratory investigations. Receiver operating characteristic analysis was constructed for the evaluation of the area under curve (AUC) as well as the sensitivity and specificity regarding the cutoff point of sFlt-1 level that predict occurrence of complications. Results: The study included 84 women. Women with complicated severe PE showed higher sFlt-1 levels than in non-complicated cases (120.2 ± 19.6 versus 72.2 ± 19.6, p

Thirty multiparous lactating Holstein cows with an average live body weight of 642 ± 21 kg and an average daily milk yield of 30.46 ± 0.59 kg were used in this study. Cows with parities of 2 and 4 were used following their peak period, and were divided into three groups, with ten cows in each group. The control group was fed yellow corn grain rations (YCG), while for the 2nd and 3rd groups, 25 and 50% of YCG was replaced with dry sugar beet pulp (DSBP), denoted as DSBP25 and DSBP50, respectively. The contents of dry matter, organic matter, ether extract, nitrogen-free extract, and fiber carbohydrate in the experimental rations tended to decrease; however, crude protein, crude fiber, ash, and fiber fractions tended to increase in the DSBP25 and DSBP50 groups. Only crude fiber digestibility increased (p < 0.05) in the DSBP rations. Rumen pH value and concentration of ammonia nitrogen (NH3-N) decreased, while the concentration of total volatile fatty acids (TVFAs) increased in the DSBP25 and DSBP50 groups. The concentrations of total protein and globulin in blood plasma were higher (p < 0.05) in DSBP25 and DSBP50 than in YCG. However, plasma albumin concentration, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) activities were lower (p < 0.05) in DSBP50 than in YCG. Milk yield and yield of 4% fat-corrected milk (4% FCM) were higher (p < 0.05) in DSBP25 and DSBP50 than in YCG. Fat, protein, solids not fat (SNF), and total solids (TS) contents in milk increased significantly (p < 0.05) for feeding rations containing DSBP. Feed cost was reduced, but the output of milk yield increased with DSBP. In conclusion, introducing DSBP into the rations of Holstein dairy cows led to significant improvements in their productive performance.

Obesity is a major public health problem. Palatability (i.e., the reinforcing value of food, derived from orosensory cues) is a significant factor in determining food intake and contributes to increased consumption leading to obesity. The nucleus accumbens is a ventral striatal region that is important for both appetitive and consummatory behaviors and has been implicated in modulating palatability. In this study, we investigated palatability encoding in the firing of nucleus accumbens neurons in rats. Nucleus accumbens neurons with significant changes in firing rate during consummatory behavior displayed one of two principal firing patterns. Firing in one class of nucleus accumbens neurons was correlated with the palatability of sucrose reinforcers; changes in neural activity in this class consisted primarily of excitations. Within this group of neurons, a subset was sensitive to the relative value of sucrose reinforcers, as assessed by a behavioral contrast paradigm. A second and distinct population of nucleus accumbens neurons, with changes in firing that were predominantly inhibitions, was not sensitive to reinforcer palatability; rather, these inhibitions were present even during unreinforced bouts of licking. In addition, the onset of these inhibitions typically occurred before the initiation of the licking behavior itself. We propose that two primary classes of nucleus accumbens neurons contribute to neural processing immediately before and during reinforcer consumption: inhibitions related to initiation and maintenance of consummatory behaviors and excitations that encode reinforcer palatability.

Alzheimer’s disease (AD) is a progressive age-related brain disorder that slowly destroys memory, with no cure for AD currently available. Plants from the Lamiaceae have been used traditionally for improving memory. Nineteen Mentha taxa were screened for in vitro antioxidant and acetyl- (AChE) and butyryl-cholinesterase (BuChE) and histone deacetylase (HDAC) inhibition activities. Total phenolic content was assessed, together with chromatographic determination of the phenolic composition. Two species, Mentha diemenica and M. requienii, were investigated for the first time. Mints showed strong antioxidant and moderate AChE and BuChE inhibition activities. Mint extracts exhibited good HDAC inhibition activity which was strongly correlated to their biophenol content. Apigenin-7-O-β-D-diglucuronide, chicoric acid and isosakuranetin were tentatively identified as new compounds in Mentha. Our results suggest that mints provide a substantial basis for future research into AD treatment. Furthermore, we highlight that biophenol composition and bioactivity can vary according to several factors within a single taxon.

Recent genomic sequencing studies have provided valuable insight into genetic aberrations in head and neck squamous cell carcinoma. Despite these great advances, certain hurdles exist in translating genomic findings to clinical care. Further correlation of genetic findings to clinical outcomes, additional analyses of subgroups of head and neck cancers and follow-up investigation into genetic heterogeneity are needed. While the development of targeted therapy trials is of key importance, numerous challenges exist in establishing and optimizing such programs. This review discusses potential upcoming steps for further genetic evaluation of head and neck cancers and implementation of genetic findings into precision medicine trials.