•Performance of DAR using diesel engine waste heat was experimentally evaluated.•Maximum COP of 0.10 obtained for the controlled exhaust flow case at 30Nm torque.•Maximum of almost 9% waste heat ...recovery is achieved for the current system.•Refrigerator reached a temperature 10–14.5°C about 3.5h depending on engine load.
The thermal performance of a diffusion absorption refrigerator (DAR) driven by the waste heat of a diesel engine exhaust gas as an energy source was investigated experimentally. The engine was tested on a bench test dynamometer with the DAR adapted to the exhaust pipe via a heat exchanger. The engine was tested for different torques (15, 30 and 45Nm). The exhaust gas flow to the heat exchanger mounted on the DAR was controlled manually using two control valves. The experimental results indicated that by controlling exhaust gas flow, the DAR system was capable to function in a broad range of engine loads. The refrigerator cabin reached a steady state temperature between 10 and 14.5°C about 3.5h after system startup, depending on engine load. The maximum coefficient of performance was 0.10 obtained for the controlled exhaust mass flow rate case at torque 30Nm after 3h from system startup. Also, a maximum of almost 10% waste heat recovery is achieved in the current system.
Elucidating the physiological mechanisms that control reproduction is an obvious strategy for improving the fertility of cattle and developing new agents to control reproductive functions. The ...present study aimed to identify kisspeptin neurons in the bovine hypothalamus, clarifying that a central mechanism is also present in the cattle brain, as kisspeptin is known to play an important role in the stimulation of gonadotropin-releasing hormone (GnRH)/gonadotropin secretion in other mammals. To characterize kisspeptin neurons in the bovine hypothalamus, the co-localizations of kisspeptin and neurokinin B (NKB) or kisspeptin and dynorphin A (Dyn) were examined. Hypothalamic tissue was collected from Japanese Black or Japanese Black × Holstein crossbred cows during the follicular and luteal phases. Brain sections, including the arcuate nucleus (ARC) and the preoptic area (POA), were dual immunostained with kisspeptin and either NKB or Dyn. In the ARC, both NKB and Dyn were co-localized in kisspeptin neurons during both the follicular and luteal phases, demonstrating the presence of kisspeptin/NKB/Dyn-containing neurons, referred to as KNDy neurons, in cows. In the POA, no co-localization of kisspeptin with either NKB or Dyn was detected. Kisspeptin expression in the follicular phase was higher than that in the luteal phase, suggesting that kisspeptin expression in the POA is positively controlled by estrogen in cows. The kisspeptin neuronal populations in the ARC and POA likely play important roles in regulating the GnRH pulse and surge, respectively, in cows.
This study aimed to investigate the effect of oral supplementation of rumen-protected L-arginine on semen quality, testes, and accessory genital glands biometry in rams. Ten apparently healthy and ...fertile rams were randomly divided into two equal groups; control, and rumen-protected L-arginine (20 mg/Kg body weight for 30 days) treated group. In all rams, ultrasonographic measurements of the testes and the accessory genital glands and blood sampling were performed at day (D)10, D20, and D30 (D0 is the start of supplementation). Semen ejaculates were collected twice/week and semen quantity, and quality was examined. Our results showed that, in the L-arginine treated group, there were significant increase in the ultrasound biometric measurement of right seminal vesicle (RSV) and right Cowper's gland (RCG) at D10, both testes, tail of the epididymis (TE), SV, and CG of both sides at D20, and of both testes, RTE, RSV, RCG, and LSV at D30. Semen quality and quantity parameters were significantly improved in L-arginine treated group. Moreover, testosterone level in the L-arginine treated group was significantly higher than that in the Control group. Serum thyroxine and glutathione peroxidase concentrations were significantly higher in the L-arginine treated group. The present study concluded that oral supplementation with rumen-protected L-arginine is beneficial in improvement of rams' fertility.
Overproduction of free radicals is controlled by antioxidant defense mechanisms. These defense mechanisms are achieved by antioxidant enzymes such as catalase (CAT). The current study aimed to assess ...the changes in steroid hormones, oxidant/antioxidants biomarkers, lipid profiles/liver functions indices, renal function biomarkers and minerals metabolism in non-pregnant, lactating or pregnant one-humped she-camels (Camelus dromedarius) pre-synchronized with controlled internal drug releasing. The study also focused on the correlational relationships between steroid hormones and the oxidant/antioxidant biomarkers, lipid profiles and liver functions indices, renal functions and mineral metabolism in these she-camels. The study was conducted on apparently healthy dromedary she-camels (n = 60) during breeding season. A sexually active camel-bull was introduced to she-camels pre-synchronized with CIDR. Fifty to sixty days after natural mating, she-camels were examined for pregnancy. She-camels were divided into three main groups according to both pregnancy and lactation as following: pregnant (PREG, n = 38) which was kept as control one, non-pregnant and lactating (LACT, n = 8), and non-pregnant and non-lactating she-camels (NPREG, n= 14). Steroid hormones, i.e., progesterone (P4), estradiol (E2) and cortisol, oxidant indictors, i.e., malondialdehyde (MDA), antioxidant biomarkers, i.e., superoxide dismutase (SOD), total antioxidant capacity (TAC), CAT and reduced glutathione (GSH), lipid profiles indices, renal functions and related minerals were assessed. The present study confirmed the efficacy of using CIDR for synchronization in she-camels. Significant elevations in serum steroids hormones in PREG compare with LACT and NPREG. The highest concentrations of MDA as lipid peroxidation and oxidative stress indictors and lowest levels of antioxidant biomarkers except for SOD, i.e., TAC, CAT and GSH, were reported in PREG compared with LACT and NPREG. PREG showed the highest liver enzymes activities and lowest total protein values. Remarkable increases in serum concentrations of renal function parameters and phosphorous (P) were observed in PREG when compared with the other two groups. The investigated she-camels revealed significant correlation between steroid hormones and the oxidant biomarkers, antioxidant biomarkers, liver functions, renal functions and minerals metabolism parameters. P4 showed positive correlations with antioxidant biomarkers, i.e., TAC, CAT and GSH, and serum aspartate aminotransferase (AST) activities, whereas negative correlations were reported between P4 and renal functions biomarkers, i.e., blood urea nitrogen (BUN), creatinine (Cr) and creatinine kinase (CK), and minerals metabolism parameters, i.e., P and magnesium (Mg), in CIDR pre-synchronized she-camels. In contrast, E2 and cortisol showed negative correlations with antioxidant biomarkers, i.e., TAC, CAT and GSH, lipid profiles/liver functions indices, i.e., AST, alkaline phosphatase (ALP) and γ-glutamyl transferase (GGT), CK and Mg, however, positive correlations were demonstrated between E2 and cortisol, and MDA, Cr and P in investigated she-camels. In conclusion, the present study confirmed the efficacy of using CIDR for synchronization in she-camels. The highest MDA levels as indictors for oxidative stress and the lowest antioxidant levels, i.e., TAC, CAT and GSH, except for SOD in pregnant she-camels, were attributable to physiological oxidative stress as excellent compensatory responses observed in the PREG group to face such a physiologic stage. Moreover, lower P levels in non-pregnant she-camels would be contributed to failure of conception or early embryonic death. The investigated she-camels revealed significant correlations between steroid hormones and the oxidant indicators, antioxidant biomarkers, lipid profile indices and renal functions biomarkers that provided better understanding for physiological stress during pregnancy in camels.
The present study investigated the effects of epidermal growth factors (EGF) and/or β-Mercaptoethanol (βME) supplementations to oocyte maturation, fertilization, and culture media on the buffalo
...embryo production. The ovaries were collected and transferred within 2 h to the laboratory. The cumulus oocytes complexes were aspirated from 3 to 8 mm diameter follicles. Firstly, EGF; 0, 10, 20, or 50 ng/mL or βME; 0, 25, 50, 100, or 200 μM were supplemented to the
maturation (TCM-199), fertilization (IVF-TALP), or culture (IVC: SOF) media. Our results revealed that supplementing EGF (20 ng/mL) to the TCM-199, IVF-TALP, or SOF media could efficiently improve the growth rates and development of buffalos' embryos, while EGF (50 ng/mL) could stimulate the embryo production only after treatment of the IVF-TALP /or SOF media, but not the IVM medium. However, βME was less efficient than EGF; it stimulated the growth rates of buffalo embryos when supplemented with the maturation and fertilization (IVF-TALP) media in a 50 μM concentration. Secondly, combined EGF (20 ng/mL) and βME (50 μM) were supplemented to the maturation media as effective concentration. The combined treatment of EGF (20 ng/mL) and βME (50 μM) showed no significant enhancing effect on the buffalo embryos compared to each alone. For future perspectives, further study is required to examine the effects of combined EGF and βME on the maturation and fertilization of buffalo oocytes at different categories of age and seasonal localities.
The possibility of delaying treatment of HCV due to severe thrombocytopenia is challenging. This study aimed to detect the prevalence of active helicobacter infection as a claimed cause of ...thrombocytopenia in a cohort of Egyptian patients with chronic active HCV awaiting combined anti-viral therapy. The study included 400 chronic HCV patients with thrombocytopenia. Laboratory investigations included liver function tests, real time quantitative PCR, reticulocytic count, ESR, ANA, bone marrow aspiration, measurement of anti-helicobacter antibodies, and helicobacter stool antigen. Positive cases for active
H. pylori
were given the standard triple therapy for 2 weeks. Helicobacter stool antigen was detected 4 weeks after termination of therapy and the change in platelet count was detected 1 month after eradication. A total of 248 out of 281 seropositive patients for
H. pylori
(88.3 %) showed positive stool antigen (
p
= 0.01). Eradication was achieved in 169 (68.1 %) patients with platelet mean count 114.9 ± 18.8 × 10
3
/μl with highly significant statistical difference from pretreatment value (49.7 ± 9.2 × 10
3
/μl,
p
= 0.000). Seventy-nine patients were resistant to conventional triple therapy and given a 7-day course of moxifloxacin-based therapy; 61 patients responded (77.1 %) with mean platelet improvement from 76.4 ± 17.4 × 10
3
/μl to 104.2 ± 15.2 × 10
3
/μl (
p
= 0.000). The non-responders showed no improvement in their platelet count (74.6 ± 20.5 vs. 73.6 ± 15.3 × 10
3
/ul,
P
= 0.5). Eradication of active
H. pylori
in HCV augments platelet count and enhances the early start of antiviral therapy.
The main challenge facing the concept of gasoline direct injection is the unfavourable physical conditions at which the premixed charge is prepared and burned. These conditions include the short time ...available for gasoline to be sprayed, evaporated, and homogeneously mixed with air. These conditions most probably affect the combustion process and the cycle-by-cycle variation and may be reflected in overall engine operation. The aim of this research is to analyze the combustion characteristics and cycle-by-cycle variation including engine-out nanoparticulates of a turbocharged, gasoline direct injected spark ignition (DISI) engine at a wide range of operating conditions. Gasoline DISI, turbo-intercooled, 1.6L, 4 cylinder engine has been used in the study. In-cylinder pressure has been measured using spark plug mounted piezoelectric transducer along with a PC based data acquisition. A single zone heat release model has been used to analyze the in-cylinder pressure data. The analysis of the combustion characteristics includes the flame development (0–10% burned mass fraction) and rapid burn (10–90% burned mass fraction) durations at different engine conditions. The cycle-by-cycle variations have been characterized by the coefficient of variations (COV) in the peak cylinder pressure, the indicated mean effective pressure (IMEP), burn durations, and particle number density. The combustion characteristics and cyclic variability of the DISI engine are compared with data from throttle body injected (TBI) engine and conclusions are developed.
The properties of nuclear matter are studied in the frame of the Brueckner theory. The Brueckner-Hartree-Fock approximation plus two-body density-dependent Skyrme potential which is equivalent to ...three-body interaction are used. Various modern nucleon-nucleon potentials are used in the framework of the Brueckner-Hartree-Fock approximation, e.g.: CD-Bonn potential, Nijm1 potential, and Reid 93 potential. These modern nucleon-nucleon potentials fit the deuteron properties and are phase shifts equivalent. The equation of state at
T
= 0, pressure at
T
= 0, 8, and 12 MeV, free energy at
T
= 8 and 12 MeV, nuclear matter incompressibility, and the symmetry energy calculation are presented. The hot properties of nuclear matter are calculated using
T
2
-approximation method at low temperatures. Good agreement is obtained in comparison with previous theoretical estimates and experimental data, especially at low densities.
Abstract
Total organic carbon has a significant impact on both chemical and biological processes occurring in sediments, while sediments texture refers to the size of the particles that make up the ...soil. Sediments samples were collected from four stations along the southern part of the Tigris River seasonally (two months per season) during the period August, 2022 to July, 2023) to measure the TOC% and determine the sediments texture. Results show that the highest percentage of total organic carbon (1.21%) was recorded in the first station in the Al-Majar station during the summer season. Also, the lowest total organic carbon value was recorded in the first station in the Al-Majar (0.18%) during the autumn season.
The study showed the presence of small amounts of clay and starting from the Al-Majar and rising down to Qurna, while the silt increases in the same direction, and it has been observed that there is a significant rise in the amount of sand from the first station and gradually decreases as we head towards the Qurna in Basra, which may be due to human activity or because of mud deposits that increase towards the south.
This work experimentally investigated the effect of fuel temperature on nano-scale particulate matter (PM) from a Direct-Injection Spark-Ignition (DISI) engine. The first part of the investigation ...focused on the effect of fuel temperature on combustion characteristics and the second part focused on the engine-out particulate matter. This study found that the injection of chilled fuel into the combustion chamber led to higher in-cylinder pressure, longer duration of combustion (DOC), lower PM number and lower Geometric Mean Diameter (GMD) of the PM than the injection of fuel at ambient temperature.
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