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Entanglement in a time-dependent coupled XY spin chain in an external magnetic field
No full textWe consider an infinite one-dimensional anisotropic XY spin chain with a nearest-neighbor time-dependent Heisenberg coupling J(t) between the spins in presence of a time-dependent magnetic field h(t). We discuss a general solution for the sys-tem and present an exact solution for particular choice of J and h of practical in-terest. We investigate the dynamics of entanglement for different degrees of ani-sotropy of the system and at both zero and finite temperatures. We find that the time evolution of entanglement in the system shows nonergodic and critical be-havior at zero and finite temperatures and different degrees of anisotropy. The asymptotic behavior of entanglement at the infinite time limit at zero temperature and constant J and h depends only the parameter λ=J/h rather than the individual values of J and h for all degrees of anisotropy but changes for nonzero tempera-ture. Furthermore, the asymptotic behavior is very sensitive to the initial values of J and h and for particular choices we may create finite asymptotic entanglement regardless of the final values of J and h. The persistence of quantum effects in the system as it evolves and as the temperature is raised is studied by monitoring the entanglement. We find that the quantum effects dominate within certain regions of the kT-λ space that vary significantly depending on the degree of the anisotropy of the system. Particularly, the quantum effects in the Ising model case persist in the vicinity of both its critical phase transition point and zero temperature as it evolves in time. Moreover, the interplay between the different system parameters to tune and control the entanglement evolution is explored.Research Cente
Preventing of Ehrlich tumor metastasis in liver, kidney and spleen by electromagnetic field
No full textThe aim of the present work is to study the therapeutic effects of 4.5 Hz of electromagnetic radiation as a preventive agent on the metastasis of Ehrlich tumor which occurred in some organs. The tumor was implanted intramuscularly in the left thigh of mice. Sixty female Balb/c mice were used, twenty as normal group and the other forty were divided equally into 2 groups namely A and B. Group A was the control while group B was whole body exposed to square amplitude modulated waves (QAMW) of
frequency 4.5 Hz for a period of 40 h at a rate of 4 h/day starting day 11 post tumor implantation. At the end of the experiment liver, kidney and spleen were excised for all groups. Kidney and spleen were subjected to histological examination. Fragments of the freshly excised liver were subjected to histopathological examination and the other parts were used for dielectric measurements. The results of this work indicate that the treatment of Ehrlich tumor by QAMW caused a decrease in the percentage of metastasis, also there was a decrease in the values of relative permittivity, conductivity and dielectric loss of group B as compared with group A. The statistical methods and analysis for evaluation of the results were done by calculating arithmetic means and standard deviations for percentage of metastasis and dielectric measurements. It may be concluded that whole body exposure of the animals injected with Ehrlich tumor to 4.5 Hz QAMW can inhibit tumor growth in secondary sites or distant organs and can be used as preventive agent to murine metastatic development
Slip and Heat Transfer Effects on Peristaltic Motion of a Carreau Fluid
No full textAn analysis has been carried out for peristaltic flow and heat transfer of a Carreau fluid in an asymmetric channel with slip effect. The governing problem is solved under long wavelength approximation. The variations of pertinent dimensionless parameters on temperature are discussed. Pumping and trapping phenomena are studie
Entanglement dynamics of bipartite system in
No full textEntanglement plays a crucial role in quantum information protocols, thus
the dynamical behavior of entangled states is of a great importance. In this paper we
suggest a useful scheme that permits a direct measure of entanglement in a two-qubit
cavity system. It is realized in the cavity-QED technology utilizing atoms as flying
qubits. To quantify entanglement we use the concurrence. We derive the conditions,
which assure that the state remains entangled in spite of the interaction with the
reservoir. The phenomenon of sudden death entanglement (ESD) in a bipartite system
subjected to squeezed vacuum reservoir is examined. We show that the sudden death
time of the entangled states depends on the initial preparation of the entangled state
and the parameters of the squeezed vacuum reservoir
Crab digestive phospholipase: A new invertebrate member
No full textCrab digestive phospholipase (CDPL) was purified from the hepatopancreas of Carcinus mediterraneus crabs. Homogeneous enzyme was obtained after two chromatography steps: anion exchange and size exclusion HPLC column. Homogeneous CDPL has a molecular mass of 14 kDa as determined by SDS/PAGE analysis. Unlike known digestive phospholipases like porcine PLA2 (PPPL), CDPL displayed its maximal activity at 50 °C and not at 37 °C. A specific activity of 40 U/mg for the purified CDPL was measured using PC as substrate under optimal conditions (pH 8 and 50 °C) in the presence of 8 mM sodium deoxycholate (NaDC) and 10 mM CaCl2. In contrast to PPPL, purified CDPL was completely inactivated at 60 °C. The N-terminal sequence was determined by automatic Edman degradation. No similarity between 12 N-terminal amino acid residues of CDPL was found with those of known digestive phospholipases. CDPL appears to be a new member of invertebrate phospholipases, and it is potentially useful for treat phospholipid-rich industrial effluents, or to synthesize useful chemical compounds which can be used in the food industry.Persona
الحوار التعليمي منهج إسلامي
No full textالحوار في اللغة من الحور وهو : الرجوع عن الشيء إلى الشيء. ويقصد به : المُراجعة في الكلام . والجدال : من جَدَلَ الحبل إذا فَتَلَه ، أطلق على من خاصم بما يشغل عن ظهور الحق ووضوح الصواب
وبين الجدال والحوار فرق؛ فالحوار مراجعة الكلام وتبادله بين المتحاورين وصولاً إلى غاية مستنداً إلى أنه يجري بين الأصحاب أو اثنين ليس بينهما صراع ، وأما الجدال فأكثر وروده في القرآن الكريم بالمعنى المذموم وهذا الجدل حوار لا طائل من ورائه ولكن جاء الجدل أيضاً محموداً في مواضع فالجدال بالتي هي أحسن مرادف للحوار الإيجابي البناء.
ويراد بالحوار والجدال في مصطلح الناس: مناقشة بين طرفين أو أطراف، يُقصد بها تصحيح كلامٍ، وإظهار حجَّةٍ، وإثبات حقٍ، ودفع شبهةٍ، وردُّ الفاسد من القول والرأي.وقد يكون من الوسائل في ذلك : الطرق المنطقية والقياسات الجدليَّة من المقدّمات والمُسلَمات ، مما هو مبسوط في كتب المنطق وعلم الكلام وآداب البحث والمناظرة وأصول الفقه. [أصول الحوار] .
يتناول هذا البحث المعني اللغوي والتربوي للحوار وتعريفه القرآنـي والنبوي والعناصر التربوية للحوار ، ويبين أشكال الحوار المختلفة ويعرفـــه وعرض نماذج من الحوار من القرآن الكريم والسنة النبوية الشريفة وسير الصحابة d ويعطي مثالاً وتحليلاً للحوار فيعرض الحوار الخطابي وأشكاله ويمثل للحوار التعريضي من السنة النبوية الشريفة ويبيــن أهدافه ، ويضرب أمثلة للحوار التعليمي وفيها الحوار القرآني والنبوي ويحللها .
كما تناول أهداف الحوار والوسائل التعليمية في السنة النبوية الشريفـة وتناول أهداف الحوار القرآني التربوية بأنواعه وشروطه وآدابـه والخطاب الموجه إلي النبي I لإشعاره بمسؤولية التبليغ ، وتحديد طبيعة دعوته ومهمته والإجابة عن أسئلة السائلين ، والرد على المشركين والمنافقين وأهل الكتاب والحوار الموجه إلي المؤمنين لتقوية إيمانهم ، وتذكيرهم بفضل الله ونصره ودعوتهم إلي السلم وإلي تكوين المجتمع المسلم ، والاستعانة بالصبر والصلاة وتهذيب الأخلاق ، ونهيهم عـن الـولاء لليهود والنصارى ، وغير المؤمنين أو طاعتهم والحوار الموجه إلـي عـامـة الناس لدعوتهم إلي التقوى والتوحيد والإيمان بالبعث وتحذيرهـم مــن البغـي . وأخيراً تناولنا التحليل النفسي والآثار التربوية للحوار القرآنـي
The influence of dexamethasone and the role of some antioxidant
No full textBackground: Bronchial asthma is a disease characterized by paroxysmal and reversible obstruction of the airways. The imbalance between the oxidant and antioxidant system that is called oxidative stress is critical in asthma pathogenesis. It is likely, therefore, that antioxidants may be effective in the treatment of asthma. Systemic treatment with glucocorticoids has been reported to inhibit smooth muscle hypercontraction which may account partially for their beneficial effects in the treatment of asthma.
Objective: The present study was conducted in order to study the effect of dexamethasone and some antioxidant vitamins on interleukin-4 (IL-4), immunoglobulin E (IgE) and heat shock protein 70 (Hsp70) in bronchial asthma in rats, and to recognize their possible beneficial role.
Method: The study was conducted on 60 adult male albino rats randomly divided into 4 groups (15 for each group): including normal control group (group A); asthma model group where rats were sensitized by ovalbumin and challenged with antigen aerosol producing bronchial asthma (group B); asthma model group treated with antioxidant vitamins (vitamin E and vitamin C) (group C); asthma model group treated with dexamethasone (group D). Blood and lungs samples were collected from all groups.
Results and Conclusion: Our results revealed a significant decrease of serum reduced glutathione (GSH) levels among groups B, C and D as compared to group A, while there was a significant increase in group C and D as compared to group B. Antioxidant and dexamethasone treatment resulted in a significant decrease of serum IL-4, malondialdehyde (MDA), and serum IgE levels in group C and D as compared to group B. Antioxidant treatment resulted in a significant decrease of serum Hsp70 level as compared to group B, while dexamethasone treatment resulted in a significant increase of serum Hsp70 level as compared to group B. This study suggests that it is likely that a combination of antioxidant vitamins may be effective in the treatment of asthma, considering their reported effects on lowering MDA, IL-4, and IgE levels, and the similar beneficial effects of dexamethasone in addition to increasing the expression of Hsp70 in the studied model of bronchial asthma.Sabi
Catechin hydrate inhibits proliferation and mediates apoptosis of SiHa human cervical cancer cells.
No full textCatechin hydrate (CH), one of the chemical compounds in green tea, has been shown to inhibit tumor growth. In this study, we sought to characterize the DNA damage and downstream genes targeted by CH extracts using SiHa human cervical cancer cells. The efficacy of CH in killing cervical cancer cells in vitro was investigated in this study to determine whether CH could be developed as a therapeutic agent for cervical cancer. CH showed a 50% inhibition of SiHa human cervical cancer cells at a concentration of 196.07 μg/mL at 24 h. CH induced the several folds increase of caspase-3, -8 and - 9 after 24 h and 48 h; the increase of these genes may be involved in the induction of apoptosis. The analysis of apoptosis by DeadEnd terminal transferase-mediated dUTP-digoxigenin-end labeling (TUNEL) assay was used to further confirm that CH induced apoptosis. The results suggested that CH has the potential to benefit cervical cancer prevention. This is the first report that shows the possible mechanism of the anti-proliferative effects of CH in the prevention of cervical cancer in cell culture models.Further study may increase our understanding of the mechanism by which CH has an effect on cervical cancer therapy
Effect of six problematic weeds on growth and yield of wheat
No full textA field study was carried out at the Botanical Garden of the University of Punjab, Pakistan, to investigate the yield losses by 6 commonly occurring and most abundant weeds in wheat field viz., Phalaris minor Retz., Rumex dentatus L., Coronopus didymus (L.) Sm., Medicago denticulata Willd., Chenopodium album L., and Poa annua L. These weeds were grown with two commercially grown wheat varieties viz., Inqalab 91 and Punjab 96 in 1:1 weed-crop ratio. Maximum yield losses of 76% in Inqalab 91 were caused by P. annua followed by 75% by C. didymus, whereas other weeds caused 60-70% yield losses. In case of Punjab 96, maximum yield reduction of 55% was caused by R. dentatus followed by P. minor (28%), M. denticulata, C. album (23%), C. didymus (10%) and P. annua (0%). Punjab 96 proved to be the comparatively resistant against weeds than Inqalab 91.Pakistan Botanical societ
Bi-axial flexural strength of dual-polymerizing agents cemented to human dentin after photo-activation with different light-curing systems.
No full textObjectives. This study aimed to assess the bi-axial flexural strength of two dual-polymerizing resin luting agents cemented to human dentin when photo-activated with different light-curing units. Materials and methods. Two dual-cured resin cements: choice (CH) and Variolink II (VL) were tested. Hybrid composite resin (Z-250) discs (12 × 1.5 mm) were fabricated. Three types of light-curing units were used halogen-curing unit (QTH), light-emitting diode (LED) and plasma arc (PAC). Sixty dentin discs of 0.5 mm thickness were prepared from extracted human teeth. A circular mold (2.5 mm in height and 12 mm diameter) was utilized to create supporting structure for dentin, resin cement complex. The resin luting cement (0.5 mm) was placed on the previously prepared dentin discs and covered with the prefabricated composite discs. Photo-activation of cements was performed for 40 s with QTH and LED units and for 3 s with PAC. The specimens were divided into 12 groups (20 specimens for each light source). Six groups were kept in distilled water for 24 h and the rest were stored for 6 weeks. Bi-axial flexural strength was determined using Instron machine. The data was analyzed using two-way ANOVA and Tukey test for comparison. Results. The findings indicated that the bi-axial flexural strength values for both cements CH and VL were higher for 24 h over 6 weeks but not statistically significant when cured with QTH. Meanwhile, when LED light was used for photo-activation the cements, the flexural strength values reported were statistically higher of 24 h over 6 weeks storage at P = 0.4E−6 However, PAC light did not record any statistically significant difference between two duration for the CH cement although when used for polymerization of VL the reported value for 6 weeks were statistically significantly higher value than 24 h duration at P = 0.002. Conclusion. When high immediate flexural strength is preferred in clinical situation photo-activation the cements with LED reported the greatest value.King Saud Universit