Massive Deformations of Type IIA Theory Within Double Field Theory

We obtain massive deformations of Type IIA supergravity theory through duality twisted reductions of Double Field Theory (DFT) of massless Type II strings. The mass deformation is induced through the reduction of the DFT of the RR sector. Such reductions are determined by a twist element belonging to $Spin^+(10,10)$, which is the duality group of the DFT of the RR sector. We determine the form of the twists and give particular examples of twist matrices, for which a massive deformation of Type IIA theory can be obtained. In one of the cases, requirement of gauge invariance of the RR sector implies that the dilaton field must pick up a linear dependence on one of the dual coordinates. In another case, the choice of the twist matrix violates the weak and the strong constraints explicitly in the internal doubled space.Comment: Section 4 (conclusion and outlook) expanded, published versio

Duality Twisted Reductions of Double Field Theory of Type II Strings

We study duality twisted reductions of the Double Field Theory (DFT) of the RR sector of massless Type II theory, with twists belonging to the duality group $Spin^+(10,10)$. We determine the action and the gauge algebra of the resulting theory and determine the conditions for consistency. In doing this, we work with the DFT action constructed by Hohm, Kwak and Zwiebach, which we rewrite in terms of the Mukai pairing: a natural bilinear form on the space of spinors, which is manifestly $Spin(n,n)$ invariant. If the duality twist is introduced via the $Spin^+(10,10)$ element $S$ in the RR sector, then the NS-NS sector should also be deformed via the duality twist $U = \rho(S)$, where $\rho$ is the double covering homomorphism between $Pin(n,n)$ and $O(n,n)$. We show that the set of conditions required for the consistency of the reduction of the NS-NS sector are also crucial for the consistency of the reduction of the RR sector, owing to the fact that the Lie algebras of $Spin(n,n)$ and $SO(n,n)$ are isomorphic. In addition, requirement of gauge invariance imposes an extra constraint on the fluxes that determine the deformations.Comment: chapter 4 revised and expanded, references added, published versio

Electroweak Theory and Noncommutative Geometry

The noncommutative generalisation of the standard electroweak model due to Balakrishna, Gursey and Wali is formulated in terms of the derivations Der_2(M_3) of a three dimensional representation of the su(2) Lie algebra of weak isospin. A light Higgs boson of mass about 130 GeV, together with four very heavy scalar bosons are predicted.Comment: 11 pages, LATEX, no figures. Talk given at the 2nd Gursey Memorial Conference, June 2000, Istanbu

The role of lymphocyte-monocyte ratio and platelet to lymphocyte ratio in predicting risk groups in gastrointestinal stromal tumors

Aim: Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors of the gastrointestinal tract. Armed Forces Institute of Pathology (AFIP) criteria which is the basis of our study, is also known as Miettinen’s criterion is used in classification of GIST. Lymphocyte-monocyte ratio (LMR), and platelet lymphocyte ratio (PLR) have been shown as novel markers in chronic systemic inflammatory response, therefore, we aimed to study LMR levels of the subjects with moderate to high risk GIST and to compare to those in the subjects with low or very low risk GIST. Methods: Thirty GIST patients who underwent surgery were retrospectively evaluated. Patients were divided into two groups according to the AFIP risk scoring system: the first group (group 1) included very low and low risk patients and the second group (group 2) included moderate and high risk patients. Inflammatory indicators; LMR and PLR of the groups were compared. Results: LMR value was higher in Group 1 (5.25 ± 2.55) than the LMR of group 2 (2.92 ± 1.76). PLR value was significantly lower in group 1 (139.68) compared to the PLR of group 2 (185.04). Conclusion: We think that LMR is effective in identifying low and very low risk patients compared to AFIP. From this point of view, we suggest that LMR can identify high and medium risk patients by excluding low and very low risk patients and may be an independent risk factor in GIST scoring systems

Minimally invasive surgery in primary hyperparathyroidism

Aim:  To describe the general and laboratory characteristics of patients with primary hyperparathyroidism (PHPT) who underwent surgery in our clinic, as well as surgery-related morbidity. Methods: The study population were selected: Patients with clinical and radiological diagnosis of PHPT were included in the study. Minimal invasive parathyroid surgery, aimed only the affected gland, was chosen for the patients. Preoperative calcium (Ca), parathyroid hormone (PTH), and postoperative Ca and PTH levels were recorded. Preoperative sonography and scintigraphy studies to determine localization were obtained from the same database. Results: 116 patients were undergone minimal invasive surgery for hyperparathyroidism, which is mainly focused on the pathological gland. The mean preoperative PHT was 397 ng/L and postoperative PTH was 53 ng/L. Preoperative and postoperative Ca levels were 11.7 mg/dL and 9.3 mg/dL, respectively. Histopathological evaluation revealed following results: 108 patients had adenoma. None of the subjects had malignancy. The mortality rate was 0% and the morbidity was 1.7%, related to this procedure. Conclusion: According to the data in present study, we suggest that minimally invasive surgical techniques should be preferred in sake of higher success and lower postoperative morbidity in patients with a single gland disease

Cholelithiasis and gastrointestinal cancer: Is there a relationship that increases the risk of developing cancer?

Aim: To investigate the co-existence of cholelithiasis in patients with gastrointestinal (GI) cancer both in preoperative and postoperative periods. Methods: We retrospectively analyzed the data of patients who underwent GI tract cancer surgery in the general surgery clinic of a university hospital between January 2013 and December 2019 for the presence of 'cholelithiasis' in the preoperative and postoperative periods. Age, gender, tumor type and localization and presence of the cholelithiasis in the patients were determined. In addition, the cases were divided into two as upper GI tract and lower GI tract according to tumor location and the relationship with cholelithiasis was evaluated. Results: A total of 680 GI cancer patients were included in the study. Localization of GI cancers were; colon in 211 cases (31%), rectum in 195 cases (28.7%), gastric in 187 cases (27.5%), periampullary region in 55 cases (8.1%), and small intestine in 32 cases (4.7%). In the preoperative period, 69 (10.1%) patients were associated with cholelithiasis. Thirty-one (5.1%) patients had accompanying cholelithiasis in the postoperative period. Coexistence of cholelithiasis according to cancer location was not statistically significant in the preoperative and postoperative periods. Conclusions: Our available data make it difficult to distinguish the roles of cholelithiasis on gastrointestinal cancers, because no statistically causal relationship was found between cholelithiasis and gastrointestinal cancers. However, the role of asymptomatic and symptomatic stones, which may or may not require cholecystectomy, in the development of GI tract cancers should not be ignored

Surgical treatment of inguinal hernia: Our experience

Aim: In present retrospective analysis, we aimed to evaluate the treatment results of subjects with inguinal hernia whom underwent surgical repair. Methods: Surgical treatment of inguinal hernia for last 7 years have been retrospectively analyzed. Surgical procedures include anterior mesh, posterior mesh, Mc Vay, non-mesh repair, plug mesh. Results: A total of 2320 patients underwent hernia surgery were included to the study. While, 2224 of the cases were elective procedures while 96 were operated in emergency conditions. Incarceration 78 of emergent cases were incarcerated and 18 were strangulated. Patients requiring emergency surgery were significantly older than the patients underwent elective hernia repair. Duration of hospital stay was significantly longer in emergent cases compared to elective cases. Need for intestinal resection was more common in emergent cases compared to elective surgery cases. Mc Vay and plug mesh procedures were more commonly used in emergent cases compared to elective surgery cases. Intestinal laceration and development of recurrences were more common in emergent surgery cases compared to elective surgery. Conclusion: Inguinal hernia patients should be scheduled for elective surgery without delay since need for emergent surgery may increase by time and emergent cases are associated with more complications and surgical morbidity

Effects of magnesium sulphate on liver ischemia/reperfusion injury in a rat model

Aim: To investigate the protective efficacy of magnesium sulphate in a model of rat liver ischemia-reperfusion (I/R) injury. Method: 32 adult female Wistar-Albino rats (250 to 350 g) were used in this experimental study. Rats were divided into 4 groups according to liver ischemia and magnesium sulfate application methods. Group 1 (C); control, group 2 (M); magnesium sulphate, group 3 (I/R); liver I/R, group 4 (I/R+M); I/R + magnesium sulphate treated. The blood samples were centrifuged for the study of aspartate aminotransferase (AST), alanine aminotransferase, prothrombin time (PT), international normalized ratio (INR) troponin I, total antioxidant status (TAS), total oxidant status (TOS) assays. The livers of the animals were removed at the end of the study and samples were taken for histopathological examination. Results: AST and INR values were significantly decreased in I/R+M group compared to I/R group. There was no significant difference in ALT values of the groups. Although not statistically significant, the TAS values were increased in I/R + M group compared to I/R group rats. In addition, the value of TOS was found to be lower in I/R + M group rats. In the histopathological examination, the mean values of apoptosis and necrosis were lower in the IR+M group compared to the IR group. Conclusion: The main finding of the present study suggested that magnesium sulphate pretreatment moderately decreased the liver damage through its anti-inflammatory and anti-oxidant effects in a rat model of liver I/R

Beta, Dipole and Noncommutative Deformations of M-theory Backgrounds with One or More Parameters

We construct new M-theory solutions starting from those that contain 5 U(1) isometries. We do this by reducing along one of the 5-torus directions, then T-dualizing via the action of an O(4,4) matrix and lifting back to 11-dimensions. The particular T-duality transformation is a sequence of O(2,2) transformations embedded in O(4,4), where the action of each O(2,2) gives a Lunin-Maldacena deformation in 10-dimensions. We find general formulas for the metric and 4-form field of single and multiparameter deformed solutions, when the 4-form of the initial 11-dimensional background has at most one leg along the 5-torus. All the deformation terms in the new solutions are given in terms of subdeterminants of a 5x5 matrix, which represents the metric on the 5-torus. We apply these results to several M-theory backgrounds of the type AdS_r x X^{11-r}. By appropriate choices of the T-duality and reduction directions we obtain analogues of beta, dipole and noncommutative deformations. We also provide formulas for backgrounds with only 3 or 4 U(1) isometries and study a case, for which our assumption for the 4-form field is violated.Comment: v2:minor corrections, v3:small improvements, v4:conclusions expanded, to appear in Class. Quant. Gra