A new method for the solution of hybrid analog digital beamforming problems

By going to millimeter wave (mmWave) we can use large scale MIMO due to short mmWave wavelength to overcome path loss by using beamforming to focus power of signal to the receiver. System structure of mmWave band is different with conventional MIMO because of large scale MIMO which is leading to use many RF-chains. For this reason Hybrid structure have been proposed for large Scale MIMO. By going to Hybrid structure a new issue has been created with phase shifter constraint. In this paper we propose a novel solution to make a hybrid precoding and combing to reach high spectral efficiency. Our problem includes a maximizing Frobenius norm of multiplying five complex matrices. As constraints, all elements of some matrices must have unit norm, and also the multiplication of some matrices must have a specific Frobenius norm. A novel solution is proposed for the problem, which is gained in two steps. At the first step, we propose a new decomposition usable for kind of complex matrices which could lead to reduce the dimension of the objective function, and eliminating constraints completely and in the second step, we propose an iterated algorithm for the resulting problem. By proposing another novel technique, we show that in each iteration, the optimal problem is equivalent to a quadratic optimal problem with limitations on the vector norm, and as a result, an optimal problem is obtained quickly. Moreover, some other real examples are included to demonstrate the usefulness and effectiveness of the proposed algorithm.     

Minocycline attenuates testicular damages in a rat model of ischaemia/reperfusion (I/R) injury

Testicular torsion is a serious urological disease leading to testicular damage. This study aimed to assess the effect of minocycline on testicular ischaemia/reperfusion (I/R) injury caused by testicular torsion/detorsion. Male adult Wistar rats (n = 32) were assigned into four groups of sham, I/R, I/R + minocycline and minocycline. I/R injury was induced by two sets of surgical operations, including the rotation of the left testis (720°, counterclockwise), followed by detorsion after 4 hr. The administration of minocycline was carried out 30 min before detorsion and then continued for 8 weeks. At the end of the 8th week, rats were killed and sampling was done. Johnson's score, the height of seminiferous tubule epithelium, the mean seminiferous tubule diameter, as well as biochemical parameters, SOD, GPx and CAT, were significantly enhanced in the I/R + minocycline group compared with the I/R group. The administration of minocycline led to a marked decrease in expression levels of Caspase-3, Bax, IL-1β and TNF-α genes, and a remarkable increase in expression levels of Bcl-2, 3β-HSD and 17β-HSD3 genes compared with the I/R group. Administration of minocycline could also reduce the rate of germ cell apoptosis (TUNEL staining). Hence, minocycline was useful in the management of testicular torsion/detorsion.     

Preparation and Optimization of Chitosan/pDNA Nanoparticles Using Electrospray

Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Chitosan (CS), as a natural polymer, has received a great deal of attention as a carrier for delivery of...     

Population genetics of 30 insertion/deletion polymorphisms in the Kuwaiti population

International Journal of Legal Medicine - This study evaluates the forensic utility of the 30 insertion and deletion (indel) markers contained in the Qiagen Investigator® DIPplex kit in the...     

Gender differences in the spatial–temporal variability between walking and running

Sport Sciences for Health - The pattern of gender differences in gait variability has not yet been well examined. The aim of the present study was therefore to investigate gender differences in the...     

Efficacy and safety of Romosozumab in treatment for low bone mineral density: a systematic review and meta-analysis

Clinical Rheumatology - Osteoporosis is a chronic skeletal disease with an increasing prevalence. Romosozumab, as a monoclonal anti-sclerostin antibody with a dual function, has been produced. In...     

Grafted human chorionic stem cells restore motor function and preclude cerebellar neurodegeneration in rat model of cerebellar ataxia

Metabolic Brain Disease - Cerebellar ataxia (CA) is a form of ataxia that adversely affects the cerebellum. Cell replacement therapy (CRT) has been considered as a potential treatment for...     

Emergency endoscopic variceal band ligation in a COVID-19 patient presented with hematemesis while on mechanical ventilation

COVID-19, caused by severe acute respiratory syndrome coronavirus (SARS-CoV-2), is now a global pandemic with serious health consequences. Currently, many strict control measures are applied in health care settings, including endoscopy units, in order to limit virus spread. Several recommendations called to limit endoscopic procedures to emergent endoscopies; however, several uncertainties still exist concerning patient safety, protective measures, and infection control methods in emergency endoscopic settings. In this case report, we present a case of successful endoscopic band ligation for bleeding esophageal varices in man with COVID-19 disease who presented with an acute attack of hematemesis while on mechanical ventilation (MV). Esophago-gastroduodenoscopy was performed in the ICU room after preparing the setting, and revealed large, risky esophageal varices. Endoscopic band ligation was done with successful control of bleeding. Third-level measures of medical protection were applied for the participating medical personnel, and patient monitoring was maintained all through the procedure. After the procedure, the bleeding stopped, and the patient was vitally stable and conscious. We conclude that emergency endoscopic interventions could be performed safely with appropriate arrangements in patients with confirmed COVID-19 on MV.