Control and recalibration of path integration in place cells using optic flow.

Hippocampal place cells are influenced by both self-motion (idiothetic) signals and external sensory landmarks as an animal navigates its environment. To continuously update a position signal on an internal 'cognitive map', the hippocampal system integrates self-motion signals over time, a process that relies on a finely calibrated path integration gain that relates movement in physical space to movement on the cognitive map. It is unclear whether idiothetic cues alone, such as optic flow, exert sufficient influence on the cognitive map to enable recalibration of path integration, or if polarizing position information provided by landmarks is essential for this recalibration. Here, we demonstrate both recalibration of path integration gain and systematic control of place fields by pure optic flow information in freely moving rats. These findings demonstrate that the brain continuously rebalances the influence of conflicting idiothetic cues to fine-tune the neural dynamics of path integration, and that this recalibration process does not require a top-down, unambiguous position signal from landmarks.

HP-TACO: A high-pressure triaxial compression apparatus for in situ x-ray measurements in geomaterials.

Triaxial compression experiments are commonly used to characterize the elastic and inelastic behavior of geomaterials. In situ measurements of grain kinematics, particle breakage, stresses, and other microscopic phenomena have seldom been made during such experiments, particularly at high pressures relevant to many geologic and man-made processes, limiting our fundamental understanding. To address this issue, we developed a new triaxial compression device called HP-TACO (High-Pressure TriAxial COmpression Apparatus). HP-TACO is a miniaturized, conventional triaxial compression apparatus permitting confining pressures up to 50 MPa and deviatoric straining of materials, while also allowing in situ x-ray measurements of grain-scale kinematics and stresses. Here, we present the design of and first results from HP-TACO during its use in laboratory and synchrotron settings to study grain-scale kinematics and stresses in triaxially compressed sands subjected to 15 and 30 MPa confining pressures. The data highlight the unique capabilities of HP-TACO for studying the high-pressure mechanics of sands, providing new insight into micromechanical processes occurring during geologic and man-made processes.

The Dome: A virtual reality apparatus for freely locomoting rodents.

The cognitive map in the hippocampal formation of rodents and other mammals integrates multiple classes of sensory and motor information into a coherent representation of space. Here, we describe the Dome, a virtual reality apparatus for freely locomoting rats, designed to examine the relative contributions of various spatial inputs to an animal's spatial representation. The Dome was designed to preserve the range of spatial inputs typically available to an animal in free, untethered locomotion while providing the ability to perturb specific sensory cues. We present the design rationale and corresponding specifications of the Dome, along with a variety of engineering and biological analyses to validate the efficacy of the Dome as an experimental tool to examine the interaction between visual information and path integration in place cells in rodents.

Antibacterial Prophylaxis in Emergency Surgery of Abdominal Infection.

The results of antibiotic prophylaxis in 148 patients with destructive acute surgical sicknesses of abdominal cavity being urgently operated in the Republican hospital of Baku city from 2011 to 2016 were analyzed. Sixty-five patients were in the basic group which had got as preoperative antibiotic prophylaxis 120-hour course of amoxiclav (amoxicillin in combination with clavulanic acid). Eighty-three patients were in the control group who have performed a surgical intervention with pre-operative 120-hour antibiotic prophylaxis by Claforan (cefotaxime) combining with Metrogel (metronidazole). it was showed that applying antibiotic prophylaxis using amoxiclav positively lowered the frequency of as postoperative purulent-septic complications as recurring operations to 8.1%. How to cite this article: Jamalov FH, Agayev RM, Achundov IT, Huseynov SG, Jamalova TP. Antibacterial Prophylaxis in Emergency Surgery of Abdominal Infection. Euroasian J Hepatogastroenterol, 2018;8(2):116-120.

Rare presentation of Streptococcus pneumoniae pneumonia with bacteremia and multiple subcutaneous abscesses.

Reported here is the case of an apparently immunocompetent patient with Streptococcus pneumoniae pneumonia and bacteremia who presented with abscesses in multiple soft tissue sites. This unusual presentation provided a purulent aspirate for presumptive etiologic diagnosis by a Gram-stained smear.

Organized thrombus in the ascending aorta originating from the ostium of the right coronary artery.

This case report describes the rare finding of a pedunculate thrombus in the ascending aorta originating from the ostium of the right coronary artery (RCA) detected after an inferior wall myocardial infarction in a young female. The thrombus was removed surgically during an emergency cardiopulmonary bypass procedure

Upper and lower extremity somatosensory evoked potential recording during surgery for aneurysms of the descending thoracic aorta.

Since tibial nerve somatosensory evoked potentials (SEPs) recording is influenced by hemodynamic changes and anesthetics, alterations cannot always be attributed to spinal cord ischemia, so causing false positive results. Additional recording of median nerve SEPs facilitates interpretation. From January 1988 to July 1993, 60 consecutive patients (44 men, 16 women, mean age 66 years, ranging from 26 to 83 years) underwent surgery for an aneurysm of the descending thoracic aorta using a non-heparinized left heart bypass (Biomedicus pump). In 40 patients recording of the tibial and median nerve SEPs was performed intraoperatively by stimulating both nerves alternately. In 32 patients (80%) both recordings were uneventful. In three patients (7.5%) the tibial nerve SEP temporarily disappeared due to peripheral ischemia on termination of the bypass for the creation of an open distal anastomosis. In three patients (7.5%) near loss of both tibial and median SEP recordings was caused by low blood pressure and/or anesthetics. In two patients (5%) isolated loss of the tibial nerve SEP was due to ischemia in the spinal pathway of the tibial nerve. The tibial nerve SEP signal returned to normal: in one patient after reperfusion of intercostal arteries localized within the aneurysm, in the other patient after drainage of cerebrospinal fluid (CSF). Continuous recording of both tibial and median nerve SEPs gives consistent information on spinal cord ischemia, reducing the false positive rate of the lower extremity SEP to 7.5%.