Peripheral Displacement Research Articles

PAEDIATRIC-07 IMAGING OF PINEAL REGION TUMOURS IN CHILDREN

Abstract Pineal tumors comprise between 3% and 8% of all pediatric brain tumors. Pineal region tumors can be divided into four categories: Germ cell tumors, pineal cysts, pineal parenchymal tumors, and tumors of the supporting tissues of the pineal gland or adjacent structures (such as pineal gliomas, dermoids, and epidermoids). The most common pineal region tumors are germ cell tumors, most are pure germinomas. Other variants such as nongerminomatous germ cell tumors, mixed germ cell tumors, teratomas, embryonal cell carcinoma, yolk sac tumor, and choriocarcinoma constitute the remainder. Germinomas are hyperdense on CT and enhance homogenously. The typical appearance on CT is a calcified pineal gland surrounded by noncalcified tumor. On MRI, these lesions have homogenous signal isointense to gray matter on all sequences with intense contrast enhancement. These tumors may infiltrate the thalami and midbrain. Spinal dissemination is seen in up to 36% of cases. Pineocytomas are well-differentiated tumors that retain morphologic features of the pineal parenchymal cells. They are slow-growing, circumscribed, but noncapsulated tumors. They are more commonly solid tumors, although cystic variants have been described. Solid tumors are either hypointense or isointense to gray matter and T2-hyperintense. Enhancement is homogenous and calcification is common. Cystic variants are often indistinguishable from pineal cysts. Pineoblastomas are malignant, unencapsulated tumors that resemble embryonal tumors NOS, but are distinct from such tumors in other locations due to their photosensory differentiation. On MRI, these lesions are hypointense to isointense on T1-weighted images and variable low, high, or mixed signal on T2-weighted images. They have lobulated contours and enhance homogenously. They calcify less often than pineocytomas. The “exploded pattern” of calcification with peripheral displacement of pineal gland calcification is considered more typical of pineal parenchymal tumors, differentiating them from germ cell tumors.

Mechanical Characteristics of an Open-Buried Double-Arch Tunnel during Construction

The open excavation and concealed construction method is widely adopted for the construction of bias double-arch tunnels. However, the mechanical behavior of the tunnel during the whole construction period by using the open excavation and concealed construction method is not well understood, and the basis for construction organization and optimization is lacking. Based on an open-buried double-arch tunnel on Xiajuan Road, Changsha City, China, on-site monitoring was carried out in terms of the deformation of the steel arch in the primary lining, the stress of reinforcement in the secondary lining, and the deformation of the surrounding rock during the construction process. The correlation between the vault settlement rate and the steel arch strain was analyzed. The results show that the maximum vault settlement and settling rate of the left and right caverns occur at different locations due to different supporting conditions. The peripheral displacement experiences a process of convergence inward and extension outward. The compressive steel stress in the secondary lining of the right cavern is greater than that in the left cavern, except for the points at the arch waist. The backfill above the left cavern reduces the loading on the lining of the right cavern, but it increases the loading on the left cavern. The bias effect of the open-buried double-arch tunnel is well controlled and balanced when the open excavation and concealed construction method is adopted.

Лікування дітей з перекрутом придатків матки

The diagnosis of adnexal torsion is challenging due to the absence of specific symptoms that can determine the postponing of surgery, and, as the consequence, the development of necrotic changes at adnexa. Today, the surgical treatment of patients with this pathology shifting to the ovary-sparing surgery (detorsion) despite to the presence of necrotic changes during surgery. By that, the question of the choice of the method of treatment in case of adnexal torsion still under debate between pediatric surgeons and gynecologists. Purpose - to summarize the own experience in the treatment of patients with adnexal torsion. Materials and methods. This study based on the results of the treatment of 73 patients with adnexal torsion, which were operated at 2010-2022 years. Diagnosis was established on the results of clinical investigation and ultrasonographic (US) data. It was performed 74 surgical procedures (one patient was operated on twice), among them 57 (77%) by laparoscopic and 17 (23%) open approach (laparotomy). It was 49 (66.2%) ovary-sparing procedures (detorsion with or without cystectomy) and 25 (33.8%) - adnexectomy. Results of the study were evaluated by the statistical program StatPlus: mac, AnalystSoft Inc. (version v8). Results. Mean age of patients was 11.50.5 years. Abdominal pain syndrome (in 100%) and vomiting (in 49.3%) were the main clinical appearances. Unilateral ovaria enlargement and peripheral displacement of follicles were the most frequent US findings. The absence of the blood flow was revealed in 39.5% and the whirlpool sign in 11.6% of patients. Among of all patients, simple torsion confirmed in 24.3%, while the torsion caused by cyst or dermoid tumors, revealed in 75.7% of patients. Detorsion only was performed in 24.3% of patients and in 42.5% of patients it was supplemented by cystectomy. Adnexectomy was performed in 32.2% of patients. Conclusions. The diagnosis of adnexal torsion should be considered in all females with acute abdominal pain syndrome. Ultrasonography with or without Doppler is the first-line imaging modality. Laparoscopic detorsion, simple or supplemented by cystectomy, is the method of choice in the treatment of patients with adnexal torsion. The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of all participating institutions. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.

Numerical Simulation Research on Optimization of Large Deformation Control Parameters in Layered Slate Tunnel

In order to explore the deformation characteristics of layered slate tunnels under different dip angles of rock formations, a numerical simulation research method for optimization of large deformation control parameters of layered slate tunnels is proposed. The plane deviation, plane deformation, and DP parameters of the structure are obtained through the calculation mode. When studying the effect of overlapping rock masses on the stability of thick tunnels, the incidence angle of the rock structure is assumed to be zero. The estimated thicknesses of the dolomite limestone surrounding the tunnel are 0.3 m, 0.4 m, 0.5 m, 0.6 m, 0.7 m, 0.8 m, and 0.9 m, respectively. Select the vertical displacement to be analyzed as the result of the calculation. In order to study the influence of the structural slope on the tunnel stability, the thickness of the rock layer was 0.6 m, and the structural slopes of 5°, 15°, 30°, 45°, 60°, 75°, and 85° were used for simulation calculations. During on-site construction, focus on monitoring the tunnel section deformation before the secondary lining construction. Every 10-20 m, when the surrounding rock changes, the observation section of the enclosure convergence and vault settlement is arranged, and the peripheral displacement rate and the vault settlement rate are calculated according to the observed deformation. The results show that the vertical displacement of the top of the tunnel is generally in a “V” shape, that is, the maximum settlement in the tunnel; when the layer thickness is 0.3 m, the maximum vertical displacement of the rock layer is 7.2 mm, and the total settlement in the lining support tunnel is 8.23 mm. When the layer thickness is 0.9 m, the vertical displacement of the rock layer is 5.14 mm, and the total settlement in the lining support tunnel is 5.22 mm2; when the layer thickness was changed from 0.9 m to 0.3 m, the maximum vertical displacement of the rock layer increased by 140%, and the settlement at the vault increased by 158%. At this time, the focus of tunnel support is on both sides of the lining structure and the vault with large vertical settlement. The phenomenon that the section of YK51+032 first decreases and then increases due to the sudden appearance of mud in the surrounding YK51+040, resulting in increased short-term deformation. Only the ZK49+356 section at the entrance of the left line has a large deformation due to the thin overlying stratum, and other sections are relatively consistent, indicating the reliability of the calculation results.

Optimal control and nonlinear numerical simulation analysis of tunnel rock deformation parameters

Abstract In order to study the influence of nonlinear numerical simulation on the optimal control of the tunnel rock deformation parameters, the author proposes a numerical simulation study of the deformation characteristics of the layered rock tunnel, and determines the calculation model according to the thickness of the rock mass. The estimated thicknesses of the dolomite limestone surrounding the tunnel are 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, and 0.9 m. Select the vertical displacement to analyze as a result of the calculation. In order to study the influence of the structural slope on the tunnel stability, the thickness of the rock layer was 0.6 m, and the structural slopes of 5°, 15°, 30°, 45°, 60°, 75°, and 85° were used for simulation calculations. During on-site construction, focus on monitoring the tunnel section deformation before the construction of the secondary lining. Every 10–20 m and at the change of the surrounding rock, the observation section of the surrounding convergence and vault settlement shall be arranged, according to the observed deformation, the peripheral displacement rate and the vault subsidence rate are calculated. The results show that the vertical displacement of the top of the tunnel is generally in a “V” shape, that is, the maximum settlement in the tunnel; when the layer thickness is 0.3 m, the maximum vertical displacement of the rock layer is 7.2 mm, and the total settlement in the lining support tunnel is 8.23 mm. When the layer thickness is 0.9 m, the vertical displacement of the rock layer is 5.14 mm, and the total settlement in the lining support tunnel is 5.22 mm. When the layer thickness is from 0.9 to 0.3 m, the maximum vertical displacement of the rock layer increases by 140%, and the settlement at the vault increases by 158%. The focus of tunnel support at this time is the two sides of the lining structure and the vault with large vertical settlement. For the YK51 + 032 section, the phenomenon of first decreasing and then increasing is due to the sudden mud on the surrounding YK51 + 040, which causes the short-term deformation to increase. Only the ZK49 + 356 sections at the entrance of the spider has very good deformation due to the thin overlying stratum, and other sections are similar, which shows the reliability of the calculation results.

Drosophila Nesprin-1 Isoforms Differentially Contribute to Muscle Function.

Nesprin-1 is a large scaffold protein connecting nuclei to the actin cytoskeleton via its KASH and Calponin Homology domains, respectively. Nesprin-1 disconnection from nuclei results in altered muscle function and myonuclei mispositioning. Furthermore, Nesprin-1 mutations are associated with muscular pathologies such as Emery Dreifuss muscular dystrophy and arthrogryposis. Nesprin-1 was thus proposed to mainly contribute to muscle function by controlling nuclei position. However, Nesprin-1′s localisation at sarcomere’s Z-discs, its involvement in organelles’ subcellular localization, as well as the description of numerous isoforms presenting different combinations of Calponin Homology (CH) and KASH domains, suggest that the contribution of Nesprin-1 to muscle functions is more complex. Here, we investigate the roles of Nesprin-1/Msp300 isoforms in muscle function and subcellular organisation using Drosophila larvae as a model. Subsets of Msp300 isoform were down-regulated by muscle-specific RNAi expression and muscle global function and morphology were assessed. We show that nuclei anchoring in mature muscle and global muscle function are disconnected functions associated with different Msp300 isoforms. Our work further uncovers a new and unsuspected role of Msp300 in myofibril registration and nuclei peripheral displacement supported by Msp300 CH containing isoforms, a function performed by Desmin in mammals.

Spontaneous Background and Procedure-Related Microscopic Findings and Common Artifacts in Ocular Tissues of Laboratory Animals in Ocular Studies.

Identification of test article-related microscopic findings in ocular toxicology studies requires a working knowledge of the artifacts and procedure-related or background findings commonly encountered in such studies. The objective of this article is to provide a mini-atlas of the artifacts and procedure-related or spontaneous background findings commonly observed in ocular tissues from animals in toxicology studies of ocular drug candidates. Artifacts in the eye are often related to collection or fixation procedures and include swelling and vacuolation of lens fibers, separation of the neuroretina from the retinal pigment epithelium (RPE), and vacuolation of the optic nerve. Common in-life procedure-related findings include intravitreal injection needle tracks in the sclera and ciliary body pars plana and foci of RPE hypertrophy and/or hyperpigmentation at subretinal injection sites. Common background findings include corneal mineralization, uveal mononuclear cell infiltrates, and peripheral displacement of photoreceptor nuclei in the retina. A few uncommon spontaneous background findings that may be confused with test article-related findings, such as bilateral optic atrophy in macaques, are also included.

Application Study on Treatment Technology of Geological Disasters Caused by Water and Mud Inrush in Ningchan Tunnel

In the process of tunnel construction, water and mud inrush are engineering disasters which are extremely difficult to deal with and have great harm. With Ningchan Tunnel as the background, and combined with the actual situation of the project site, the causes of water and mud inrush in tunnels with weak geological structure are analyzed. Through safety risk analysis, a comprehensive treatment scheme of “advance pipe-shed reinforcement and curtain grouting” is put forward. By selecting the accumulated vault settlement and accumulated peripheral convergence of 4 typical monitoring sections before and after treatment, the deformation laws of Ningchan Tunnel before and after treatment are summarized: The accumulated vault settlement and accumulated peripheral displacement convergence of the monitoring section after treatment is far less than those before treatment. It shows that reasonable grouting reinforcement, advance pipe-shed reinforcement and other methods are suitable for the treatment of sections with water and mud inrush, and the treatment effect is obvious. It has certain guiding significance for similar tunnel projects.

Leukemic Stress Targets the mTOR Pathway to Suppress Residual HSC in the BM Microenvironment

The remodeling of the bone marrow (BM) microenvironment that occurs along with the progressive spread of acute myeloid leukemia (AML) cells can be considered a constitutive aspect of leukemogenesis. To date most studies have focused on the functional and in part inflammatory adaptation of stroma, and its potential role in extrinsic chemotherapy resistance. Much less is known about the impact of leukemic stress on residual hematopoietic cells. We previously identified the trafficking of select microRNAs (miRs-) in extracellular vesicles (EVs) between AML cells and hematopoietic progenitor cells (HPC). These studies revealed the mechanism underlying the suppression of HPC function in the AML niche (Hornick, Doron et. al., Science Signaling 2016). Several groups, including ours also noted the relative resistance of residual hematopoietic stem cells (HSC) to elimination from the BM of xenografted animals. In the current study we set out to understand how leukemic stress in the AML xenograft niche shapes HSC fate and function. Using AML cell lines (Molm14, U937, HL60) we established NSG xenografts, systematically tracking peripheral blood AML chimerism to recover murine hematopoietic cells at low or negative tumor burden, and replicating key assays using purified EV for intrafemoral injections. In immunofluorescent studies we initially confirmed the uptake of GFP labeled xenograft-derived EVs across the spectrum of HPC and HSC (KSL/CD150+/CD48-), as well as the successive loss and peripheral displacement of HPCs, and gains in HSC frequency in the leukemic niche. These HSC were found to be enriched for G0 cell cycle status with an increase in phospho- p53, but showed no evidence of apoptosis or senescence. To understand the mechanism underlying their apparent quiescence, we performed in vitro proteomics studies of AML EV exposed HPSC identified downregulation of ribosomal biogenesis pathways. We then confirmed in vivo that residual HSC from AML xenografts experienced a loss of protein synthesis (OPP assay). We next reasoned that deficits in ribosome dysfunction and protein synthesis may reflect deregulation by specific miRNAs highly abundant in AML EV. Here, we had an opportunity to profile EV miRNA from the plasma of 12 unselected AML patients at diagnosis versus 12 control samples, and we confirmed a significant enrichment for specific miRNAs, including miR-1246. Raptor is a component of the mTOR pathway and an annotated target of miR-1246. We demonstrated in a series of experiments that miR-1246 translationally suppresses Raptor and downregulates protein synthesis in residual HSC from AML xenografts. The transfection of synthetic anti-miR1246 sequences on the other hand reversed the effects of AML EV in murine HSC. In aggregate we show that direct crosstalk between AML and hematopoietic cells adds to the adaptive changes that occur in the AML niche. Our experiments suggest a functional significance for EV miRNA that can be detected in AML patient plasma in the regulation of residual BM HSC. More broadly, the mechanisms by which leukemic stress alters hematopoietic function remain underexplored, but our observations suggest that leukemia derived EV contribute to changes in competitive fitness of residual HSC. Disclosures No relevant conflicts of interest to declare.

Diagnostic Dilemma of Epithelial Signet Ring Cells in Calculous Cholecystitis

Abstract Classic neoplastic signet ring cells are characterized by peripheral nuclear displacement by accumulation of cytoplasmic mucin in some adenocarcinomas. However, epithelial nonneoplastic signet ring cells may accumulate in the setting of mucosal erosion and ischemia as a reactive change of damaged columnar mucosa. Nonneoplastic signet ring cells may also occur as part of an inflammatory reaction due to histiocytes with signet-ring cell mucicarminophilia. A 58-year-old female presented with a 3-day history of increasing right upper quadrant abdominal pain. MRI showed distended gallbladder with 2 large stones, thickening of the gallbladder wall, and pericholecystic edema, consistent with acute cholecystitis. Laparoscopic cholecystectomy revealed a 15 × 6.0 × 3.5-cm gallbladder with eroded fundic mucosa, marked wall thickening (2 cm), and two intraluminal yellow stones, measuring 2.5 cm and 2.2. cm in diameter, respectively. The differential diagnosis included incidental gallbladder adenocarcinoma. Clusters of signet ring cells were seen in the fibrinous debris and were focally present in the superficial lamina propria. Intestinal metaplasia but no dysplasia was also observed. Loose clusters of pancytokeratin-positive, CD68-negative signet ring cells contained intracytoplasmic mucicarmine-positive mucin. Negative p53, low Ki-67, and positive E-cadherin supported the diagnosis of reactive signet ring cells. Deeply infiltrating pancytokeratin-positive epithelial cells were not identified. Final diagnosis was acute and chronic calculous cholecystitis with mucosal erosion and reactive signet ring cell epithelial change. Nonneoplastic epithelial signet ring cells may represent a diagnostic pitfall in chronically inflamed and eroded columnar cell mucosa of the gallbladder. A panel of immunostains and evaluation for cytologic atypia and unequivocal invasion are most helpful in differentiating this unusual reactive epithelial change, which occurs in response to inflammation, erosion, and/or ischemia, from signet ring cell carcinoma.

Peripheral hypervascularity of the corpus luteum with ovarian edema (CLOE) may decrease false positive diagnoses of ovarian torsion.

In patients with pelvic pain, corpus luteum with associated ovarian edema (CLOE) may be mistaken for ovarian torsion on ultrasound or CECT. This was a multi-reader, blinded, retrospective review performed at a single academic center from 2012 to 2018. Cases of CLOE that were misdiagnosed as torsion and cases of ovarian torsion without a lead-point mass were analyzed. Evaluated ultrasound features included presence of a corpus luteum, ovarian and corpus luteum volume, Color Doppler vascularity of the corpus luteum rim compared to that of the ovarian stroma, peripheral follicular displacement, twisted vascular pedicle, and free fluid. Evaluated CT features included presence of a corpus luteum, ovarian and corpus luteum volume, corpus luteum rim enhancement, twisted vascular pedicle, and free fluid. 39 cases of CLOE and 30 cases of ovarian torsion without lead-point mass were reviewed. A corpus luteum was present in 56.7% of torsed ovaries. In CLOE cases, peripheral hypervascularity of the corpus luteum (manifested as enhancement at CECT or flow signal at Doppler US) was present in 67.7% (21/31) of cases on ultrasound, and in 95.7% (22/23) of cases on CT. No peripheral hypervascularity of the corpus luteum was seen in cases of torsion (p < 0.001). Torsed ovaries were significantly larger than CLOE cases. Other findings were not significantly different between the two groups. Increased blood flow in the periphery of a corpus luteum on color Doppler ultrasound or on CECT is a strong negative predictor for ovarian torsion.

Stress Field Distribution and Deformation Law of Large Deformation Tunnel Excavation in Soft Rock Mass

The problem of large deformation is very prominent in deep-buried tunnel excavation in soft rock, which brings serious potential safety hazards and economic losses to projects. Knowledge of the stress field distribution and deformation law is the key to ensuring rational design and safe construction in large deformation tunnels of soft rock. As described in this paper, theoretical analysis, numerical simulation and field monitoring were employed to investigate the surrounding rock stress and displacement state in the Dongsong hydropower station in Sichuan Province, China. The results show that the short-bench construction method can effectively control the deformation of surrounding rock and range of the plastic zone. In order to reserve enough working space, the optimum bench length in the actual construction was 10 to 14 m. The peripheral displacement and plastic radius decreased with the increase of tunnel support strength and the advance of supporting time. The displacement can be effectively controlled by applying the second lining in time at a position about twice the diameter of the hole (16 m) from the working face. A reasonable reserved deformation should be adopted to avoid secondary expanding excavation. The values of different positions in the tunnel laterally and longitudinally may be different, and adjustments are needed according to the actual situation.

A case of massive ovarian edema: ovarian wedge resection by laparoendoscopic single-site surgery (LESS) resulted in complete remission of hyperandrogenic symptoms

Massive ovarian edema is a rare entity and easily mistaken as a malignant neoplasm of ovary. This pseudo-tumor occurs predominantly in young women and its presentation varies from being asymptomatic and to being a cause of acute abdomen, such as ovarian torsion. Polycystic ovary syndrome (PCOS) is characterized by elevated androgen and its pathogenesis is associated with endocrine dysfunction. Here the authors present a young woman who showed typical symptoms and signs of PCOS that was finally diagnosed to have massive ovarian edema by laparoendoscopic single-site surgery (LESS) and disappearance of the symptoms of PCOS after resection of edematous pseudo-tumor. This correlation is thought to be the removal of ovarian edema including large proportion of theca tissue which is responsible for overproduction of androgen in ovarian follicles. A 23-year-old woman, a registered nurse at this facility, visited the gynecologic department complaining of six-month amenorrhea and male pattern pubic hair growth. Initial transvaginal ultrasonography showed polycystic morphology in the left ovary and a large right adnexal solid mass with positive Doppler flows. Magnetic resonance imaging was performed and it revealed enlargement of right ovary measuring 9.3 centimeters in largest diameter, with peripheral displacement of follicles and massive ovarian edema was assumed to be a diagnosis. Operation for confirming diagnosis was decided after discussion with patient, as she was anxious for the uncertainty of the nature of the mass. Frozen section pathology report of right ovarian biopsy suggested cystic follicles with edematous stroma. Operation was ended after resection of the two-thirds of the right ovary that showed marked edematous change, while preserving one-third for future fertility. Final pathology confirmed the frozen biopsy. Her symptoms of PCOS that included irregular menstruation and male pattern pubic hair growth were completely improved after the surgery at six-month follow-up.

Mathematical modeling of belt and rigid conveyer’s drum contact with non-affect Coulomb friction

Conveyor’s belt with the drum contact task is paid a great researcher attention. It had solved in stresses with the mix boundary condition and Coulomb friction low action applies. Obtained solutions, as usual, do not satisfy to the displacement on drum surface boundary condition. The attempt to solve the system of Lamb equations in cylindrical coordinates in condition h/R&lt;&lt;1 values where h the belt thin and R drums radius is done. The Prandtl‘s technique and substitution methods are used to analytical solution obtain. As a result, the displacement expressions for rest and slide drum arcs are obtained. In search of rest arc length, radial and peripheral displacement equalities are used. Applied rest arc efforts are equal in values and have an opposite direction. The equality means the fact that traction efforts do not transfer under rest drum arc. The obtained results are coincided with the ones obtained by Zhukovskiy N.E. for flexible thread model. The fact to simultaneously satisfy to boundary conditions on inner and outer belt sides have to do the conclusion for boundary belt seam existing. Expressions for rest drum arc length without applied friction law are obtained. The displacement and corresponding stresses graphics are demonstrated.

Laboratory investigation on the buckling restrained braces with an optimal percentage of microstructure, polypropylene and hybrid fibers under cyclic loads

Normal braces have a high stiffness but are buckling under compressive strength and have very low ductility. To overcome these disadvantages in recent years, a buckling restrained braces system has been used. In this study the optimal percentage of Microstructure, Polypropylene and Hybrid Fibers were determined by using tensile and compressive test, the results exhibited that the highest rate of tensile and compressive strength were occurred in the case of reinforced concrete with polypropylene fibers and the composition of polypropylene and metal fibers as known hybrid fibers compared to the non-fibrous concrete for test specimens containing (0.15–0.3) percent polypropylene fiber and reinforced concrete with the composition of polypropylene and sinusoidal fibers related to test specimens containing (1.5%) metal fibers. Also, the results of scanning electron microscope imaging of concrete core sheaths obtained from fiber concrete in this study showed that fibers play a micro role in concrete. In addition, this research the effect of using optimum amount of fibers in the concrete sheaths in the buckling restrained braces were investigated. For this purpose, 6 samples of buckling restrained braces were made and examined in three modes. Concrete sheaths of buckling restrained braces without fibers, with polypropylene fibers and composition of polypropylene and sinusoidal metal fibers were the three modes. The samples made were then shifted to the intended location and installed in the laboratory under the loading protocol of BD/SAC – 02/97, also by applying the horizontal displacement contained in this protocol, the applied load and the amount of related peripheral displacement were calculated. Backbone, loading cycle-force, horizontal displacement – lateral displacement, push over curve and bilinear behavior model were finally drawn. By examining the results, it is shown that the maximum number of loading cycles, the coefficient of ductility, the energy absorption, and the maximum amount of applied force in the specimen produced by the composition of polypropylene and sinusoidal metal fibers are accrued.

盛土周辺地盤への変位抑制効果に着目した地盤改良について

盛土周辺地盤への変位抑制効果に着目した地盤改良について

Hepatic Lipidosis in Banded Armadillos (Euphractus sexcinctus) Bred in Captivity

Background: Wild animals bred in captivity may develop steatosis due to unbalanced dietary intake and obesity caused by sedentary behaviour. In some rural areas, six-banded armadillos are raised in captivity inside some metal barrels, with restricted space, and are often overfeed. After getting fattening, armadillos they are slaughtered and used as food. Theunfavorable conditions may somehow contribute to likely underlie the development of many diseases, among them we can including hepatic steatosis. The present report aims to describe the pathological fndings of hepatic lipidosis in banded armadillos (Euphractus sexcinctus), bred in captivity.Case: The animals were three female adult six-banded armadillos (Euphractus sexcinctus), caught in the native forest of the city of Natal, Rio Grande do Norte, Brazil and raised in domestic environment in a small enclosure and fed with human food leftovers. After eight months kept in these conditions armadillos had severe obesity and then were donated to the city zoo, where they were quarantined and presented clinical symptoms of anorexia for two weeks, weight loss and exhaustion. After being found dead during daily inspection carried out by the veterinarian zoo, the six-banded armadillos were sent to the Animal Pathology Laboratory of Federal Rural University of the Semi-Arid (UFERSA) for pathological examination.The animals presented with a history of anorexia were extremely obese and the autopsy detected had extensive deposits of fat in the carcass and liver. Histopathologically, the liver cells hepatocytes showed marked intracytoplasmic vacuolization and with peripheral displacement of the nucleus to the periphery, with and positive staining for lipids using scarlet Sudan III. To our knowledge, this is the frst report of hepatic lipidosis in banded.Discussion: Hepatic lipidosis can be categorized into normal liver and mild, moderate, or severe fatty liver. In severe cases, it is estimated that 80% of the hepatocytes are affected. Therefore, we classifed the hepatic lipidosis of the three studied female six-banded armadillos as severe, since the lipids were deposited diffusely. Based on the severity of the lesions and absence of other fndings, we concluded here that hepatic lipidosis contributed to the cause of the six-banded armadil los death. The weight of the animals in this report may be associated with innapropriate enclosure dimensions and a diet based on human food leftovers. Such diet was reportedly composed of rice, beens, spaghetti, and bread, which are food with high levels of carbohydrate. The armadillos of the Euphractus sexcinctus species usually weigh between 3 and 6 kg and hence, the animals of this report showed twice the normal weight. The occurrence of hepatic lipidosis associated with anorexia triggered by a stressful event such as a change of environment and diet armadillos observed in the present study is in agreement with literature data pointing anorexia in obese animals as a major predisposing factors for the occurrence of hepatic lipidosis by promoting energy restriction, peripheral lipolysis and large intake of fatty acids to the liver.Keywords: Euphractus sexcinctus, armadillos, anatomopathology, liver, lipidosis.

Effect of acute systemic hypoxia on human cutaneous microcirculation and endothelial, sympathetic and myogenic activity

The regulation of cutaneous vascular tone impacts vascular vasomotion and blood volume distribution as a challenge to hypoxia, but the regulatory mechanisms yet remain poorly understood. A skin has a very compliant circulation, an increase in skin blood flow results in large peripheral displacement of blood volume, which could be controlled by local and systemic regulatory factors. The aim of this study was to determine the acute systemic hypoxia influence on blood flow in skin, local regulatory mechanism fluctuations and changes of systemic hemodynamic parameters. Healthy subjects (n=11; 24.9±3.7years old) participated in this study and procedures were performed in siting position. After 20min of acclimatization 15min of basal resting period in normoxia (pO2=21%) was recorded, followed by 20min in acute systemic hypoxia (pO2=12%), and after 15min of recovery period in normoxia (pO2=21%). HRV was used to evaluate autonomic nervous system activity to heart from systemic hemodynamic parameters which continuously evaluated cardiac output, total peripheral resistance and mean arterial blood pressure. Regional blood flow was evaluated by venous occlusion plethysmography and skin blood flow by laser-Doppler flowmetry. To evaluate local factor influences to cutaneous circulation wavelet analysis was used; fluctuations in the frequency intervals of 0.0095–0.021, 0.021–0.052, and 0.052–0.145Hz correspondingly represent endothelial, sympathetic, and myogenic activities. Our results from HRV data suggest that acute systemic hypoxia causes statistically significant increase of sympathetic (LF/HF; N1=0.46±0.25 vs. H=0.67±0.36; P=0.027) and decrease of parasympathetic (RMSSD; 80.0±43.1 vs. H=69.9±40.4, ms; P=0.009) outflow to heart. Acute hypoxia causes statistically significant increase of heart rate (RR interval; N1=960.3±174.5 vs. H=864.7±134.6, ms; P=0.001) and cardiac output (CO; N1=5.4 (5.2; 7.9) vs. H=6.7±1.4, l/min; P=0.020). Regional blood flow and vascular conductance were not changed during acute systemic hypoxia, but forearm skin blood flow (skin blood flow; N1=39.7 (34.0; 53.2) vs. H=51.6±13.9, PU; P=0.002) increases however local regulatory factor activity was not changed by acute systemic hypoxia. Acute systemic hypoxia causes sympathetic stimulation to heart which results in increased heart rate and larger cardiac output which could be the reason of forearm skin blood flow increase in acute systemic hypoxia without impact of local regulatory factors.

Influence of stress path on excavation unloading response

The unloading process of rock mass is critical to the research of excavation disturbances of tunnels in deep mines, and the dynamic effects induced by the release of in situ stress cannot be ignored. In this study, a mathematical physics model was applied to characterise the unloading mechanisms of brittle rock under different stress paths in two dimensions using the universal discrete element code PFC2D for numerical simulations. The excavation relaxation method was employed to control forces applied to the tunnel internal surface to investigate the influence of various in situ stresses, the unloading rate and path on the dynamic effects. Longer unloading time can mitigate the dynamic effects within a certain time range. Nonlinear unloading paths prevail over the linear path in releasing kinetic energy. Furthermore, the exponential path that represents “slow followed by fast” unloading induces the most peripheral displacement, while the cosine path that represents “fast followed by slow” unloading yields the most cracks around the tunnel. The results also indicated that increasing the ratio of horizontal and vertical in situ stresses can exacerbate the dynamic effects. The proposed model agreed well with the theoretical solution and provided a basis for understanding the evolution of the unloading response around the tunnel.

Sagging Eye Syndrome

Recognition of sagging eye syndrome (SES) as the cause of chronic or acute acquired diplopia may avert neurologic evaluation and imaging in most cases. To determine whether SES results from inferior shift of lateral rectus (LR) extraocular muscle (EOM) pulleys and to investigate anatomic correlates of strabismus in SES. We used magnetic resonance imaging to evaluate rectus EOMs, pulleys, and the LR-superior rectus (SR) band ligament at an eye institute. Patients with acquired diplopia suspected of having SES. We studied 56 orbits of 11 men and 17 women (mean [SD] age of 69.4 [11.9] years) clinically diagnosed with SES. Data were obtained from 25 orbits of 14 control participants age-matched to SES and from 52 orbits of 28 younger controls (23 [4.6] years). Rectus pulley locations compared with age-matched norms and lengths of the LR-SR band ligament and rectus EOMs. Data were correlated with facial features, binocular alignment, and fundus torsion. Patients with SES commonly exhibited blepharoptosis and superior sulcus defect. Significant inferolateral LR pulley displacement was confirmed in SES, but the spectrum of abnormalities was extended to peripheral displacement of all other rectus pulleys and lateral displacement of the inferior rectus pulley, with elongation of rectus EOMs (P < .001). Symmetrical LR sag was associated with divergence paralysis esotropia and asymmetrical LR sag greater than 1 mm with cyclovertical strabismus. The LR-SR band was ruptured in 91% of patients with SES. Widespread rectus pulley displacement and EOM elongation, associated with LR-SR band rupture, causes acquired vertical and horizontal strabismus. Small-angle esotropia or hypertropia may result from common involutional changes in EOMs and orbital connective tissues that may be suspected from features evident on external examination.