Narrow Neck Research Articles

Age Related Trends in Structural Indices of Proximal Femur in Women Aged 20-70 in Southern Sri Lanka

Age related trends of the indices of hip structure help understanding how bone strength changes with age and the increased bone fragility in old age. Community-dwelling women aged 20-70years (n = 419) were selected by stratified random method and divided into age categories; 20-29years (n-69), 30-39years (n = 60), 40-49years (n = 69), 50-59years (n = 107) and 60-70years (n = 114). All subjects underwent dual energy x-ray absorptiometry (DXA) and hip structure analysis using Hologic Discovery scanner (Hologic Inc, Bedford, USA). Measured indices included hip axis length (HAL) and neck shaft angle (NSA) of the proximal femur. Cross sectional area (CSA), cross sectional moment of inertia (CSMI), section modulus (SM), cortical thickness (CT), buckling ration (BR) of three regions of interest; narrow neck, intertrochanteric region and femoral shaft, were also measured. Age related trends of all indices were studied with Locally Weighted Scatterplot Smoothing lines (LOESS) and ANOVA. Mean HAL and NSA values were not different between age categories. CSA, CSMI, SM and CT in three different regions showed curvilinear relationships with age. These indices gradually increased with age between 20-50 years and the maximum values were seen in the 40-49years age category and they declined afterwards. The decline of these indices was more rapid in the narrow neck and intertrochanter regions when compared with femoral shaft and the lowest mean CSA, CSMI, SM and CT in these two regions were seen in the 60-70 age category. BR showed a gradual decrease with age between 20-50 years and the lowest mean value was seen in the 40-49 age category. BR increased afterwards and the maximum mean value was seen in the 60-70 age category. This study demonstrates the dynamics of structural properties of proximal femur in the three selected cross sections of community-dwelling women aged 20-70 years and the increased bone fragility in old age.

Comparative larval ultramorphology of three endemic Lathrobium (Glyptomerus) species (Coleoptera, Staphylinidae, Paederinae) from the Eastern Alps in Italy.

The paper describes the mature larvae (L2) of Lathrobium alzonai, L. freyi and L. paceiendemic, depigmented, apterous and subanophthalmous rove beetles from the Eastern Alps in Italy (Coleoptera: Staphylinidae; Paederine)belonging to the subgenus Glyptomerus. The larva of Lathrobium pacei Piva, 1994 is described for the first time, whereas the larvae of L. alzonai Capra Binaghi, 1938 and L. freyi Koch, 1938 are redescribed. Detailed illustrations of their structural features are provided, and diagnostic larval - morphological characters for Lathrobium are proposed. Based on earlier published and new data, morphological comparisons, both intergeneric (between Lathrobium and Tetartopeus) and interspecific (between L. alzonai, L. freyi and L. pacei) within the subtribe Lathrobiina, are made. The principal differences among the genera and species involve particular structures of the head and their measurements. The generic status of Tetartopeus was confirmed. No clear differences in the external morphological structure between the larvae of Glyptomerus and Lathrobium s.str. were noted. The morphological structure of L. alzonai larvae differed significantly from that of the larvae of the other two species. The differences relate mainly to the much larger body size of L. alzonai, the shape of the head with its relatively narrow neck, the details of the mouthparts structure and the distinct elongation of its antennae, maxillary palps, labial palps, some parts of the legs and urogomphi. Distribution of all known Italian glyptomeroid species of the genus Lathrobium is also given.

First Report of Anthracnose Disease on avocado (Persea americana) caused by Colletotrichum fructicola in China.

In September 2019, anthracnose-like symptoms were observed on fresh avocado fruits cv. "Hass", which were imported from Peru (Mission Produce, Inc.) and purchased at Ganfuyuan store, Guangzhou, China. After being stored for 5 days at room temperature, initial black specks developed into larger brown or black lesions on fruits, and salmon-colored conidial mass in the lesions were observed. To isolate and identify the pathogen, small pieces (5 mm × 5 mm) were excised from the lesion margins of the fruits, which were surface sterilized by 1% NaOCl (1 min), 70% ethanol (30 s) and then washed twice with sterile distilled water (SDW). After sterilization, the tissues were cultured on Potato Dextrose Agar (PDA) to obtain the pure strain NYG. The colonies grown on PDA for 7 days appeared to be cottony, white to pale gray with the presence of a conidial mass. Conidia 11.7-19 × 3.6-6.4 μm (n = 50), hyaline, aseptate, straight and cylindrical with rounded ends, Appressoria 6.2-11.9 × 4.5 × 7.4 μm (n = 50), brown to dark brown in different shapes. Perithecia were thick-walled and globose with a prominent, narrow neck. Asci 31.5-55 × 6-12.5 μm (n = 15), 6-8 spored, clavate to cymbiform. Ascospores 5-18 × 4.5-6 μm (n = 25), hyaline, large guttulate at the centre, slightly curved, rounded ends. Based on the morphological characteristics, the strain NYG was identified as Colletotrichum fructicola (Prihastuti et al. 2009). The identity of the strain was confirmed by means of multi-locus gene sequencing. The genomic DNA was extracted using Ezup Column Fungi Genomic DNA Purification Kit (Sangon Biotech Co., Ltd., China). The internal transcribed spacer (ITS) rDNA region, actin (ACT), chitin synthase (CHS-1), calmodulin (CAL), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) partial genes (Templeton et al. 1999, Carbone et al. 1999) were amplified and sequenced, which were deposited in GenBank (OL413493, OL517766, OL517768, OM141126, OL517767). BLASTN analysis revealed that DNA sequences of the isolate showed 100% identity with those of C. fructicola (MT476840.1, MK208862.1, MZ965245.1, JX009665.1, MN982434.1), respectively. A phylogenetic tree analysis based on the concatenated sequences confirmed the isolate as C. fructicola. Pathogenicity was tested by infecting the fresh healthy avocado fruits with the isolated strain NYG. The fruits were surface sterilized, three unwounded and wounded avocados fruits were respectively inoculated with 10 l of conidial suspension (1×106 conidia/ml) by the drop inoculation method. Control fruits were inoculated with SDW containing Tween 20 (1 μl/ml H2O), respectively. All inoculated fruits were incubated at 25°C in the dark. Anthracnose symptoms were observed on the wounded and unwounded fruits after 3 to 5 days post inoculation, respectively. No symptoms were observed in the control on both the wounded and unwounded fruits. The pathogenicity test was performed in duplicate. The inoculated fungus was reisolated from the infected fruits and confirmed as C. fructicola, thus confirming Koch's postulates. C. fructicola represents an important fungal pathogen in several plantations worldwide (Farr et al. 2020), for example, the avocado fruits in Mexico (Dionicio, et al. 2018) and New Zealand (Hofer et al. 2021). This is the first report of anthracnose caused by C. fructicola on imported avocado fruits in China. The results of this study can not only help establish effective quarantine measures against anthracnose disease for imported avocado fruits in China, but also provide important reference to prevent the spread of this disease on China's domestic avocados.

Infrarenal EVAR for Penetrating Aortic Ulcer: A Comparative Study with Abdominal Aortic Aneurysm

Endovascular aortic repair (EVAR), currently the preferred treatment for abdominal aortic aneurysm (AAA), has been described also for penetrating aortic ulcers (PAU) of the infrarenal aorta. However, data on its performance in this particular setting are still sparse in the literature. Aim of this study is to compare patient clinical characteristics, aorto-iliac features, and post-operative outcomes between infrarenal PAU and AAA treated by standard EVAR. In this retrospective observational case-control multicenter study, the patients treated for infrarenal PAU (G1) with EVAR in 2 high-volume European centers from January 2014 to December 2019 were prospectively entered into a dedicated database and retrospectively analyzed. A 4-fold control group (G2) of infrarenal AAA patients, homogeneous for age and gender, was also considered. Preoperative clinical characteristics, aorto-iliac features (rupture, aortic maximum diameter, proximal neck diameter and length, aortic bifurcation diameter, distance between the lowest renal artery and the aortic bifurcation [RA-AoBi], severe aortic calcification), technical success, 30-day (morbidity, reintervention, complications, mortality) and follow-up outcomes (freedom from reintervention [FFR] and survival) were compared in the 2 groups (chi square/Fisher exact test, t-student test, Mann-Whitney test, logistic regression and Kaplan-Meier analysis). Seventy-three patients (age 78±7years; male 84.9%) were included in G1 and 299 (age 78.4±6.6years; male 89.3%) in G2. At the time of diagnosis, G1 patients were more often symptomatic compared with G2 (odds ratio OR 10.21, 95% confidence interval CI 4.17-24.99, P<0.001). At preoperative computed tomography angiography, G1 patients had more ruptures (OR 8.11, 95% CI 3.50-18.78, P<0.001), smaller maximum diameter (OR 1.05, 95% CI 1.03-1.08, P<0.001), longer and narrower proximal neck (OR 0.97, 95% CI 0.95-0.99, P=0.020 and OR 1.47, 95% CI 1.32-1.64, P<0.001, respectively) narrower aortic bifurcation (OR 1.34, 95% CI 1.24-1.45, P<0.001), lower RA-AoBi (OR 1.09, 95% CI 1.07-1.12, P<0.001), and more severe aortic calcification (OR 57, 95% CI 16-198, P=0.001). Technical success (G1 98.6% vs G2 95.7% P=0.320), 30-day morbidity (G1 2.7% vs G2 8.7% P=0.133), reintervention (G1 2.7% vs G2 2.3% P=0.691), complications (G1 6.8% vs G2 8% P=0.737) and mortality (G1 1.4% vs 2% P=0.720) were comparable in the 2 groups. The mean follow-up was 17.7±16.4months in G1 and 18.8±15.1 in G2 (P=0.576). Late FFR and survival were comparable in the 2 groups (1-year FFR: G1 94.8% vs G2 97.5%, P=0.995; 1-year survival: G1 91.7% vs G2 92.3%, P=0.960). Infrarenal PAU are more often symptomatic with a higher rupture rate compared to infrarenal AAA. Despite some negative anatomical characteristics (narrower aortic bifurcation, lower RA-AoBi, extensive calcification), the results of EVAR are extremely satisfactory in this setting, suggesting that endovascular exclusion could be considered a valid treatment for infrarenal PAU.

Morphological and Phylogenetic Characterization Reveals Five New Species of Samsoniella (Cordycipitaceae, Hypocreales).

Samsoniella is a very important fungal resource, with some species in the genus having great medical, economic and ecological value. This study reports five new species of Samsoniella from Yunnan Province and Guizhou Province in Southwestern China and Dole Province in Vietnam, providing morphological descriptions, illustrations, phylogenetic placements, associated hosts and comparisons with allied taxa. Based on morphological observations and phylogenetic analyses of combined nrSSU, nrLSU, tef-1α, rpb1 and rpb2 sequence data, it was determined that these five new species were located in the clade of Samsoniella and different from other species of Samsoniella. The five novel species had morphologies similar to those of other species in the genus, with bright orange cylindrical to clavate stromata (gregarious). The fertile part lateral sides usually had a longitudinal ditch without producing perithecia, and superficial perithecia. The phialides had a swollen basal portion, tapering abruptly into a narrow neck and oval or fusiform one-celled conidia, often in chains. The morphological characteristics of 23 species in Samsoniella, including five novel species and 18 known taxa, were also compared in the present study.

Cation exchange capacity and soil pore system play key roles in water vapour sorption

Understanding the controlling factors of soil water vapour sorption at different water activities (aw) is essential for accurate estimation of soil properties, such as cation exchange capacity (CEC) and specific surface area (SSA). The objective of this study was to identify the role of CEC and soil pore system in water vapour sorption and sorption hysteresis over a range of aw values. The CEC, SSA, pore volume, and water and nitrogen adsorption/desorption isotherms for eight soils with different clay contents and mineralogies were measured. Irrespective of aw and sorption direction, there was a significant correlation between water content and CEC, and the correlation varied with aw. The water content change was mainly related to CEC and SSAH2O for aw < ∼0.6, and to SSAN2 and pore volume for aw > ∼0.6. Similar to the forced closure phenomenon of the soil nitrogen desorption branch at a relative pressure (P/P0) of ∼ 0.45, the soil water vapour desorption branch also exhibited a sudden drop in the range of 0.2 < aw < 0.4. The water vapour sorption hysteresis for aw < ∼0.75 was mainly due to the difference in cation hydration during the adsorption and desorption process, and the hysteresis phenomena for aw > ∼0.75 was attributed to the different sizes of narrow pore necks and the connected pores.

Spacing and strain during multiphase boudinage in 3D

Most models of brittle boudinage predict a dependency of fracture spacing on thickness of the boudinaged layer. This basic relationship can be distorted in the case of multiphase boudinage, where structural inheritance, possibly combined with time evolution of rheology affects boudin geometries, but is not recognized in 2D outcrops. Here we present analyses from a metre-scale, serially sectioned sample of marble from Naxos, Greece, containing a layer of amphibolite, which is known to have experienced two phases of ductile drawn boudinage followed by five generations of brittle boudinage. We show that brittle boudinage depends on the ratio of grain size and layer thickness of the amphibolite. In very thin layers (few grains across), strain is diffuse throughout the entire layer, leading to macroscopically homogeneous stretching. Strain localisation starts when layer thickness exceeds 5 grains: narrow tensile necks and shear zones (35–45° dip) develop where the layer is < 10–20 grains thick. Thicker layers (<30–40 grains) show extensional (mode 1) fractures while shear fractures form in even thicker layers. The absence of shear fractures in thinner layers may be explained by a geometry-related compressive stress decrease in the pinches. This results in localised shear evolving only in thicker layers. Complete delocalisation where layer thickness approaches the grain scale is expected as the typical shear bandwidth in granular media (10–20 grains) exceeds layer thickness. Successive fracture reactivation causes geometrical complexity in the form of splays and branches, and in addition the thickness-dependence of strain localisation governs fracture distribution in the layer. A second, temporal trend is recorded in the progressive embrittlement of the rocks as they cooled during exhumation, evidenced by increasing fracture density and a switch from shear to extensional fracturing. In the final stages, the marble was brittle enough to allow fracture propagation from the amphibolite across the material interface into the marble and, finally, the formation of brittle fractures affecting both the amphibolite and marble.

P130 A RARE CASE OF LARGE POST INFARCTION LEFT VENTRICULAR PSEUDOANEURYSM UNDERGOING CONSERVATIVE MANAGEMENT

Abstract Introduction Left ventricular pseudoaneurysm is a rare complication of myocardial infarction and its natural history is still unclear. Non invasive imaging improves detection ability and differential diagnosis with aneurysm. We present the case of large post infarction left ventricular pseudoaneurysm undergoing conservative management. Case Report A 81–years–old woman presented to emergency room complaining dyspnea and epigastric and right hemithoracic pain. Her past medical history included: chronic coronary syndrome, already undergoing CABG; recent inferior STEMI complicated with complete AVB, with ineffective RCA reperfusion attempt and bicameral pacemaker implantation; Paroxysmal AF in antithrombotic prophylaxis with DOAC. The ECG showed sinus tachycardia, HR 114 bpm, electro–induced ventricular complexes. Objectively, fine bilateral basal crackles were detected. Chest x–ray showed pulmonary congestion. The echocardiographic examination revealed: left ventricle with eccentric remodeling and severe depression of the contractile function (EF 35%), coarse neochamber in communication with the basal segment of the lower wall (D: 6.4 cm x 4.9 cm). The narrow neck, with a ratio &amp;lt;0.5 between inlet orifice diameter / neochamber diameter, suggested pseudoaneurysm. Working diagnosis of NSTEMI–ACS was made (usTnT peak: 344 pg / mL, NV: 0–15 pg / mL) complicated by heart failure. Progressive improvement in compensation was achieved through diuretic therapy. To improve diagnostic definition, cardio–synchronized chest CT with contrast medium was performed. The examination confirmed the voluminous neochamber, consistent with pseudoaneurysm, in correspondence with the mid–basal segments of the lower and inferior septal wall, with thinned walls and mass effect on the great cardiac vein, and highlighted the patency of the bypasses. The venous graft to OM was 5 mm distant from the posterior sternal surface. The case was discussed collectively in Heart Team, due to the high operative risk, the surgical option was rejected and a decision was made for conservative therapy. It was titled beta–blocker, ranolazine was introduced, heart failure therapy was implemented, introducing ARNI. The patient was discharged at home and is in follow–up at the outpatient clinic for heart failure. One month after discharge, she is in NYHA functional class II and she is asymptomatic for angor. The pseudoaneurysmatic dimensions are unchanged on echocardiographic control.

Musculoskeletal Differences Between Amputated and Non‐Amputated Lower Limbs

People with lower limb amputations frequently experience greater risks of musculoskeletal injury. Forces active during walking help to develop and maintain the shape, volume, and strength of musculoskeletal tissues. Conversely, altered walking patterns following limb loss may lead to atrophy of muscle and bone tissues. Reductions in joint spaces are indicative of excess stress placed on the limb, which may lead to osteoarthritis. Bone loss in high stress regions like the femoral neck can reduce the bone’s ability to resist compressive or rotational movements, making the bone more susceptible to fracture.The aim of this study was to measure musculoskeletal differences between an individual's residual (amputated) limb and intact (non‐amputated) limb to identify structures vulnerable to injury. We hypothesized that the residual limb, compared to the intact limb, would show: 1) less muscle mass and more fat as indicators of muscle atrophy, 2) wider hip and knee joint spaces as indicators of osteoarthritis in the intact limb, and 3) decreased femoral neck width as an indicator of fracture risk.CT scans of 10 males (42‐79 years) were obtained from the New Mexico Decedent Image Database. 3D Slicer software was used to measure gross skeletal properties, hip and knee joint dimensions, and cross‐sectional muscle and fat tissue areas at the midshaft. A Wilcoxon Signed‐Rank test was used to assess the differences between residual and intact limbs. The significance level was set at α ≤ 0.10 due to a small sample size. Compared to the intact limb, the residual limb had significantly less muscle tissue area (p=0.010) and a significantly narrower femoral neck width (p=0.077). No significant differences were found in hip or knee joint spaces between limbs.In agreement with hypotheses 1 and 3, these results suggest residual limbs are at increased risk of muscle atrophy and femoral neck fracture compared to intact limbs. Loading inequalities between the residual and intact limb likely contribute to these results. A better understanding of the structural properties associated with musculoskeletal atrophy could inform targeted therapies to reduce the likelihood of injury in this population. Future studies will assess biomechanical properties, such as moment of inertia, to better understand the residual limb’s ability to withstand torsional forces and fracture. Additional data on how musculoskeletal tissues respond to unloading at multiple structural levels can improve clinical interventions for lower limb strength and function in amputees.

Rare case report of strangulated spigelian hernia mimicking an abdominal mass

A Spigelian hernia, an infrequent occurrence, is an abdominal wall hernia that occurs through the Spigelian fascia, an aponeurotic sheet located medially by rectus muscles and laterally by the semilunar line. The hernial sac lies either deep to the internal oblique muscles or between the oblique muscles. A Spigelian hernia requires repair due to the risk of incarceration with its relatively narrow neck. The below case report provide shows a patient, who came with an abdominal mass that was diagnosed as a strangulated Spigelian hernia and managed with an emergency surgery.

New Insights Into the Development of the Anterior Abdominal Wall.

PurposeAmong the few studies that have examined the development of the anterior abdominal wall, several are based on incomplete “series”, substituted in many cases by non-human specimens.Material and MethodsIn total, 19 human embryos corresponding to Carnegie stages 15–23, 36 fetuses with estimated gestational ages ranging from 9 weeks to term, and eight neonates were included in this study. All specimens belong to the collection of the Department of Anatomy and Embryology at the Complutense University of Madrid.ResultsThe muscles of the anterior abdominal wall appear in the dorsal region at stages 15 and 16 (33–37 days). At stages 17 and 18 (41–44 days), this muscular mass grows ventrally and splits into two sheets: the external abdominal oblique muscle and the common mass of the internal abdominal oblique, and the transversus abdominis muscles, all of which end ventrally in the primitive condensation of the rectus abdominis. In embryos at stages 19 and 20 (48 days), the anterior abdominal wall continues to show an umbilical hernia in the amniotic cavity. However, a narrow neck is apparent for the first time and there is a wider anterior abdominal wall below the hernia made up of dense mesenchyme tissue without layers and showing the primordia of the umbilical canal. In embryos at stages 21, 22, and 23 (51–57 days), the abdominal muscles and aponeuroses cross the midline (linea alba) covering the rectus abdominis and pyramidalis muscles while the umbilical hernia has shrunk. In fetuses during the 9th and 10th weeks, the umbilical hernia becomes encircled by the rectus abdominis muscle, its aponeurosis, and the three layers of lateral abdominal muscles, which are more developed and covered by Camper's and Scarpa's fasciae. The inguinal canal has a course and relationships like those described in adults, with Hesselbach's ligament.

Subarachnoid hemorrhage due to rupture of very small aneurysms of the anterior part of the circle of Willis

Objective: To assess the frequency of ruptures of very small cerebral aneurysms, features of the perioperative period and outcomes, in comparison with the rupture of ordinarily sized aneurysms.Material and methods: A comparative analysis of the group of patients with ruptured cerebral miliary aneurysms (n = 18) and the group of patients with ruptured cerebral aneurysms of regular size (n = 308) was carried out. All patients underwent open surgery in the first 3 days after the rupture (osteoplastic craniotomy, microsurgical aneurysm clipping). We compared gender, age of patients, severity of the patient’s condition at the moment of admission, severity of subarachnoid hemorrhage, location of aneurysms, aspect ratio, duration of the operation, frequency of intraoperative ruptures, postoperative mortality.Results: It was found that miliary aneurysm rupture occurs in 5.5% of all patients with cerebral aneurysm rupture. The most common cases of rupture of very small aneurysms were in women (77.7%), with a mean age of 50.8 years. Aneurysms of the anterior communicating artery (66.6%) with a narrow neck (average aspect ratio – 2.1) were the most common. Patients with rupture of very small aneurysms were 7.9% more likely to be admitted in a state of subcompensation or decompensation (Hunt-Hess IV–V), they had massive subarachnoid hemorrhage (Fisher III) 19.6% more often than with ruptured aneurysms of regular size. On average, operations in cases of very small aneurysms lasted 30 minutes less than clipping of ordinary aneurysms, but were complicated by intraoperative rupture twice as often (38.8% and 16.5%, respectively). Postoperative mortality in the group of patients with ruptured miliary aneurysms was 5.7% higher than in patients with ruptured aneurysms of regular size.Conclusion: Rupture of cerebral miliary aneurysms is relatively rare. Women of 50–60 years old with very small aneurysms of the anterior communicating artery with a narrow neck constitute the main group of such patients. Massive subarachnoid hemorrhage and severe condition of patients on admission are more common with miliary aneurysms than with ordinarily sized aneurysms. The small size of the aneurysm and the work near the rupture determine the more frequent contact intraoperative rupture when the neck is exposed as compared to operations on larger aneurysms, which negatively affects the treatment outcomes in this group of patients.

GENERAL CHARACTERISTICS OF RENAL CALICES OF A MATURE AND ELDERLY HUMAN

The use of non-invasive and minimally invasive diagnostic and treatment methods in modern urological practice dictates the need to study the location of the initial section of the extrarenal urinary tract. The aim of the study was to describe general characteristics of renal calices of a mature and elderly human. Material and methods. The study included 175 corrosive preparations of human pyelocalyceal complexes. Organometric study of number, shape of arches, linear parameters, volumes, ranking place in the ranking distribution of renal calyces volumes was performed. Results. The upper renal is characterized by a large height (14.8±9.2 mm) and a wide neck (7.2±2.3 mm) and the largest volume 1202-1246 mm3. The anterior superior renal calyx has round vault of medium diameter (6.7±2.3 mm) and medium height (7.2±3.1 mm), a narrow neck (5.0±1.6 mm) and a small stable volume (14.8 mm3). The anterior middle calyx has a round vault of medium diameter (7.4±2.2 mm) and height (10.7±5.1 mm) and a narrow neck (4.8±1.6 mm); its volume is 348.4 mm3. The anterior inferior renal calyx has medium diameter (7.2±2.3 mm) and height (8.9±4.6 mm) with a narrow neck (4.8±1.8 mm); its volume is 275.2-307.1 mm3. The posterior superior renal calyx has medium arch diameter (8.4±3.0 mm) and height (8.6±4.5 mm) with a narrow neck (5.7±2.1 mm) and a small stable volume (less than 500.0 mm3). The posterior middle renal calyx has medium diameter (7.2±2.3 mm) and height (10.7±5.1 mm) with a narrow neck (5.1±1.9 mm), medium volume (402.1 mm3). The posterior inferior renal calyx has medium diameter (7.2±2.2 mm) and height (7.0±3.6 mm) with a narrow neck (5.3±2.3 mm), small stable volume (402.1 mm3). The lower renal calyx has medium diameter (7.4±2.4 mm) and height (8.6±4.6 mm) with a narrow neck (5.7±2.2 mm) and medium volume (402.1 mm3). Conclusions. As a result of the study, we determined the general characteristics of the renal calyces of a person of mature and elderly ages. New morphological information about the structure of the pyelocalyceal complex can be used to improve the diagnosis and treatment of the kidneys extrarenal urinary tract.

On-machine measurement and temperature compensation method of NURBS surface interpolation for semicircular narrow neck thickness based on ultra-precision machine tool

Flexible joint is a typical low-rigidity micro part, which has four narrow neck structures evenly distributed around its central axis. In the ultra-precision machining process, it is crucial to control the dimensional accuracy of the narrow necks to improve stiffness consistency. However, the limited space of the neck structures and the high accuracy requirements bring extremely difficulties to the measuring process. In this paper, a novel on-machine measurement method for the semicircular narrow necks was presented and a measuring device was developed based on the combination of high linearity incremental measurement method and on-machine measurement technology. Moreover, the uncertainty of measurement error was analyzed in detail. In view of the measurement error caused by temperature drift, a compensation method based on non-uniform rational B-spline surface interpolation was used to enhance the measurement accuracy. The experimental results showed that the measurement accuracy enhanced over 30% after compensation, which met the measuring requirement of flexible joint.

Experimental study on open-end correction of a Helmholtz resonator narrow slit neck

In general, the acoustic effective length of the open end of an air column is longer than its geometric length. Here, the effective increment of the geometric length of an air column is called the open-end correction length, which is an acoustically crucial issue. The purpose of this study is to experimentally clarify the open-end correction length for a slit shape with a narrow clearance. For this reason, the sound absorption coefficient was measured using a sample in which the neck of the Helmholtz resonator was shaped as a slit with a narrow clearance. Next, the open-end correction length (i.e., mass end correction length and resistive end correction length) was calculated backward by comparing the experimental and theoretical sound absorption curves. The resistive end correction increased as the slit width became narrower within the range of 0.5 mm or less for both the center slit and the slit near the wall, indicating a significant discrepancy between the theoretical equation and the estimated value. For the mass end correction, in the case the center slit, the estimated value is close to the theoretical value of in the slit width range from 0.3 mm to 1.0 mm. The results of this study may be useful in eliminating discrepancies in correction values for open-end correction in slits with narrow clearance.

Abstract 77: BMD, TBS and HSA in chronic glucocorticoid users attending a tertiary centre in Southern India

Background: Glucocorticoids (GC) are used for various chronic medical conditions and is one of the most abused drugs in India. Despite widespread GC use, there is lack of knowledge among physicians regarding assessment and management of glucocorticoid induced osteoporosis (GIO). This study was performed to assess bone mineral density (BMD), trabecular bone score (TBS) and hip structural analysis (HSA) in chronic steroid users.Methods: Observational study done from 2013-2020. Details of patients were obtained through archived medical records. Bone biochemical parameters and densitometric variables that included bone mineral density (BMD), trabecular bone score (TBS) and hip structural analysis (HSA) were assessed by a DXA scan.Results: A total of 74 subjects (56 females, 45/56 postmenopausal) with a mean (SD) age and BMI of 49.5 (12.5) years, 29.0 (6.9) kg/m2 were studied. Vitamin D deficiency was present in 33/74 (44.6%) of subjects. 15 subjects (20.3%) had sustained fragility fractures. At baseline, the prevalence of osteoporosis at NOF and lumbar spine was 24/74 (32.4%) and 34/74 (45.9%) respectively. Degraded trabecular microarchitecture as defined by a TBS <1.200 was present in 32/74 (43.2%) of the subjects. Among those with normal BMD at the lumbar spine, 13/40 (32.5%) had a low TBS. Buckling ratio (BR) at the narrow (NN) neck > 10 was seen in 57/74 (77%) of subjects. Among subjects with normal BMD at the femoral neck, 33/50 (66%) had a BR at NN >10, which indicates high fracture risk.Conclusion: GIO continues to be prevalent among steroid users. TBS and HSA may confer additional benefit regarding bone health, not conveyed by conventional BMD assessment in chronic glucocorticoid users.

Research of Feeding Effect of Ductile Cast Iron under Different Riser Conditions

Ductile cast iron has typical characteristics of mushy solidification and ductile expansion. The feeding effect of ductile cast iron was studied by means of numerical simulation and pouring tests. The prototypes used for experiments were designed into three types: riser without neck; riser with narrow neck; and riser-less. The corresponding molds were made of coated sand. The pouring temperature was set to 1350 °C, 1300 °C, and 1250 °C, separately. Results showed that the feeding effect could be controlled by the riser structure and the pouring temperature comprehensively. If the pouring temperature was higher than a certain value, the casting should be fed by a riser, and the riser structure would play an important role. However, it was very hard to design a riser exactly, and the unsuitable riser would cause macro porosity or surface sink. When the pouring temperature decreased to a certain value, there was no macro porosity or surface sink. It could provide a potential method to simplify the feeding process and improve the casting quality.

Leidenfrost levitation of a spherical particle above a liquid bath: Evolution of the vapour-film morphology with particle size

We consider a spherical particle levitating above a liquid bath owing to the Leidenfrost effect, where the vapour of either the bath or sphere forms an insulating film whose pressure supports the sphere’s weight. Starting from a reduced formulation based on a lubrication-type approximation, we use matched asymptotics to describe the morphology of the vapour film assuming that the sphere is small relative to the capillary length (small Bond number) and that the densities of the bath and sphere are comparable. We find that this regime is comprised of two formally infinite sequences of distinguished limits which meet at an accumulation point, the limits being defined by the smallness of an intrinsic evaporation number relative to the Bond number. These sequences of limits reveal a surprisingly intricate evolution of the film morphology with increasing sphere size. Initially, the vapour film transitions from a featureless morphology, where the thickness profile is parabolic, to a neck–bubble morphology, which consists of a uniform pressure bubble bounded by a narrow and much thinner annular neck. Gravity effects then become important in the bubble leading to sequential formation of increasingly smaller neck–bubble pairs near the symmetry axis. This process terminates when the pairs closest to the symmetry axis become indistinguishable and merge. Subsequently, the inner section of that merger transitions into a uniform-thickness film that expands radially, gradually squishing increasingly larger neck–bubble pairs into a region of localised oscillations sandwiched between the uniform film and what remains of the bubble whose radial extent is presently comparable to the uniform film; the neck–bubble pairs farther from the axis remain essentially intact. Ultimately, the uniform film gobbles up the largest outermost bubble, whereby the morphology simplifies to a uniform film bounded by localised oscillations. Overall, the asymptotic analysis describes the continuous evolution of the vapour film from a neck–bubble morphology typical of a Leidenfrost drop levitating above a flat solid substrate to a uniform-film morphology which resembles that in the case of a large liquid drop levitating above a liquid bath.

On-machine measurement and temperature compensation method of NURBS surface interpolation for semicircular narrow neck thickness based on ultra-precision machine tool

Abstract Flexible joint is a typical low-rigidity micro part, which has four narrow neck structures evenly distributed around its central axis. In the ultra-precision machining process, It is crucial to control the dimensional accuracy of the narrow necks to improve stiffness consistency. However, the limited space of the neck structures and the high accuracy requirements bring extremely difficulties to the measuring process. In this paper, a novel on-machine measurement method for the semicircular narrow necks was presented and a measuring device was developed based on the combination of high linearity incremental measurement method and on-machine measurement technology. Moreover, the uncertainty of measurement error was analyzed in detail. In view of the measurement error caused by temperature drift, a compensation method based on non-uniform rational B-spline (NURBS) surface interpolation was used to enhance the measurement accuracy. The experimental results showed that the measurement accuracy enhanced over 30% after compensation, which met the measuring requirement of flexible joint.

Does hip structural analysis confer additional benefit to routine BMD assessment in postmenopausal women with hip fracture? A study from a tertiary center in southern India.

There is limited information with regard to comprehensive bone health in Indian postmenopausal women with neck of femur fracture. We studied the bone mineral density (BMD), trabecular bone score (TBS), proximal hip geometry, and bone mineral biochemistry in postmenopausal women with and without femoral neck fractures. This was a cross-sectional study conducted at a tertiary care center in South India. BMD, TBS, and hip structural analysis (HSA) were assessed using a dual-energy X-ray absorptiometry (DXA) scanner. Bone mineral biochemical profiles were also studied. A total of 90 postmenopausal women with acute femoral neck fracture with mean (SD) age of 63.2 (6.1) years and 90 age-matched controls were included. The prevalence of osteoporosis was higher among cases as compared to controls (83.3% vs 47.8%; P < 0.001). Degraded bone microarchitecture (TBS value < 1.200) was more frequent among women with hip fracture as compared to controls (46.7% vs 31.1%; P = 0.032). Cross-sectional moment of inertia (CSMI) was significantly lower at the narrow neck (NN) and inter-trochanteric (IT) region in cases (P < 0.05) and buckling ratio (BR) was significantly higher at all three sites in postmenopausal women with femoral neck fracture as compared controls. Multivariate logistic regression analysis showed that femoral neck osteoporosis, low CSMI at NN and high BR at NN and femoral shaft emerged as factors significantly associated with femoral neck fractures. This study highlights that impaired parameters of proximal hip geometry and a low trabecular bone score may be significantly associated with femoral neck fractures in postmenopausal women.