Half Centimeter Research Articles

Belly up or belly down: Effect of body position on snout vent length and total length measurements in American crocodiles (Crocodylus acutus)

Abstract The interpretation of morphometric data is relevant to understanding biological phenomena. Currently, little is known about the effect of body position on morphometric measurements in crocodylians as well as the extent to which these data are interchangeable. We investigated the effect of body position on snout-vent-length (SVL) and total-length (TL) measured ventrally (belly up) and dorsally (belly down) on 725 Crocodylus acutus (mean TL ventral and dorsal 68.49 cm and 69.82 cm, range = 33.1-185.4 cm and 33.8-185.4 cm) across South Florida, United States. We found evidence that body posture significantly influences SVL and TL measurements. However, regardless of body position, the variation found in SVL was less than 1 mm, and for TL was on average only 3 mm. We concluded that even though there is a difference when measuring American crocodiles belly up and belly down, there is a minimal effect on the outcome (less than half centimeter), which falls within the normal measurement instrument error (i.e., measurement tape) even more so under field conditions. If researchers concur that this is an acceptable error, then SVL and TL measurements taken belly up or belly down can be used interchangeably.

Reproductive aspects of freshwater unionid mussel sperm: Seasonal dynamics, male-to male variability, and cell quantification

Freshwater unionid mussel diversity is decreasing because of species extirpation or extinction. While little can be done to recover lost species, there is an opportunity to develop techniques to save other species. This can be facilitated through gene banking and assisted reproduction. Unfortunately, limited information is available on mussel reproduction, especially relating to sperm quality. Objectives, therefore, were to quantify seasonal changes in sperm concentration and morphology for two unionid mussels, Ligumia subrostrata and Lampsilisstraminea, measure intraspecific heterogeneity for sperm morphometry, and develop an efficient method to quantify sperm concentration using a microspectrophotometer. There were no differences in sperm concentration when cells were extracted from the center or at a half centimeter on either side of the visceral mass, during the spawning season. There was a seasonal change in sperm concentration, such that concentration for L. subrostrata ranged from 1.1 × 109 to 19.60 × 109 cells/mL with there being the largest counts between 26 September to 7 November. L. straminea sperm concentration was greatest (20.0 × 109 cells/mL) on 13 September and subsequently decreased. Sperm were uniflagellated and SEM results for L. subrostrata and L. straminea showed mean head length and width (mid-spawning) were 3.38 ± 0.04 μm and 1.61 ± 0.01 μm and 3.37 ± 0.04 μm and 1.61 ± 0.01 μm, respectively. There were close (R2 ≥ 0.85) quadratic associations between hemocytometer counts and absorbance (300, 600, 700 nm). These results provide baseline information to further investigate sperm quality, fertilizing capacity, and cryopreservation for freshwater mussels.

Experimental study to estimate the discharge coefficient over inclined side spillway

Abstract: Weir is usually used in different hydraulic purposes, mainly for head discharge-water relationship in channels. In this research, the flow has been carried out over the side of spillway using three cases of crest inclination by means of increasing one side of the weir a half centimeter each time with constant crest length equal to 15 cm. This means that the angle θ equals to (1.91˚, 3.82˚ and 5.71˚) respectively towards of the flow and is opposite to the flow with decreasing a half centimeter. Also in case of the breadth is horizontal (θ=0), seven cases have been tested. It is known that the greater amount of discharge occurs when the breadth is horizontal (θ=0). In case of the inclination of the weir is inclined opposite to the flow direction, the discharge is greater than that of which the weir inclined towards the flow direction for all cases of inclination. The greater discharge was obtained when decreasing the angle, which is opposite to the flow direction. The amount of discharge over the side of weir decreases by increasing the angle of the slope opposite to the direction of the flow and become more decreasing in case the inclination of side weir towards the flow. In case of increasing the angle of inclination in flow direction, the amount of discharge over side weir will be decreased. The effect of Froude number has also studied with the discharge coefficient and found that, they are proportionally related to each other. Also the water surface profile along the side spillway weir is studied and taken under consideration theoretically and experimentally in this research.

Anatomic and Patient Risk Factors for Postoperative Periprosthetic Hip Fractures: A Case-Control Study

BackgroundPeriprosthetic fracture remains a major source of reoperation following total hip arthroplasty (THA). Within 90 days of surgery, fractures may occur spontaneously or with minor injury and are therefore more likely related to patient factors including anatomic variation. MethodsFrom 2008 to 2018, 16,254 primary THAs were performed at our institution; of those, 48 were revised for periprosthetic fracture within 90 days of surgery. A control group of 193 patients undergoing THA for hip osteoarthritis (OA) was randomly selected from the source population. We excluded patients with genetic bone disease and THA performed for hip fracture. We used logistic regression to analyze associations between patient factors (demographics, anatomical factors, comorbidities, surgical technique, and implants) and odds of 90-day periprosthetic fracture. ResultsIncreased age was significantly associated with fracture (P = .002), as was female gender (P = .046). After adjusting for age and gender, absence of contralateral OA was associated with increased odds of fracture relative to patients with contralateral OA (odds ratio [OR] 3.85, 95% confidence interval [CI] 1.60-9.29), as was having a contralateral THA in place (OR 3.70, 95% CI 1.59-8.60). The neck-shaft angle, femoral offset, and the Dorr classification were not associated with increased odds of fracture. Additionally, the distance from the tip of the trochanter to the top of the femoral head was associated with increased odds of fracture per half centimeter (OR 1.48, 95% CI 1.14-1.93). ConclusionRisk of early postoperative periprosthetic fracture following THA is increased with age, female gender, and increasing distance from the greater trochanter to the top of the femoral head; and decreased in the setting of contralateral hip OA. The trochanter-head distance correlation with periprosthetic hip fracture indicates that the preoperative anatomy may influence PPF, particularly regarding how that anatomy is reconstructed.

Unusual case of a fatal upper esophageal trauma caused by a toothpick

The authors report the case of the unexpected death of a fifty-year-old female found by her partner in the bathroom floor. External examination revealed some contusions dispersed by different corporal areas and an unusually placed green discoloration of the anterior cervical region. After neck dissection and opening the esophagus, a three and a half centimeter wooden toothpick fragment was found at the upper region, covered by a purulent substance associated with puncture wounds. Histopathological and microbiological studies revealed “acute bilateral cervical cellulitis” and Klebsiella Oxytoca, respectively. Further investigation revealed that during the five days prior to her death, the victim was observed twice in an emergency department with complains of throat discomfort after eating some bread with salami. X-Ray and a laryngoscopy were performed but did not reveal any significant findings. Due to the victim's medical history, she was evaluated by a psychiatrist that dismissed a non-somatic setting due to the type of complains and the elevation of blood inflammatory parameters. Rinopharyngitis was then assumed as the most likely diagnosis and was treated accordingly. The victim died the following day. This case reports an unusual fatal traumatic lesion to the upper esophagus that is a very important remainder, particularly for clinical practitioners, to maintain a high degree of suspicion, avoid diagnostic biases such as those related to psychiatric disorders and meticulously evaluate patients in order to deliver the most evidence-based diagnosis possible. To the best of the authors' knowledge there are no other cases described in the literature of a death caused by esophageal toothpick lesion.

Improved Anatomical Specificity of Non-invasive Neuro-stimulation by High Frequency (5 MHz) Ultrasound.

Low frequency ultrasound (<1 MHz) has been demonstrated to be a promising approach for non-invasive neuro-stimulation. However, the focal width is limited to be half centimeter scale. Minimizing the stimulation region with higher frequency ultrasound will provide a great opportunity to expand its application. This study first time examines the feasibility of using high frequency (5 MHz) ultrasound to achieve neuro-stimulation in brain, and verifies the anatomical specificity of neuro-stimulation in vivo. 1 MHz and 5 MHz ultrasound stimulation were evaluated in the same group of mice. Electromyography (EMG) collected from tail muscles together with the motion response videos were analyzed for evaluating the stimulation effects. Our results indicate that 5 MHz ultrasound can successfully achieve neuro-stimulation. The equivalent diameter (ED) of the stimulation region with 5 MHz ultrasound (0.29 ± 0.08 mm) is significantly smaller than that with 1 MHz (0.83 ± 0.11 mm). The response latency of 5 MHz ultrasound (45 ± 31 ms) is also shorter than that of 1 MHz ultrasound (208 ± 111 ms). Consequently, high frequency (5 MHz) ultrasound can successfully activate the brain circuits in mice. It provides a smaller stimulation region, which offers improved anatomical specificity for neuro-stimulation in a non-invasive manner.

SU‐E‐T‐193: Commissioning of An IntraOp Mobetron

Purpose:This study will describe the commissioning process of an Intra‐Op Mobetron following the guidance of TG72 and includes a detailed method for measuring gap factors.Methods:Beam data was collected for 6, 9, and 12MeV electrons on the Mobetron using a PTW water tank and a Markus chamber. Commissioning data was collected for 3 sets of cones (0°, 15°, and 30° with respect to the water surface) that ranged in size from 3cm to 10cm diameter in half centimeter increments. Profiles were collected at six depths for all integer cones. PDI's were taken for all cones in a path perpendicular to the water surface and then converted to dose using MEPHYSTO's internal algorithm. The depth of maximum dose was determined from the PDD's and used for measurement of output factors. Output factors were normalized to the 10cm flat cone. Gap factors were measured for all flat cones by raising the cone away from the water surface in defined gaps. These gap factors were measured at dmax for gaps of 1cm to 5cm in 1cm increments Gap factors and effective SSD values were calculated.Results:Output factors measured for all cones were within 3% of the representative beam data for flat cones. There is no published data on beveled cones, but the angled cone output factors agreed with the flat cones within 5%. Gap factors follow a linear pattern with the output decreasing 3–7% per centimeter gap depending on the size of the cone and energy. Effective SSD values calculated and fit a 3rd order polynomial curve with R2&gt;0.98 for all energies.Conclusion:Commissioning of an Intra‐Op Mobetron was completed with general agreement to published data. New data was published for beveled cones and a method for determining gap factors was established.

The Association Between Abdominal Sagittal Diameter And Cardio-metabolic Risk In Obese Women Undergoing Weight Loss

Visceral adiposity has been reported to be related to an increased prevalence of the metabolic syndrome. Sagittal diameter may be a low-cost, safe method to assess central adiposity that may be related to metabolic disregulation. PURPOSE: To explore relationships between abdominal sagittal diameter and serum lipids that are known to be associated with cardio-metabolic risk. METHODS: 117 overweight and obese women took part in a 16 week behavioral weight loss intervention with a strong emphasis on increasing physical activity. Weight, sagittal diameter, and serum lipids were assessed at baseline and at week-16. Sagittal diameter was measured while participants were in the supine position, measured as the distance between the umbilicus and the small of the back. Measurements were taken to the nearest half centimeter using an aluminum sliding broad blade anthropometer. RESULTS: At baseline, participants averaged 45.7±9 yrs, 78.4±9 kg and BMI was 29.9±3 kg/m2. Weight was reduced significantly (p<.001) to 71.3±9 kg at week-16. Sagittal diameter averaged 23.3±2.5 cm at baseline and reduced significantly (p<.01) to 20.9±2.5 cm at week-16. At baseline, sagittal diameter was significantly (all p's <.01) related to triglycerides (.27), high-density lipoproteins (HDL) cholesterol (-.30), free-fatty acids (.27), and systolic blood pressure (.25). Changes in sagittal diameter over 16 weeks were also significantly (p<.01) associated with changes in low-density lipoproteins (LDL) cholesterol (.22) and free-fatty acids (.16). An ANCOVA was used to compare variables of interest adjusting for body weight whereby patients were collapsed into thirds of sagittal diameter. Patients with the lowest sagittal diameter had more favorable (p<.05) systolic blood pressure, triglycerides, HDL cholesterol, cholesterol:HDL ratio, fasting glucose, and fasting insulin than those in the highest group. CONCLUSIONS: Sagittal diameter may offer health care professionals a quick, safe, and low-cost method to estimate central adiposity, which has been shown to be linked to the metabolic syndrome.

The Effect of Breed, Age and Fasting Status on Macro-nutrient Composition of Meat from Goat Breeds of North-Western Nigeria

Carcasses of 32 male goats matching Conformation Score 3 of the Australian standard for live goat evaluation, were randomly assigned to a 2x2x2 factorial experiment involving two breeds (Sahel, Sokoto Red), two ages (young, mature) and two fasting states (fasted, non-fasted) with four replicates. one and a half centimeter thick samples of the Longissimus dorsi muscle cut between the 12th and 13th ribs of the right halves of the carcasses were analyzed according to AOAC (1990) and found to contain an average of 75.59, 19.19, 3.67 and 1.55% moisture, protein, fat and total ash, respectively. None of the nutrients was affected significantly (P>0.05) by breed, age and fasting status (P>0.05). This may imply that the three factors need not feature as major considerations in the choice of goat meat for nutritional advantage in the study area.

The establishment of chronic rejection model of rat's aortic transplantation

Objective To establish an aortic transplantation model in the rat. Methods A thoracic aorta to abdominal aorta interposition transplant model in the rat was established. The male Lewis rats were used as donors and the female Brown Norway(BN) rats were used as recipients.Intercepted the thoracic aorta of lewis rats about one and a half centimeter. Transplanted it on the abdominal aorta of BN rats. The activity and weight change of BN rats were observed everyday until 1 week after transplantation. Then observed these index one time a week. The transplanted aortas were harvested at 8 weeks after transplantation. The intimal thickening were observed by pathological. The expression of CD3,CD68 and α-actin on transplanted aorta were observed by immunohistochemistry. Resuts All operations were finished within 2 hours. No recipients died during operation. All recipients could survival more than 8 weeks. The symptoms of bowing back, hair shedding and weight loss was appeared after transplantation. The weight of the rats were upturn at 4 or 5 days after transplantation. About 1 week after transplantation, all situations of the rats were recovery to the lever before transplantation. 8 weeks after transplantation the intimal thickening of the transplanted aortas were observed obviously by pathological. And the expressions of CD3, CD68 and α-actin on aortic allograft were observed. Conclusion The intimal thickening and the expressions of CD3, CD68 and α-actin on aortic allograft were typical expressions of chronic rejection. So this aortic transplantation model is feasible and reliable for studying chronic rejection. Key words: Aorta; Vessel transplantation; Allograft rejection; Animal model

SU-FF-T-398: The Implications of Monitor Unit and SSD Rounding Errors On Delivered Dose

Purpose: To investigate the individual and overall contributions of Monitor Unit and SSD rounding errors on delivered dose for different treatment regions. Method and Materials: Treatment planning computers are configured to calculate treatment monitor units (MUs) to at least one decimal place, but because the ion chambers in many linear accelerators can not measure radiation to this accuracy, treatment plan MUs are often rounded off to the nearest whole number. Further more, treatment planning systems can calculate radiation source-skin distances (SSDs) to millimeter accuracy, while the optical distance indicators (ODIs) on linear accelerators generally require rounding to the nearest half centimeter. Acceptable treatment plans were generated to obtain MUs and SSDs to at least one decimal places. Treatment MUs and SSDs from these plans were then rounded and put back into the plans to obtain the real world deliverable plans. The isodose distributions and Dose-Volume Histograms (DVHs) for individual and total contributions of these two rounding errors were then compared and analyzed for different treatment regions. Results: Our results show distortions of isodose distributions and Dose-Volume Histograms (DVH) as a result of the compounded rounding errors in MU calculations and ODI SSD readings. In particular, we found that normal tissue dose constraints, which appeared to be satisfied in the original computer plan, could be exceeded by up to 6% when rounding errors were taken into account, particularly in sites with relatively short radiation effective path-lengths, like the head and neck. The effects of MU rounding error appear to be greater than those ODI SSD rounding error and less significant for sites with long radiation effective path lengths such as lung tumors. Conclusions: This work indicates the potential overdose or underdose as a result of MU and SSD rounding errors.

Lithological variation with depth and decoupling of maturity parameters in Apollo 16 regolith core 68001/2

Using ferromagnetic resonance (FMR) and instrumental neutron activation analysis (INAA), we have determined the maturity (surface exposure) parameter I s FeO and concentrations of twenty-five chemical elements on samples taken every half centimeter down the 61-cm length of the 68001/2 regolith core (double drive tube) collected at station 8 on the Apollo 16 mission to the Moon. Contrary to premission expectations, no ejecta or other influence from South Ray crater is evident in the core, although a small inflection in the I s FeO profile at 3 cm depth may be related the South Ray crater impact. Regolith maturity generally decreases with depth, as in several previously studied cores. We recognize five compositionally distinct units in the core, which we designate A through E, although all are similar in composition to each other and to other soils from the Cayley plains at the Apollo 16 site. Unit A (0–33 cm) is mature to submature throughout ( I s FeO : 34–89 units) and is indistinguishable in composition from surface soils collected at station 8. Unit B (33–37 cm) is enriched slightly in a component of anorthositic norite composition. Unit D (42–53 cm) is compositionally equivalent to 80 wt% Unit-A soil plus 20 wt% Apollo-16-type dimict breccia consisting of subequal parts anorthosite and impact-melt breccia. Compared to Unit A, Unit E (53–61 cm) contains a small proportion (up to 4%) of some component compositionally similar to Apollo 14 sample 14321. Unit C (37–42 cm) is unusual. For lithophile and siderophile elements, it is similar to Units A and D. However, I s FeO is low throughout the unit (<30 units) and in a bluish-gray zone at 41 cm depth I s FeO drops to 1.6 units, the lowest value that we have observed in several hundred Apollo 16 soil samples. Samples from the bluishgray zone also have low Zn concentrations, <10 μg/g, compared to 20–30 μg/g for the rest of the core. Although both values are consistent with fragmented rock material that has received virtually no surface exposure, the abundance of agglutinates in the bluish-gray soil of Unit C is moderately high, typical of a submature soil that would ordinarily have I s FeO ≈ 30 . We believe that the anomalously low values of I s FeO and Zn concentration result because the soil was heated to ∼800–1000 °C, probably during an impact. This temperature range is sufficient to volatize the surface-correlated Zn and agglomerate the nanophase metal giving rise to the FMR signal but is not great enough to sinter the soil. Alternatively, the unusual soil interval may represent a disaggregated or incipient regolith breccia, although there is no significant difference in the texture or clast-matrix relationships between Unit C and adjacent units.

The cleavage plane in semi-closed endarterectomy of the superficial femoral artery: A histologic study

Purpose: The purpose of this study was to determine the cleavage plane in semiclosed endarterectomy of the superficial femoral artery, a histologic study of endarterectomy cores of 10 consecutive patients was performed. Superficial femoral artery occlusive disease consisted of multiple stenoses in one and an occlusion in the other cases.Methods: Microscopic paraffin cross-sections were made every half centimeter of the endarterectomy core. The sections were stained with hematoxylin-eosin and with elastica van Gieson. Microscopic studies were conducted of a total of 484 sections. Intima, internal elastic membrane, media, external elastic membrane, and adventitia were identified, if present.Results: When the procedure of separating the diseased intima from the remainder of the arterial wall was commenced, the cleavage plane was located between the internal elastic membrane and the media in most cases. In two cases the cleavage plane was located inside the intima, and in one case parts of the media were removed as well. During passage of the ring stripper through the artery, the location of the cleavage plane changes and extends into the media. In one patient a residual stenosis was located in the segment of the core in which only the intima and internal elastic membrane were removed. In two patients the endarterectomy core contained parts of the external plastic membrane as well. During passage of the ring stripper through the artery, the location of the cleavage plane changes. In some segments the media is left intact, whereas in other segments the media is partially or totally removed. The reason for the variability of the cleavage plane rests in the nature of the pathologic behavior of the atheroma. The tissue necrosis that is part of the atheromatous complex frequently dips beyond the internal elastic membrane into the media and even into the external elastic membrane and adventitia.Conclusions: The question remains as to whether the location of the cleavage plane has an influence on the long-term results of endarterectomy. Long-term follow-up studies are required to supply us with the answer.

Spatial distribution of dinoflagellate resting cysts in Recent sediments of Kiel Bight, Germany (Baltic Sea)

Abstract The occurrence and distribution of dinoflagellate resting cysts in Recent sediments was investigated at 9 locations in Kiel Bight, Baltic Sea. The assemblage comprised 25 known cyst species and 4 unknown cyst types and is characterized by the dominance of Protoperidinium cf. divergens with a maximal abundance of 1695 living cysts/cm3 in the upper half centimeter. Cysts of the potentially toxic dinoflagellates of the Alexandrium excavatum/tamarense group and A. minutum were scarce. Micro-reticulate resting cysts of the toxic, unarmoured Gymnodinium catenatum, whose motile cell has not been recorded in Northern European waters, are reported for the first time from Recent sediments of the Baltic Sea. In the top 2-cm of sediment up to 1200 living dinoflagellate cysts/cm3 were found and the following trends were noted: Cysts were primarily associated with sediments dominated by mud, sandy stations exhibited the lowest cyst abundance. Highest cyst concentrations were found at the deepest stations and t...

The Meiobenthos Along a Mediterranean Deep‐Sea Transect off Calvi (Corsica) and in an Adjacent Canyon

Abstract. Meiobenthos densities (excluding hard‐shcllcd foraminifcrans) were compared along a Mediterranean deep‐sea transect off Calvi (Corsica) and in an adjacent canyon. Chloroplastic Pigment Equivalent values (CPE) provided an estimate of the amount of primary production reaching the bottom.The stations along the transect were characterized by a low CPE content of the sediment, decreasing with increasing station depth. CPE values in the canyon were much higher, which probably resulted from import of material from the adjacent bay of Calvi. Similarly, meiobenthos densities along the transect were much lower than at comparable depths along the canyon.Meiobenthos density was significantly and positively correlated with CPE values.Nematodes were the most abundant taxon at all stations, followed by copepods + nauplii and the soft‐shelled foraminiferans. The meiobenthos was most abundant in the upper half centimeter. Nematode and foraminiferan densities tended to decline less rapidly with increasing depth into the sediment. Specimens belonging to the recently described phylum Loricifera, larvae of the parasitic crustacean class Tantulocarida, and fragments of an infaunal Xenophyophoria (large protozoans) are reported for the first time from the Mediterranean.

Concentration Profiles of Platelet‐Sized Latex Beads for Conditions Relevant to Hollow‐Fiber Hemodialyzers

A freeze-capture method was used to obtain the concentration profiles of platelet-sized latex beads (2.5 microns diameter) in saline-based red cell suspensions flowing through tubes with inner diameters of 135 and 200 microns. Without red cells the concentration profile exhibited a slight deficit near the wall. For hematocrits from 15 through 52%, the concentration profile exhibited a near-wall excess of beads, from two to eight times the central concentration. Near-wall excesses were small or nonexistent in the first half centimeter of the tube. For hematocrits of 15 and 30%, the profile and near-wall excess were equal at stations 2 cm or more from the entrance. These results suggest that there is a flow-driven mechanism that moves platelet-sized beads toward, but not to, the wall.

Balloon embolectomy catheters in small arteries: A technique to prevent excessive shear forces

Balloon embolectomy catheters were studied in canine common carotid arteries (2 to 3 mm) in vitro to evaluate a technique of preventing excessive shear forces and to examine the effect of blood within the lumen. Each balloon was studied at 25, 75, 125, or 150 mm Hg lateral wall pressure. Shear forces were recorded in 16 vessels when the balloons were distended before catheter withdrawal, and these data were compared with forces recorded when the balloons were distended during catheter withdrawal. Results showed that distention of the balloon during withdrawal reduced shear forces 43.8% to 55.8% (p < 0.05). In other experiments shear forces were recorded when the lumen was lubricated with heparinized saline solution, and these were compared with forces recorded when the lumen was lubricated with heparinized whole blood. The presence of blood in the lumen reduced shear forces 23.4% to 52.9% (p < 0.05). From these studies it is recommended that during embolectomy in patients (1) the balloons be distended during the first half centimeter or centimeter of catheter withdrawal to prevent excessive shear forces and (2) that residual blood in the vessel lumen proximal to the point of embolic obstruction be accepted without concern, provided adequate heparinization has been achieved.

The effects of electric current on fracture healing clinical observation

The electrical current has been applied for fracture healing. Bared tip, one and half centimeter in length of a multistrand stainless-steel wire insulated with Teflon was inserted into the bone marrow as a cathode and the anode was fixed on the skin. The power pack with 9 volt battery modified to discharge a constant current of 10 microamperes inspite of variable resistence was connected in between both poles. All the patients were sustained either of the fracture of the femur or the tibia.Five patients with non-union, five with delayed union and four with fresh fracture were included in this series. Complete healing of fracture was obtained in thirteen out of fourteen cases. Electrical current thus applied might be said to enhance bone formation and is promising for the treatment of fractures, especially for non-union or delayed union.