Journal articles on the topic 'Head size ratio'
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Taura, Tomoyuki, Masao Noguchi, Seiji Tsuji, Hirofumi Dokawa, Ai Mori, and Narihiro Okazaki. "Review of Enlargement Ratio of the Femoral Head: Using a Ring to Decide Femoral Head Size." Orthopedics & Traumatology 57, no. 4 (2008): 548–52. http://dx.doi.org/10.5035/nishiseisai.57.548.
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Baker, Robert L., and Blair W. Feltmate. "Development of Ischnura verticalis (Coenagrionidae: Odonata): Effects of Temperature and Prey Abundance." Canadian Journal of Fisheries and Aquatic Sciences 44, no. 9 (September 1, 1987): 1658–61. http://dx.doi.org/10.1139/f87-202.
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Increased food availability increased rate of development within an instar, head width ratio (ratio of headwidth of later instar over head width in previous instar), and weight per unit head width of newly molted larval Ischnura verticalis (Say) (Coenagrionidae: Odonata) reared in the laboratory. Temperature affected rate of development but not weight per unit head width or head width ratio. Mortality was not affected by any treatment. Rate of development was negatively correlated with both weight per unit head width and head width ratio. Results suggest that the developmental process has evolved to reduce risks associated with small size at the expense of a more rapid development.
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Waddell, Bradford S., Chelsea Koch, Myra Trivellas, Jayme C. Burket, Timothy Wright, and Douglas Padgett. "Have large femoral heads reduced prosthetic impingement in total hip arthroplasty?" HIP International 29, no. 1 (May 7, 2018): 83–88. http://dx.doi.org/10.1177/1120700018761153.
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Background: Prosthetic impingement is implicated in dislocation after total hip arthroplasty (THA). While use of larger diameter femoral heads reduces the incidence of dislocation, the effect of larger heads upon impingement rate is unknown. We assessed retrieved THA components for evidence of impingement to determine if large femoral heads reduced the rate of impingement in primary THA and what factors might influence impingement. Methods: Liners from 97 primary THAs retrieved at revision arthroplasty were scored for evidence of impingement, defined as wear or deformation on the rim of the component. Component inclination and version were measured from anteroposterior and cross-table lateral radiographs. Results: Independent of revision diagnosis, 77% of liners demonstrated evidence of impingement. Impingement was less prevalent and less severe as head size increased. Severe impingement was observed in 50% of the liners with 28-mm heads, 15% of liners with 32-mm heads, and 21% of liners with 36-mm heads. Regardless of head size, 76% of liners revised for instability demonstrated impingement. Decreased head-neck ratio, use of an elevated liner, increased length of implantation, and increased version were associated with increased severity of impingement. Discussion: We showed that larger head sizes are associated with decreased incidence of impingement on retrieved acetabular liners when compared to smaller head sizes. Larger heads have reduced but not eliminated impingement, which remains a potential source of instability.
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Jia, Xiang, Jian Sheng Liu, Hong Ping An, and Min Qin. "Forming Technology and Simulation of Large Head Forgings." Key Engineering Materials 831 (February 2020): 64–70. http://dx.doi.org/10.4028/www.scientific.net/kem.831.64.
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Head forging is an indispensable part of major technical equipment, which is required to produce high quality products because of its large volume and complex structure and long service under high temperature and high pressure. By means of DEFORM-3D numerical simulation and scaling experiment, the dynamic recrystallization dynamics model of SA508-3CL steel is established. Meanwhile, the head forming scheme is designed. The effects of different blank height-diameter ratio size, punch shape size and upper and lower die matching relationship on forging forming are emphatically analyzed. Finally, the reasonable head forming scheme is determined, and the 1:8 head forming scale test is carried out. The results show that the size of the head forging basically coincides with the design size and meets the load of the hydraulic press, which proves the rationality of the forming process of the head. The study provides a theoretical basis for the manufacture of the same type of large variable wall thickness head forgings.
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Suzuki, Hidenori, Shintaro Beppu, Daisuke Nishikawa, Hoshino Terada, Michi Sawabe, and Nobuhiro Hanai. "Lymph Node Ratio in Head and Neck Cancer with Submental Flap Reconstruction." Biomedicines 10, no. 11 (November 14, 2022): 2923. http://dx.doi.org/10.3390/biomedicines10112923.
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This study aimed to investigate the relationship between the lymph node ratio (LNR) and survival results of patients with head and neck squamous cell carcinoma (HNSCC) reconstructed by a submental artery flap (SMAF) to limit tumor size. This study retrospectively recruited 49 patients with HNSCC who underwent both primary resection and neck dissection with SMAF reconstruction. The LNR was the ratio of the number of metastatic lymph nodes to the sum number of examined lymph nodes. A LNR of 0.04 was the best cut-off value for HNSCC-specific death on receiver operating curve analysis. Patients with LNRs > 0.04 were univariately related to cancer-specific, disease-free, distant metastasis-free, and locoregional recurrence-free survival than those with LNRs ≤ 0.04 by log-rank test. In a Cox’s proportional hazards model with hazard ratio (HR) and 95% confidence interval (CI) adjusting for pathological stage, extranodal extension and or surgical margins, the LNR (>0.04/≤0.04) predicted multivariate shorter cancer-specific (HR = 9.24, 95% CI = 1.49–176), disease-free (HR = 3.44, 95% CI = 1.23–10.3), and distant metastasis-free (HR = 9.76, 95% CI = 1.57–187) survival. In conclusion, LNR for patients of HNSCC with SMAF reconstruction for limited tumor size was a prognostic factor for survival outcomes.
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Ai, Heng Yu, Ming Ming Wang, Lu Han, Burigude, Bo Wei, and Yan Qiu Jia. "Features on Head Loss of Flocculation Tank Installed with Small Mesh Grid." Advanced Materials Research 777 (September 2013): 424–29. http://dx.doi.org/10.4028/www.scientific.net/amr.777.424.
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Small mesh grid is mostly used as flocculation equipment in present water plant, and its head loss is closely related to flocculation effect. Flocculation tank installed with several grid groups in different mesh sizes were tested with a view to evaluating its head loss characteristics, including the frictional and local head losses. The tests were carried out at pilot scale, using a steel tank as flocculation basin. The grids are made of plastic material and the cross section size of the grid trips is 7 mm in width and 2 mm in height. The results indicate that relative roughness is most associated with frictional resistance coefficient (FRC), whereas Reynolds number was unrelated to that. The ratio of frictional head loss to total head loss of the basin does not vary with the variation of channel velocity, and the ratio is always less than 6% in this case. Local resistance coefficient (LRC) decreases with the increase of mesh size. In order to improve the utilization rate of head loss, the preferred mesh size of the grid should be 30-40 mm. The optimal space between the neighboring grid layers can maximize the utilization of turbulent kinetic energy loss generated by grids.
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VERDADE, L. M. "Regression equations between body and head measurements in the broad-snouted caiman (Caiman latirostris)." Revista Brasileira de Biologia 60, no. 3 (August 2000): 469–82. http://dx.doi.org/10.1590/s0034-71082000000300012.
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In the present study, regression equations between body and head length measurements for the broad-snouted caiman (Caiman latirostris) are presented. Age and sex are discussed as sources of variation for allometric models. Four body-length, fourteen head-length, and ten ratio variables were taken from wild and captive animals. With the exception of body mass, log-transformation did not improve the regression equations. Besides helping to estimate body-size from head dimensions, the regression equations stressed skull shape changes during the ontogenetic process. All age-dependent variables are also size-dependent (and consequently dependent on growth rate), which is possibly related to the difficulty in predicting age of crocodilians based on single variable growth curves. Sexual dimorphism was detected in the allometric growth of cranium but not in the mandible, which may be evolutionarily related to the visual recognition of gender when individuals exhibit only the top of their heads above the surface of the water, a usual crocodilian behavior.
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Rumrich, Isabell Katharina, Otto Hänninen, Matti Viluksela, and Kirsi Vähäkangas. "Effect of Grandmaternal Smoking on Body Size and Proportions at Birth." International Journal of Environmental Research and Public Health 18, no. 9 (May 7, 2021): 4985. http://dx.doi.org/10.3390/ijerph18094985.
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Many long-term adverse effects of smoking during pregnancy are known. Increasingly, adverse effects in the grandchild after grandmaternal smoking during pregnancy are reported. We explored this in a birth cohort of 24,000 grandmother–mother–child triads identified from the Finnish Medical Birth Register in 1991–2016. Multiple logistic regression was used to analyze the association between any smoking during pregnancy by both grandmother and mother, or only grandmother or mother on adverse birth outcomes. No smoking by neither grandmother nor mother was used as the reference. As endpoints, preterm birth, low birth weight, small for gestational age (birth weight, birth length, head circumference), and body proportionality (low ponderal index, high brain-to-body ratio, high head-to-length ratio) were included. Smoking by both grandmother and mother was consistently associated with higher risks than smoking only by the mother. Birth length and weight were especially sensitive to (grand)maternal smoking. In conclusion, the combined effect of grandmaternal and maternal smoking is associated with higher risks than only maternal smoking.
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Willigenburg, NW, RA Bouma, VAB Scholtes, VPM van der Hulst, DFP van Deurzen, and MPJ van den Bekerom. "Does the innate relative size of the humeral head and glenoid affect the risk of anterior shoulder instability?" Shoulder & Elbow 11, no. 6 (October 23, 2018): 424–29. http://dx.doi.org/10.1177/1758573218805099.
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Background Bony lesions after shoulder dislocation reduce the joint contact area and increase the risk of recurrent instability. It is unknown whether the innate relative sizes of the humeral head and glenoid may predispose patients to shoulder instability. This study evaluated whether anterior shoulder instability is associated with a larger innate humeral head/glenoid ratio (IHGR). Methods We evaluated CT scans of 40 shoulders with anterior shoulder instability and 48 controls. We measured axial humeral head diameter and glenoid diameter following native contours, discarding any bony lesions, and calculated IHGR by dividing both diameters. Multivariate logistic regression determined whether the IHGR, corrected for age and gender as potential confounders, was associated with anterior shoulder instability. Results Mean IHGR was 1.48 ± 0.23 in the group with anterior shoulder instability and 1.42 ± 0.20 in the group without anterior shoulder instability. Measurements for axial humeral head and axial glenoid diameters demonstrated excellent intra-rater reliability (ICC range: 0.94–0.95). IHGR was not significantly associated with anterior shoulder instability (OR = 1.105, 95%CI = 0.118–10.339, p = 0.930). Discussion The innate ratio of humeral head and glenoid diameters was not significantly associated with anterior shoulder instability in this retrospective sample of 88 shoulder CT scans.
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Moskalenko, Valentyna A., and Valeriy P. Kolosha. "Some aspects of evaluating the cost efficiency level in dairy farming." Socio-Economic Problems of the Modern Period of Ukraine, no. 6(146) (2020): 114–19. http://dx.doi.org/10.36818/2071-4653-2020-6-18.
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The problems related to the level of economic efficiency of dairy farming depending on the level of production intensity are analyzed. The paper emphasizes that the theory of costs is one of the basic in economics and the object of constant attention of scientists. The objective of the study is to assess the impact of the level of costs per cow on the efficiency of milk production and test the relative cost efficiency ratio on the example of a set of enterprises. The agricultural enterprises of Harkivska oblast selling milk as part of their marketable products are the object of the study. The set of studied enterprises is divided into five groups with a cost level from UAH 30,000 per cow to more than UAH 60,000 per cow. A clear relationship between the level of costs and the size of enterprises is found. The dependence shows that enterprises with higher production intensities have more livestock and agricultural land. In the group with a cost level of up to UAH 30,000 per head, one enterprise has on average 157 heads and 1,805 hectares of agricultural land, in the group with a cost level of more than UAH 60,000/head – 559 heads and 4,266 hectares of agricultural land. The paper also establishes that the level of costs per cow very closely determines the level of its productivity. In the group with a cost level of up to UAH 30,000 per head, the average productivity of animals was 4,257 kg/head, in the group with a cost level of UAH 40,000 to UAH 50,000 per head – 6,787 kg/head, and with a cost level of over UAH 60,000 per head – 10,178 kg/head. Approbation of the proposed relative cost efficiency ratio made it possible to establish that this parameter allows assessing both economic and technological efficiency of milk production. The value of the relative cost efficiency ratio in terms of income was over 1 in 38 enterprises and, accordingly, less than 1 – in 39 enterprises. The value of the relative cost efficiency ratio in terms of productivity was over 1 in 23 enterprises and lower in 54 enterprises.
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Rumrich, Isabell, Kirsi Vähäkangas, Matti Viluksela, Mika Gissler, Hanna de Ruyter, and Otto Hänninen. "Effects of maternal smoking on body size and proportions at birth: a register-based cohort study of 1.4 million births." BMJ Open 10, no. 2 (February 2020): e033465. http://dx.doi.org/10.1136/bmjopen-2019-033465.
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ObjectivesThe aim of our work was to analyse the effect of maternal smoking on body size and body proportions of newborns when the mother had smoked only during the first trimester, in comparison with continued smoking after the first trimester. Furthermore, we have evaluated how growth restriction associated with maternal smoking contributes to changes in body proportions.DesignRegister-based cohort studySettingMaternal Exposure (MATEX) cohort identified from the Finnish Medical Birth Register.ParticipantsSingleton births without congenital anomalies and missing data (1.38 million) from 1 January 1991 to 31 December 2016.MethodsLogistic regression was used to quantify the effect of maternal smoking, stratified by the maternal smoking status.Outcome measuresBody proportions indicated by low brain-to-body ratio (defined as <10th percentile); high ponderal index and high head-to-length ratio (defined as >90th percentile); small body size for gestational age at birth (defined as weight, length or head circumference <10th percentile) and preterm birth (<37 weeks) and low birth weight (2500 g).ResultsContinued smoking after the first trimester was associated with high ponderal index (OR 1.26, 95% CI 1.23 to 1.28), low brain-to-body ratio (1.11, 1.07–1.15) and high head-to-length ratio (1.22, 1.19–1.26), corresponding with absolute risks of 22%, 10% and 19%, respectively). The effects were slightly lower when smoking had been quit during the first trimester. Similar effects were seen for the body size variables and low birth weight. Preterm birth was not associated with smoking only during first trimester.ConclusionsMaternal smoking, independent of smoking duration during pregnancy, was associated with abnormal body proportions resulting from larger reduction of length and head circumference in comparison to weight. The effects of having quit smoking during the first trimester and having continued smoking after the first trimester were similar, suggesting the importance of early pregnancy as a sensitive exposure window.
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Radwan, Mohsen Salem, Hosam E. Saleh, Youssef Ahmed Attai, and Mohamed Salah Elsherbiny. "On Heat Transfer enhancement in Diesel Engine Cylinder Head Using γ-Al2O3/water nanofluid with different nanoparticle sizes." Advances in Mechanical Engineering 12, no. 1 (January 2020): 168781401989750. http://dx.doi.org/10.1177/1687814019897507.
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In the current work, an experimental investigation of γ-Al2O3/water characteristics nanofluid was performed for convective cooling of engine cylinder head for fully developed turbulent regime. Nanoparticles of different sizes were mixed in distilled water with constant volume fraction of 1% through the experiments. The cylinder head was simulated as a rectangular duct, of an aspect ratio of 0.8, with a cast iron test specimen from actual cylinder head of diesel engine. The effect of different nanoparticle sizes (30, 100, and 150 nm), bulk temperature (60°C, 70°C, and 80°C), and flow velocity (1, 1.5 and 2 m/s) were investigated at variable heat fluxes. The experimental results revealed that the obtained enhancement of convective heat transfer coefficient is inversely proportional to both nanoparticle diameter and bulk temperature and directly proportional to the coolant flow velocity. Also, the highest achieved enhancement over the pure base fluid in heat transfer coefficient is 88.74% at 30 nm particle size. The γ-Al2O3/water nanofluid showed promising results for intensive study with different operating conditions.
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Rao, Xiaodong, Canchao Yang, and Wei Liang. "Comparison of head size and bite force in two sympatric munia species." Avian Biology Research 14, no. 3 (July 5, 2021): 98–102. http://dx.doi.org/10.1177/17581559211028403.
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Brain size is a key factor determining the performance and fitness of an organism; birds with relatively larger brains might have advantages in the utilization of resources and dispersal. Bite force is another important indicator of fitness, and plays an essential role in intra- and inter-specific competition. In this study, a comparative analysis was conducted on the head size and bite force of the two sister species, the white-rumped munia ( Lonchura striata) and scaly-breasted munia ( L. punctulata) that differ in distribution range. The results showed that the scaly-breasted munia, which has a wider distribution range, had a significantly larger head size than that of the white-rumped munia. In addition, scaly-breasted munias had a greater bite force; however, the difference was not significant. One possible explanation could be that the smaller head to body ratio in scaly-breasted munias reduced their bite-force slightly. Further, this finding could be attributed to the fact that similar food resources and foraging habitats of the two species lead to a similar bite force. Our study supported the argument that head size, rather than bite force, plays a more important role in the dispersal and evolutionary adaptation of birds.
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Farder-Gomes, C. F., M. A. Oliveira, P. L. Gonçalves, L. M. Gontijo, J. C. Zanuncio, M. A. L. Bragança, and E. M. Pires. "Reproductive ecology of phorid parasitoids in relation to the head size of leaf-cutting ants Atta sexdens Forel." Bulletin of Entomological Research 107, no. 4 (December 1, 2016): 487–92. http://dx.doi.org/10.1017/s0007485316001073.
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AbstractThe leaf-cutting ant Atta sexdens Forel (Hymenoptera: Formicidae) is one of the most damaging agricultural pests in the Neotropics. Management strategies predominantly rely on the use of general insecticides. What is needed are more species-specific and environmentally friendly options. Parasitioids such as phorid flies (Diptera: Phoridae) may be one such option, but a greater understanding of the ecology of the flies and their ant hosts is essential to devise biological control strategies. Here we report parasitism rates, ant host size, parasitoid abundance per host and resultant sex ratios of two phorid species Apocephalus attophilus Borgmeier and Eibesfeldtphora tonhascai Brown parasitizing A.sexdens. The two species achieved parasitism rates of 1.48 and 1.46%, respectively and the pupal period was 14.7 ± 1.1 days and 22.1 ± 2.8 days, respectively. There was no significant difference between the head capsule width of ants parasitized by either A. attophilus or E. tonhascai. Likewise, there was no significant effect between the head capsule width of parasitized and unparasitized ants for both species. A significant positive correlation was found between the head capsule width of the parasitized ants and the number of adult parasitoids A. attophilus emerged. Ants parasitized by E. tonhascai survived significantly longer than those parasitized by A. attophilus. There was no significant effect of ant head width on the sex ratio of the offspring of either parasitoid species and no significant difference in the sex ratio (male: female) of their offspring. In summary, these data addressed here are important steps when considering natural enemies for biological control. Studying survival of the parasitized ants, parasitoid offspring sex ratio and host size preference allows for a better understanding of ant natural biological control in the field and can help in rearing of A. attophilus and E. tonhascai in laboratory.
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ITO, YOICHI, FLORENCE NAAIM-BOUVET, KOUICHI NISHIMURA, HERVÉ BELLOT, EMMANUEL THIBERT, XAVIER RAVANAT, and FIRMIN FONTAINE. "Measurement of snow particle size and velocity in avalanche powder clouds." Journal of Glaciology 63, no. 238 (January 23, 2017): 249–57. http://dx.doi.org/10.1017/jog.2016.130.
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ABSTRACTParticle size, particle speed and airflow speed have been measured in the powder snow clouds of avalanches to investigate the suspension and transportation processes of snow particles. The avalanches were artificially triggered at the Lautaret full-scale avalanche test-site (French Alps) where an ultrasonic anemometer and a snow particle counter were setup in an avalanche track for measurements. Relatively large particles were observed during passage of the avalanche head and then the size of the particles slightly decreased as the core of the avalanche passed the measurement station. The particle size distribution was well fitted by a gamma distribution function. A condition for suspension of particles within the cloud based on the ratio of vertical velocity fluctuation to particle settling velocity suggests that the large particles near the avalanche head are not lifted up by turbulent diffusion, but rather ejected by a process involving collisions between the avalanche flow and the rough snow surface. Particle speeds were lower than the airflow speed when large particles were present in the powder cloud.
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Graves, A. B., J. A. Mortimer, E. B. Larson, A. Wenzlow, J. D. Bowen, and W. C. McCormick. "Head Circumference as a Measure of Cognitive Reserve." British Journal of Psychiatry 169, no. 1 (July 1996): 86–92. http://dx.doi.org/10.1192/bjp.169.1.86.
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BackgroundRecent studies suggest that larger brain size may offer some protection against the clinical manifestations of Alzheimer's disease. However, this association has not been investigated in population-based studies.MethodThe relationship between head circumference, a measure of premorbid brain size, and score on the Cognitive Abilities Screening Instrument (CASI) was studied in a population of 1985 Japanese–Americans aged 65+ living in King County, Washington, USA.ResultsAfter adjusting for age, sex and education, head circumference was positively associated with CASI score (b=3.8, 95% CI: 2.2, 5.4; P=0.0000), but not with diagnosis of probable AD (odds ratio=0.87, 95% CI: 0.33, 1.87). When the data were stratified by AD status, no association was seen among controls (b=1.6, 95% CI: – 1.7, 5.1; P=0.4), whereas a strong effect was present among cases (b=35.3, 95% CI: 12.2, 58.4: P=0.006).ConclusionsThese results suggest that persons with AD with smaller head circumference either had the disease longer or progressed more rapidly than those with larger head circumference. Improvement in environmental factors in prenatal and early life that partially determine completed brain/head size may have consequences for the late-life expression of Alzheimer's disease in vulnerable individuals.
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Vázquez, José Antonio, Araceli Menduíña, Margarita Nogueira, Ana I. Durán, Noelia Sanz, and Jesus Valcarcel. "Optimal Production of Protein Hydrolysates from Monkfish By-Products: Chemical Features and Associated Biological Activities." Molecules 25, no. 18 (September 6, 2020): 4068. http://dx.doi.org/10.3390/molecules25184068.
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The aim of this work was the recovery of protein substrates from monkfish waste (heads and viscera) generated in the on-board processing of this species. Initially, the effect of pH, temperature, and protease concentration was studied on mixtures of a 1:1 ratio (w/v) of monkfish heads/water. The optimal conditions of proteolytic digestion were established at 57.4 °C, pH 8.31, [Alcalase] = 0.05% (v/w) for 3 h of hydrolysis. Later on, a set of hydrolysis at 5L-pH-stat reactor were run under the aforementioned conditions, confirming the validity of the optimization studies for the head and viscera of monkfish. Regarding the chemical properties of the fish protein hydrolysates (FPH), the yield of digestion was higher than 90% in both cases and the degrees of hydrolysis and the soluble protein content were not especially large (<20% and <45 g/L, respectively). In vitro digestibility was higher than 90% and the percentage of essential amino acids ranged from 40 to 42%. Antioxidant activities were higher in viscera FPH, and antihypertensive ability was superior in head FPH. The values of number average molecular weights (Mn) of monkfish hydrolysates were 600 Da in the viscera and 947 Da in the head. The peptide size distribution, obtained by size-exclusion chromatography, indicated that the largest presence of peptides below 1000 Da and 200 Da was observed in the viscera FPH.
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Qian, Lijuan, Jingqi Liu, Hongchuan Cong, Fang Zhou, and Fubing Bao. "A Numerical Investigation on the Collision Behavior of Unequal-Sized Micro-Nano Droplets." Nanomaterials 10, no. 9 (September 3, 2020): 1746. http://dx.doi.org/10.3390/nano10091746.
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Micro-nano droplet collisions are fundamental phenomena in the applications of nanocoating, nano spray, and microfluidics. Detailed investigations of the process of the droplet collisions under higher Weber are still lacking when compared with previous research studies under a low Weber number below 120. Collision dynamics of unequal-sized micro-nano droplets are simulated by a coupled level-set and volume of fluid (CLSVOF) method with adaptive mesh refinement (AMR). The effects of the size ratio (from 0.25 to 0.75) and different initial collision velocities on the head-on collision process of two unequal-sized droplets at We = 210 are studied. Complex droplets will form the filament structure and break up with satellite droplets under higher Weber. The filament structure is easier to disengage from the complex droplet as the size ratio increases. The surface energy converting from kinetic energy increases with the size ratio, which promotes a better spreading effect. When two droplets keep the constant relative velocity, the motion tendency of the droplets after the collision is mainly dominated by the large droplet. On one hand, compared with binary equal-sized droplet collisions, a hole-like structure can be observed more clearly since the initial velocity of a large droplet decreases in the deformation process of binary unequal-sized droplets. On the other hand, the rim spreads outward as the initial velocity of the larger droplet increases, which leads to its thickening.
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Lee, Jiyun, and Seung-Jun Choi. "Influence of Blending of Nonionic Emulsifiers Having Various Hydrophilic Head Sizes on Lipid Oxidation: Investigation of Antioxidant Polarity—Interfacial Characteristics Relationship." Antioxidants 10, no. 6 (May 31, 2021): 886. http://dx.doi.org/10.3390/antiox10060886.
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The purpose of this study was to deliver insights into the effect of interfacial composition and antioxidant polarity on the lipid oxidation of emulsions. Emulsions were created using blends of nonionic ethoxylated fatty acid alcohol surfactants with different hydrophilic head sizes, and lipophilic (TBHQ) and amphiphilic (lauryl gallate) antioxidants were incorporated into the emulsions. At the same surfactant concentration, emulsion stabilized with surfactant with a smaller hydrophilic head was more susceptible to lipid oxidation than that stabilized with surfactant with a larger hydrophilic head. When surfactants with a similar hydrophilic head size were used, lipid oxidation in emulsion containing more surfactant was slightly faster than that containing less surfactant. When emulsions were created with a 1:1 molar ratio mixture of surfactants with small and large hydrophilic heads, surfactant concentration (1.00 and 2.932 mM) had little effect on lipid peroxide generation rate. However, the concentration of thiobarbituric acid-reactive substances (TBARSs) in the emulsion prepared at 1.00 mM increased faster than that prepared at 2.93 mM. Alteration of interfacial composition and surfactant concentration did not affect antioxidant ability, regardless of antioxidant polarity, to inhibit lipid peroxide generation. However, the ability of lauryl gallate and TBHQ to prevent TBARS generation was elevated by mixing surfactants with small and large hydrophilic heads and by decreasing surfactant concentration. In most emulsions, lauryl gallate showed a more effective antioxidant ability than TBHQ.
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Stoffella, Peter J., and Mike F. Fleming. "Plant Population Influences Yield Variability of Cabbage." Journal of the American Society for Horticultural Science 115, no. 5 (September 1990): 708–11. http://dx.doi.org/10.21273/jashs.115.5.708.
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Cabbage [Brassica oleracea L. (Capitata Group) cv. Bravo] transplants were grown on raised beds at Fort Pierce, Fla., during Fall 1987 and 1988. Plants were spaced at 8, 15, 23, 30, and 38 cm within rows or populations equivalent to 123,000, 61,500, 41,000, 30,800, and 24,600 plants/ha. Individual root weights, total plant weights, and core length increased linearly as within-row spacing (WRS) increased in both experiments. Untrimmed head weights, trimmed head weights, head height, head width, and core width increased quadratically as WRS increased in both experiments. Head shape and core index did not differ among WRS in either experiment, except for a quadratic increase in the head height: bead width ratio (head shape) as WRS increased in the 1988 experiment. Coefficients of variability (cv) for most measured variables decreased as WRS increased, indicating a reduction in plant-to-plant variation. Optimum marketable cabbage head size (>1 kg) and lower plant-to-plant variation (cv < 20%) were obtained at WRS of 23 cm or wider. However, trimmed cabbage yields decreased linearly as WRS increased in both experiments. In this study, a lower plant population (WRS > 23 cm) was more conducive to a once-over cabbage harvest since plant-to-plant variation in head size and other yield and quality characteristics was reduced.
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Hook, Kristin A., Qixin Yang, Leonard Campanello, Wolfgang Losert, and Heidi S. Fisher. "The social shape of sperm: using an integrative machine-learning approach to examine sperm ultrastructure and collective motility." Proceedings of the Royal Society B: Biological Sciences 288, no. 1959 (September 22, 2021): 20211553. http://dx.doi.org/10.1098/rspb.2021.1553.
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Sperm is one of the most morphologically diverse cell types in nature, yet they also exhibit remarkable behavioural variation, including the formation of collective groups of cells that swim together for motility or transport through the female reproductive tract. Here, we take advantage of natural variation in sperm traits observed across Peromyscus mice to test the hypothesis that the morphology of the sperm head influences their sperm aggregation behaviour. Using both manual and automated morphometric approaches to quantify their complex shapes, and then statistical modelling and machine learning to analyse their features, we show that the aspect ratio of the sperm head is the most distinguishing morphological trait and statistically associates with collective sperm movements obtained from in vitro observations. We then successfully use neural network analysis to predict the size of sperm aggregates from sperm head morphology and show that species with relatively wider sperm heads form larger aggregates, which is consistent with the theoretical prediction that an adhesive region around the equatorial region of the sperm head mediates these unique gametic interactions. Together these findings advance our understanding of how even subtle variation in sperm design can drive differences in sperm function and performance.
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Gracceva, Giulia, Marco Bologna, Luca Luiselli, and Pierluigi Bombi. "Do demographic aspects of neighbouring lizard populations differ? A case study with the common wall lizard, Podarcis muralis." Amphibia-Reptilia 29, no. 3 (2008): 443–48. http://dx.doi.org/10.1163/156853808785111959.
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Abstract Demographic and morphological aspects of two nearby subpopulations of the common wall lizard (Podarcis muralis) were studied, by a capture-mark-recapture procedure, at an archaeological site in the surroundings of Rome, central Italy. In both sites, the births peak was observed in September. Adult sex-ratio was skewed towards males in one subpopulation, but was close to equality in the other. Morphological characteristics were consistent in the two sites, with males always exhibiting larger snout-vent-length and head size. Population size and density, computed by a Jolly-Seber index applied by using POPAN model revealed differences between subpopulations, with lizard density being much higher in the site with higher habitat heterogeneity and shelter availability. Tail condition was similar between sites. The general implications of these data are discussed.
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Musa, Taghreed Abd-Almahdee, Marwah Abdullah Shlash, and Hayder Sami Mohammed. "The effect of cutoff angle on the head pressure underneath dams constructed on soils having rectangular void." Open Engineering 12, no. 1 (January 1, 2022): 495–500. http://dx.doi.org/10.1515/eng-2022-0026.
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Abstract In this research, a hydraulic model is used to find the effect of the cutoff angle and dimensions of the void in the soil on the head pressure and leakage under the dam, and finding the best angle and size of the void will have a positive effect. The model was designed with a cutoff that can be moved in three angles (45°, 90° and 135°) in the center of the dam and three ratios of void dimensions (width of the void (W)/the dam width (b) = 0, 0.34 and 0.69) were taken. Head pressure was measured using a piezometer installed in the front of the model. When the flow reached the balance, leakage and pressure head were measured. From the results, it was observed that the lowest head pressure value occurs when the angle is 90° and the void ratio is 0.69. The principles of dimensional analysis and non-linear regression by using IBM SPSS 19 were used to find an empirical formula for the computation of the head pressure depending on the angle of the cutoff and the size of the void.
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Polinsky, Maria, and Lilla Magyar. "Headedness and the Lexicon: The Case of Verb-to-Noun Ratios." Languages 5, no. 1 (February 13, 2020): 9. http://dx.doi.org/10.3390/languages5010009.
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This paper takes a well-known observation as its starting point, that is, languages vary with respect to headedness, with the standard head-initial and head-final types well attested. Is there a connection between headedness and the size of a lexical class? Although this question seems quite straightforward, there are formidable methodological and theoretical challenges in addressing it. Building on initial results by several researchers, we refine our methodology and consider the proportion of nouns to simplex verbs (as opposed to light verb constructions) in a varied sample of 33 languages to evaluate the connection between headedness and the size of a lexical class. We demonstrate a robust correlation between this proportion and headedness. While the proportion of nouns in a lexicon is relatively stable, head-final/object-verb (OV)-type languages (e.g., Japanese or Hungarian) have a relatively small number of simplex verbs, whereas head-initial/verb-initial languages (e.g., Irish or Zapotec) have a considerably larger percentage of such verbs. The difference between the head-final and head-initial type is statistically significant. We, then, consider a subset of languages characterized as subject-verb-object (SVO) and show that this group is not uniform. Those SVO languages that have strong head-initial characteristics (as shown by the order of constituents in a set of phrases and word order alternations) are characterized by a relatively large proportion of lexical verbs. SVO languages that have strong head-final traits (e.g., Mandarin Chinese) pattern with head-final languages, and a small subset of SVO languages are genuinely in the middle (e.g., English, Russian). We offer a tentative explanation for this headedness asymmetry, couched in terms of informativity and parsing principles, and discuss additional evidence in support of our account. All told, the fewer simplex verbs in head-final/OV-type languages is an adaptation in response to their particular pattern of headedness. The object-verb/verb-object (OV/VO) difference with respect to noun/verb ratios also reveals itself in SVO languages; some languages, Chinese and Latin among them, show a strongly OV ratio, whereas others, such as Romance or Bantu, are VO-like in their noun/verb ratios. The proportion of nouns to verbs thus emerges as a new linguistic characteristic that is correlated with headedness.
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Gao, Lei, and Qun Chen. "A Cluster Algorithm for Wireless Sensor Networks Based on Energy Efficiency." Applied Mechanics and Materials 785 (August 2015): 744–50. http://dx.doi.org/10.4028/www.scientific.net/amm.785.744.
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In order to solve the energy limited problem of sensor nodes in the wireless sensor networks (WSN), a fast clustering algorithm based on energy efficiency for wire1ess sensor networks is presented in this paper. In the system initialization phase, the deployment region is divided into several clusters rapidly. The energy consumption ratio and degree of the node are chosen as the selection criterion for the cluster head. Re-election of the cluster head node at this time became a local trigger behavior. Because of the range of the re-election is within the cluster, which greatly reduces the complexity and computational load to re-elect the cluster head node. Theoretical analysis indicates that the timing complexity of the clustering algorithm is O(1), which shows that the algorithm overhead is small and has nothing to do with the network size n. Simulation results show that clustering algorithm based on energy efficiency can provide better load balancing of cluster heads and less protocol overhead. Clustering algorithm based on energy efficiency can reduce energy consumption and prolong the network lifetime compared with LEACH protocol.
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Saghi, Hassan, and Joško Parunov. "Hydrodynamic Force of Resistance of Tourist Underwater Vehicle’s Bare Hull with Diff erent Heads using OpenFOAM." Naše more 70, no. 1 (March 2023): 11–22. http://dx.doi.org/10.17818/nm/2023/1.3.
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Power reduction is the central goal to maximize cruising duration of tourist underwater vehicles (UV) that can be achieved by shaping the hull. So, in this paper, hydrodynamic force of resistance of the tourist UV’s bare hull is analysed. A numerical model based on Computational Fluid Dynamics in OpenFOAM is developed to simulate the longitudinal movement of an UV in a viscous and incompressible fluid for the infinite water depth. Three head geometries, including both spherical heads (S-S), spherical bow and elliptical stern head (S-E), and UV with both elliptical heads (E-E) are compared. At the first step, the effects of the length-to-diameter ratio and forward speed is studied for the S-S UV. The mesh size is calibrated using Grid Convergence Index, provided by ASME, while the model validation is based on the results for cube and sphere as well as by comparison with resistance coefficient of a SUBOFF bare hull. S-E and E-E UVs are then analysed for typical length-to-diameter ratio, comparing their force of resistance to the S-S type. The elongated elliptical heads are in many cases found favourable compared to the spherical heads. The results of this study may be useful for the conceptual design of tourist UV and for verification of the complex numerical models that are necessary to account for the influence of appendages on the force of resistance of such innovative UV.
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Fujiwara, T., Shinya Tsukamoto, and M. Miyagawa. "Analysis of the Grinding Mechanism with Wheel Head Oscillating Type CNC Crankshaft Pin Grinder." Key Engineering Materials 291-292 (August 2005): 163–70. http://dx.doi.org/10.4028/www.scientific.net/kem.291-292.163.
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In this study, the crankshaft pin grinding mechanism, which is carried out with wheel head oscillating type CNC crankshaft pin grinder, is theoretically analyzed. In order to maintain grinding process, the pin rotates and also rocks along wheel working surface, because the wheel head oscillates with journal rotation. Then, it is made clear that cylindrical plunge grinding process progresses in the pin grinding process for the first time. Therefore, grinding speed ratio, which is defined as ratio of substantial pin surface speed to wheel surface speed, is firstly formulated. Secondly, undeformed chip size generated by a grain is estimated with the grinding velocity ratio. Finally, the grinding performance is predicted with experimental equations, which obtained previous study. By this simulation, it is made clear that dimensional accuracy and also surface roughness vary on whole of the pin surface with constant journal rotation grinding method. On the contrary, deviations of both the dimensional accuracy and the surface roughness are reduced with controlled speed ratio grinding method, in which journal rotation speed is adequately controlled.
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Kleinhenz, Matthew D., and Annette Wszelaki. "Yield and Relationships among Head Traits in Cabbage as Influenced by Planting Date and Cultivar. I. Fresh Market." HortScience 38, no. 7 (December 2003): 1349–54. http://dx.doi.org/10.21273/hortsci.38.7.1349.
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Yield and relationships among head traits were recorded in order to better understand the effects of planting date and cultivar selection on crop quality characteristics and to help increase the efficiency of cultivar development, evaluation, and selection. A total of seven cultivars of fresh market-type cabbage (Brassica oleracea L., Capitata Group) were planted in May and June of 1999 and 2000 at the OARDC Vegetable Crops Research Branch in Fremont, Ohio. Total and marketable yield, head traits (e.g., size, weight, density), and core dimensions were recorded at harvest. Main effects of year (Y), planting date (PD), and cultivar (C) and the Y × C interaction significantly affected seven to 10 of 10 head and core traits. However, the PD × C interaction was significant for head density, the ratio of head polar and equatorial diameter, and core base width. The Y × PD interaction was significant for six of 10 head and core traits. May planting tended to result in greater yield and larger, heavier heads with greater polar/equatorial diameter values relative to June planting. However, head density was unaffected by planting date. The number of head and core traits affected by planting date differed among cultivars. For example, six of 10 head and core traits were significantly affected by planting date in `Cheers' and `DPSX315' while one trait was affected by planting date in `SuperElite Hybrid'. The weight of numerous, individual, market-ready, trimmed heads showed a strong (avg. R2 value = 0.92) quadratic relationship to average head diameter. These data suggest that large-scale germplasm evaluations may benefit by including multiple plantings, as head weight, volume, diameter, and shape were affected by planting date, possibly due to variation in temperature and rainfall patterns. The data also suggest that routine measurement of numerous head traits in the same evaluations may be unnecessary, as selected traits (e.g., diameter and weight, head volume, and core volume) were strongly related.
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Viraj Pradhan and Karambelkar V H. "To Evaluate Optic Nerve Head Changes In Patients With Primary Open Angle Glaucoma." International Journal of Research in Pharmaceutical Sciences 11, no. 3 (July 30, 2020): 4463–67. http://dx.doi.org/10.26452/ijrps.v11i3.2669.
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The early discovery of optic nerve head changes via careful assessment prompts initial finding and the board of essential open point glaucoma. The current examination was attempted to break down to the optic nerve head in patients of open point glaucoma regarding visual field defects.110 eyes of 60 patients were concentrated in this cross-sectional investigation. The mean age of the patients was 58.26±10.44 years, with 30 males and 30 females. 15% of the patients were suffering from hypertension. The mean IOP among the eyes was 18.63 ±4.17 mm of Hg. The mean vertical C/D ratio was 0.61 ±0.12. 89.09% of patients had a medium disc size. The R/D ratio among patients showed that majority of eyes having RD ratio of 0.01-0.1 (30.91%). HPA grades showed that 32.72% had severe visual field defects. 97.30% of eyes had a contiguous visual loss as compared to noncontiguous (2.70%). The nasal field was mostly affected by 51.35%. DDLS has a stronger correlation with Mean Defect than Vertical C/D ratio and with HPA classification than the Vertical C/D ratio. DDLS to be a simple, brisk, modest and precise strategy to record ONH harm. It seems, by all accounts, to be better than the C/D proportion for optic plate assessment.
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Wei, Yi-Kun, Zhe-Hong Li, and Yi-Fan Zhang. "Simulations of coalescence of two colliding liquid drops using lattice Boltzmann method." Journal of Computational Multiphase Flows 9, no. 4 (September 21, 2017): 147–56. http://dx.doi.org/10.1177/1757482x17716044.
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In this paper, two-dimensional numerical simulations of the head-on and off-center binary collision of liquid drops are carried out using lattice Boltzmann method. The coalescence process of drops colliding is freely captured, regardless of tracking equations and drops model. Special attention is paid to investigate the effect of the Weber number, impact velocity, drop size ratio on the coalescence process. The research results demonstrate that numerical results of lattice Boltzmann method are in agreement with qualitatively experimental data in the same Weber number. It is also noted that the first oscillation period is invariably shorter than the second period, regardless of the Weber number. It is further found that variation of the first period of oscillation in off-center collision of two equal-size drops as function of Weber number are higher than the variation of the first period of oscillation in head-on collision of two equal-size drops in the same Weber number.
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Kramer, Robin S. S. "Within-person variability in men’s facial width-to-height ratio." PeerJ 4 (March 10, 2016): e1801. http://dx.doi.org/10.7717/peerj.1801.
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Background.In recent years, researchers have investigated the relationship between facial width-to-height ratio (FWHR) and a variety of threat and dominance behaviours. The majority of methods involved measuring FWHR from 2D photographs of faces. However, individuals can vary dramatically in their appearance across images, which poses an obvious problem for reliable FWHR measurement.Methods.I compared the effect sizes due to the differences between images taken with unconstrained camera parameters (Studies 1 and 2) or varied facial expressions (Study 3) to the effect size due to identity, i.e., the differences between people. In Study 1, images of Hollywood actors were collected from film screenshots, providing the least amount of experimental control. In Study 2, controlled photographs, which only varied in focal length and distance to camera, were analysed. In Study 3, images of different facial expressions, taken in controlled conditions, were measured.Results.Analyses revealed that simply varying the focal length and distance between the camera and face had a relatively small effect on FWHR, and therefore may prove less of a problem if uncontrolled in study designs. In contrast, when all camera parameters (including the camera itself) are allowed to vary, the effect size due to identity was greater than the effect of image selection, but the ranking of the identities was significantly altered by the particular image used. Finally, I found significant changes to FWHR when people posed with four of seven emotional expressions in comparison with neutral, and the effect size due to expression was larger than differences due to identity.Discussion.The results of these three studies demonstrate that even when head pose is limited to forward facing, changes to the camera parameters and a person’s facial expression have sizable effects on FWHR measurement. Therefore, analysing images that fail to constrain some of these variables can lead to noisy and unreliable results, but also relationships caused by previously unconsidered confounds.
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Bisconti, Michelangelo, Luca Pellegrino, and Giorgio Carnevale. "Evolution of gigantism in right and bowhead whales (Cetacea: Mysticeti: Balaenidae)." Biological Journal of the Linnean Society 134, no. 2 (July 18, 2021): 498–524. http://dx.doi.org/10.1093/biolinnean/blab086.
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Abstract The evolution of gigantic body size represents a key to understand the ecological role of baleen whales in oceanic ecosystems. Many efforts have been devoted to the formulation of equations relating different body parts to total body length and mass in living and fossil mysticetes, mainly focusing on balaenopterid and balaenopterid-like mysticetes. Right whales (family Balaenidae) have a unique head-to-body length ratio, suggesting that their body proportions cannot be predicted effectively using equations based primarily on non-balaenid mysticetes. A new morphometric dataset of living and fossil balaenids is provided herein, and new regression equations allow one to predict the body length and mass of extinct species based on the expected head-to-body length ratio of extant balaenids. The reconstructed values are mapped on a new phylogenetic analysis of the Balaenidae, inferring body size and mass at ancestral nodes. The variations of body size and mass in Balaenidae since the early Miocene are reconstructed, revealing that: (1) a reduction in total body length occurred in the early Pliocene; (2) the origin of the gigantic body size in the bowhead whale (Balaena mysticetus) is probably related to invasion of the Arctic Ocean in the last 3 Myr; and (3) the origin of the gigantic body size in the right whales (genus Eubalaena) occurred since the latest Miocene, probably concomitant with pulses of nutrients sustaining large zooplankton populations. We suggest that the evolution of gigantism in Balaenidae occurred independently in two lineages and, probably, in response to different palaeoenvironmental drivers.
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MASUD, AHMAD IJAZ, QAISER MAHMOOD, and NASREEN SIDDIQUE. "UNRESECTABLE HEAD AND NECK CARCINOMAS." Professional Medical Journal 14, no. 01 (March 10, 2007): 111–19. http://dx.doi.org/10.29309/tpmj/2007.14.01.3634.
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Introduction: Cancers of the head and neck are estimated to be the most prevalent cancers in the world. Data from various cancer centers of Pakistan reveal that epithelial head and neck cancer is one of the most frequent cancers varying from 12 to 25% of the total new patients seenannually. Objectives: To see the effect of concomitant chemo-radiotherapy on the survival of patient, to assess the toxicity of different treatment arms and the effect of age, sex and bulk or tumour on survival and compare the literature. Setting: Radiotherapy Department, Nishtar Hospital, Multan. Duration: 2 years. Material and Methods: Sample Size: 200 patients. Results: Out of 130 patients, 83 were males and theremaining 47 were females. The male to female ratio being 1.8:1. The mean age of the patients included in the study was 52 years, range being 22-80 years. The patients of head and neck cancer in the trial had different sites of involvement. In the trial the patients presented with various symptoms such as pain, swelling, ulcer, bleeding, dysphagia, dyspnea, hoarseness of voice and nasal obstruction etc. No patient had early stage disease. All the patients in the trial had the experience of nausea and vomiting, it was more marked in patients having radiotherapy; either alone or in concomitant with chemotherapy. The patients having concomitant chemo-radiotherapy i.e. group-C also had diarrhoea as a side effect. The effect on the liver function test was more pronounced in patients of group-A. The renal function was seen to alter more in patients receiving chemotherapy with cisplatin, whether as induction or as a concomitant to radiotherapy. Conclusion: Concomitant chemo-radiotherapy in locally advanced, unresectable head and neck carcinoma is statistically superior to induction chemotherapy followed by radiotherapy and the standard radiotherapy alone.
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Rinaldi, M., M. C. Facchini, S. Decesari, C. Carbone, E. Finessi, M. Mircea, S. Fuzzi, et al. "Coastal and open ocean aerosol characteristics: investigating the representativeness of coastal aerosol sampling over the North-East Atlantic Ocean." Atmospheric Chemistry and Physics Discussions 8, no. 6 (November 5, 2008): 19035–62. http://dx.doi.org/10.5194/acpd-8-19035-2008.
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Abstract. In order to achieve a better understanding of the modifications of the physical and chemical properties of marine aerosol particles during transport from offshore to the coast, size distribution and chemical composition were measured concurrently in clean air masses over the open North Atlantic Ocean and at an Irish coastal site. Open ocean sampling was performed on board the oceanographic vessel Celtic Explorer sailing 100–300 km off the Irish west coast, while coastal measurements were performed at the Mace Head GAW station. The experiment took place between 11 June and 6 July 2006, during the period of phytoplankton bloom. The number size distribution and size-resolved chemical composition of coastal and open ocean samples were very similar, indicating homogeneous physical and chemical aerosol properties over a wide region in the marine boundary layer. The results also show that submicron chemical and physical aerosol properties measured at the coastal Mace Head Atmospheric Research Station were not unduly influenced by coastal artefacts and are thus representative of open water properties. Greater differences between the coastal site and the open ocean were observed for the aerosol supermicron sea spray components; this could be due to a variety of reasons, ranging from higher local wind speeds at the coastal site over the comparison period, to differences in sampling heights and increased local surf-zone production. Evidence of ageing processes was observed: at the costal site the ratio between non-sea-salt sulphate and methanesulphonic acid was higher, and the aerosol water soluble organic compounds were more oxidized than in the open ocean.
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Kumarasamy, Chellan, Vaibhav Tiwary, Krishnan Sunil, Deepa Suresh, Sameep Shetty, Gothandam Kodiveri Muthukaliannan, Siddhartha Baxi, and Rama Jayaraj. "Prognostic Utility of Platelet–Lymphocyte Ratio, Neutrophil–Lymphocyte Ratio and Monocyte–Lymphocyte Ratio in Head and Neck Cancers: A Detailed PRISMA Compliant Systematic Review and Meta-Analysis." Cancers 13, no. 16 (August 19, 2021): 4166. http://dx.doi.org/10.3390/cancers13164166.
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Inflammation plays a major role in cancer development and progression and has the potential to be used as a prognostic marker in cancer. Previous studies have attempted to evaluate Platelet-to-lymphocyte ratio (PLR), neutrophil–lymphocyte ratio (NLR) or monocyte–lymphocyte ratio (MLR) as indicators of inflammation/prognostic markers in cancer, but there is no common consensus on their application in clinical practice. The aim of this systematic review and meta-analysis is to (a) assess the prognostic efficacy of all three prognostic markers in comparison to each other and (b) investigate the prognostic potential of these three markers in HNC. The study followed PRISMA guidelines, with the literature being collated from multiple bibliographic databases. Preliminary and secondary screening were carried out using stringent inclusion/exclusion criteria. Meta-analysis was carried out on selected studies using CMA software and HR as the pooled effect size metric. A total of 49 studies were included in the study. The pooled HR values of PLR, NLR and MLR indicated that they were significantly correlated with poorer OS. The pooled effect estimates for PLR, NLR and MLR were 1.461 (95% CI 1.329–1.674), 1.639 (95% CI 1.429–1.880) and 1.002 (95% CI 0.720–1.396), respectively. Significant between-study heterogeneity was observed in the meta-analysis of all three. The results of this study suggest that PLR, NLR and MLR ratios can be powerful prognostic markers in head and neck cancers that can guide treatment. Further evidence from large-scale clinical studies on patient cohorts are required before they can be incorporated as a part of the clinical method. PROSPERO Registration ID: CRD42019121008
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Funakoshi, Tadanao, Kozo Furushima, Azusa Miyamoto, Hiroshi Kusano, Yukio Horiuchi, and Yoshiyasu Itoh. "Predictors of Unsuccessful Nonoperative Management of Capitellar Osteochondritis Dissecans." American Journal of Sports Medicine 47, no. 11 (July 26, 2019): 2691–98. http://dx.doi.org/10.1177/0363546519863349.
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Background: Osteochondritis dissecans of the humeral capitellum (capitellar OCD) is a common injury among adolescent throwing athletes. Some younger patients with incomplete maturity of the epiphysis and early-stage capitellar OCD are good candidates for nonoperative treatment. However, during initial examination, predicting the need for surgical treatment in patients with capitellar OCD is difficult. Purpose: To perform multivariate ordered logistic regression analysis of data obtained from patients’ medical records and images on initial examination and identify the predictors of unsuccessful nonoperative management of capitellar OCD. Study Design: Cohort study (prognosis); Level of evidence, 2. Methods: This study included 245 elbows with capitellar OCD (all male; mean age, 14 years [range, 10-27 years]). Patients were divided into 3 groups comprising 148 elbows requiring an immediate operation on initial examination, 48 requiring nonsurgical treatment, and 49 requiring an operation after nonoperative management. Baseline data and radiographic parameters, such as lesion location, lesion size, modified Minami classification, radial head size, skeletal age difference between both elbows on initial examination, lesion size on computed tomography, and staging on magnetic resonance imaging, were retrospectively reviewed. Univariate and multivariate ordered logistic regression analyses of spontaneous healing of the lesion were conducted. Results: Univariate logistic regression analysis showed that radial head enlargement and skeletal age difference were significantly associated with spontaneous healing. In multivariate ordered logistic regression analysis, radial head enlargement (anteroposterior and lateral) and skeletal age difference were significant predictors of lack of spontaneous healing (odds ratio [OR], 2.76, P =.025; OR, 7.92, P =.026; and OR, 1.84, P =.0089, respectively). Conclusion: To predict spontaneous healing in the moderate stage, plain radiographs would be important to evaluate radiocapitellar congruity and skeletal age. This study showed that preoperative radiographic findings of radial head enlargement and advanced skeletal age of the throwing side compared with that of the nonthrowing side were predictors of advanced-stage capitellar OCD. Despite several limitations, the statistical significance and correlations herein provide important information on preoperative surgical planning to surgeons.
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Marini, M., A. Massardo, A. Satta, and M. Geraci. "Low Area Ratio Aircraft Fuel Jet-Pump Performances With and Without Cavitation." Journal of Fluids Engineering 114, no. 4 (December 1, 1992): 626–31. http://dx.doi.org/10.1115/1.2910077.
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The experimental analysis performed on several small size low area ratio aircraft fuel jet pumps in JP4 is outlined. The variables investigated were area ratio, nozzle and throat diameters, nozzle and suction pressures. The experimental values of head ratio were compared to a one-dimensional theoretical prediction method previously found to be applicable to moderate and high area ratio pumps. The results show the necessity of making some modifications in the model at low flow coefficient values. Measured wall static pressures were also compared with the results of an axisymmetric finite difference turbulent calculation; the comparisons are generally in good agreement. The development of cavitation and related parameters were also investigated. In order to enhance cavitation resistance, which is particularly important in the field of aeronautics, some studies were carried out on two stage jet pumps. The results obtained are outlined and discussed.
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Min, Yong Ho, Chae Hoon Sohn, and Youngbin Yoon. "Thermoacoustic Stability Boundaries in the Model Combustion Chamber with a Gas-Centered Swirl Coaxial Injector." International Journal of Aerospace Engineering 2019 (November 19, 2019): 1–9. http://dx.doi.org/10.1155/2019/9232739.
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The stability of a combustion chamber with a gas-centered swirl coaxial injector is investigated over a wide range of operating conditions in the aspect of thermoacoustic instabilities. First, flame shapes induced by the injector are analyzed for various recess lengths from experimental results. The spreading angle and flame size are reduced as the recess length increases. And, as a stability criterion, the damping factor is introduced. The operating conditions are divided into 7 sets with 9 tests, and fuel mass flow is fixed in each set. Stability boundaries are identified in terms of damping factor for the 63 tests by experiments without external perturbations. The stability map for the self-excited instability is obtained and it reveals two unstable regions. One is located at low dynamic head ratio and the other one is at high dynamic head ratio. A stable region is found at moderate dynamic head ratios. Relative stability is evaluated by various flow parameters over a wide range of operating conditions in the combustion chamber with a gas-centered swirl coaxial injector.
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Nisa, Iffat Un, Anjum Tazeen, Sabar Butt, Mehreen Fatima, and Syed Amir Gilani. "Comparison of Head Circumference and Abdominal Circumference Ratio in Normotensive and patients with Pregnancy Induced Hypertensive Disorders after 28 weeks of gestation." Pakistan Journal of Medical and Health Sciences 15, no. 8 (August 26, 2021): 1931–34. http://dx.doi.org/10.53350/pjmhs211581931.
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Background: Hypertensive disorders are an important medical problem of gestation. Hypertensive disorders of pregnancy (HDP) are a significant cause for maternal and fetal morbidity as well as mortality. Intrauterine growth retardation (IUGR) commonly describes the condition of fetus whose size or growth is subnormal. IUGR fetus is frequently described as symmetrical and asymmetrical IUGR in term of their body proportions. Asymmetric growth retardation is typically linked to uteroplacental inadequacy. Hypertension is one of the maternal causes of placental insufficiency. Aim: To compare head circumference and abdominal circumference ratio in normotensive and patients with pregnancy induced hypertensive disorders after 28 weeks of gestation. Methodology: A cross sectional analytical study was carried on 113 pregnant females in which 57 women were normotensive and 56 women were hypertensive. All individuals were scanned by two- dimensional ultrasound following 28 weeks of pregnancy to evaluate sonographic parameters HC and AC. The HC/AC ratio was estimated by dividing head circumference with abdominal circumference. Results: Out of 57 normotensive patients 27 (36.48%) fetuses were diagnosed with IUGR having HC/AC ratio more than 1, while 30 had normal HC/AC ratio. In 56 hypertensive patients 47(63.51%) fetuses were diagnosed with IUGR having HC/AC ratio greater than 1, however 9(23.07%) fetuses had HC/AC ratio within normal range. So out of total 113 patients, 74 fetuses were found with IUGR while 39 fetuses had HC/AC ratio within normal ranges. Our study found that a cut off value of ≥ 1.0974 for HC/AC ratio could be used as diagnostic parameter in predicting IUGR. Conclusion: HC/AC ratio is a useful parameter for the detection of IUGR. Keywords: Head Circumference, Abdominal Circumference, Intra Uterine Growth Retardation
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Amin, Muhammad Nasir, Mudassir Iqbal, Babatunde Abiodun Salami, Arshad Jamal, Kaffayatullah Khan, Abdullah Mohammad Abu-Arab, Qasem Mohammed Sultan Al-Ahmad, and Muhammad Imran. "Predicting Bond Strength between FRP Rebars and Concrete by Deploying Gene Expression Programming Model." Polymers 14, no. 11 (May 25, 2022): 2145. http://dx.doi.org/10.3390/polym14112145.
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Rebars made of fiber-reinforced plastic (FRP) might be the future reinforcing material, replacing mild steel rebars, which are prone to corrosion. The bond characteristics of FRP rebars differ from those of mild steel rebars due to their different stress-strain behavior than mild steel. As a result, determining the bond strength (BS) qualities of FRP rebars is critical. In this work, BS data for FRP rebars was investigated, utilizing non-linear capabilities of gene expression programming (GEP) on 273 samples. The BS of FRP and concrete was considered a function of bar surface (Bs), bar diameter (db), concrete compressive strength (fc′), concrete-cover-bar-diameter ratio (c/d), and embedment-length-bar-diameter ratio (l/d). The investigation of the variable number of genetic parameters such as number of chromosomes, head size, and number of genes was undertaken such that 11 different models (M1–M11) were created. The results of accuracy evaluation parameters, namely coefficient of determination (R2), mean absolute error (MAE), and root mean square error (RMSE) imply that the M11 model outperforms other created models for the training and testing stages, with values of (0.925, 0.751, 1.08) and (0.9285, 0.802, 1.11), respectively. The values of R2 and error indices showed that there is very close agreement between the experimental and predicted results. 30 number chromosomes, 9 head size, and 5 genes yielded the optimum model. The parametric analysis revealed that db, c/d, and l/d significantly affected the BS. The FRP rebar diameter size is greater than 10 mm, whereas a l/d ratio of more than 12 showed a considerable decrease in BS. In contrast, the rise in c/d ratio revealed second-degree increasing trend of BS.
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Kluess, Daniel, Carmen Zietz, Tobias Lindner, Wolfram Mittelmeier, Klaus-Peter Schmitz, and Rainer Bader. "Limited range of motion of hip resurfacing arthroplasty due to unfavorable ratio of prosthetic head size and femoral neck diameter." Acta Orthopaedica 79, no. 6 (January 2008): 748–54. http://dx.doi.org/10.1080/17453670810016803.
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Chaoui, R., B. Benoit, M. Entezami, W. Frenzel, K. S. Heling, B. Ladendorf, V. Pietzsch, A. Sarut Lopez, and K. Karl. "Ratio of fetal choroid plexus to head size: simple sonographic marker of open spina bifida at 11–13 weeks' gestation." Ultrasound in Obstetrics & Gynecology 55, no. 1 (December 12, 2019): 81–86. http://dx.doi.org/10.1002/uog.20856.
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Resnik, Anja, Janez Zibert, and Nejc Mekis. "Pelvis imaging: Achieving dose reduction with different patient positions." Nuclear Technology and Radiation Protection 34, no. 4 (2019): 375–83. http://dx.doi.org/10.2298/ntrp190818037r.
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The purpose of this research was to determine how dose area product, effective dose, absorbed doses to specific organs, and image quality changed according to different automatic exposure control positions in pelvis imaging. The research was carried out in two parts. The study was conducted on an anthropomorphic phantom and 200 patients referred to pelvic imaging. We measured the dose area product, field size, height, and mass. Then we calculated the effective dose and absorbed dose for individual organs accordingly. Lateral ionizing cells were first positioned in line with the iliac crests (head towards position) and subsequently, with the femoral neck (head away position). All the images were independently evaluated by three radiologists using ViewDEX and objective image analysis was performed measuring contrast-to-noise ratio and signal-to-noise ratio. We found no significant differences in the Siemens Luminos unit in any of the inspected parameters. However, there was a significant difference in dose area product (37.3 %), effective dose (35.7 %) and average absorbed dose to selected individual organs (36.7 %) when the head away position of the patient was used and the image quality increased. Based on these results, we can propose that the optimal position of the patient regarding the ionizing cells is the head away position.
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Alemaw, Abadi, Dagnew Kalayu, Kibrom Kahsu, and Hadush Redae. "Poverty status and its determinants in rural households of Enda-mohoni woreda, Northern Ethiopia." Ekonomika poljoprivrede 68, no. 3 (2021): 729–44. http://dx.doi.org/10.5937/ekopolj2103729t.
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This research generates specific, contextualized identification of existing poverty status and poverty causing factors in Enda-mohoni woreda in Tigray Region, Ethiopia. Agroecology based cluster sampling technique was employed to select 154 household heads. Logit model was used to analyze household poverty status and FGT poverty index estimation model for poverty incidence analysis. The poverty analysis found a 30.9% headcount ratio, 4.4% poverty gap ratio, and 1% poverty severity. Furthermore, the result of the logistic regression revealed that among the explanatory variables used in the model, family size and agroecological location of the household head were found to positively influence HHs' poverty status at (P<0.01) and (P<0.05) respectively. Whereas, owning livestock and marital status of the HHH were found to negatively influence HHs' poverty status at (P<0.05) and (P<0.1) respectively. It is with appropriate policies that recognize the importance of poverty features and trends would it be possible for more people to make positive exits from poverty risk.
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Yang, Ji Ho, Dong Sun Shin, Jeong-Hun Yoo, Hun Jun Lim, Jun Lee, and Bong Chul Kim. "Anatomical Characteristics of the Masseter Muscle in Mandibular Prognathism." Applied Sciences 11, no. 10 (May 13, 2021): 4444. http://dx.doi.org/10.3390/app11104444.
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Mandibular prognathism causes functional and esthetic problems. Therefore, many studies have been conducted to understand its etiology. Following our previous study, which revealed that the major characteristic of the mandible with prognathism is the volume/length ratio of the mandibular body and condyle, we analyzed the volume and orientation of the masseter muscle, which inserts into the mandibular body, expecting that the difference in the size of the masseter muscle causes the difference in the mandibular size. This study compared the masseter muscle of the participants in the prognathic group to those in the normal group on the volume/length ratio and orientation. The masseter muscle ratios (volume/length); the angle between the superficial and deep head of the masseter muscle; and the three planes (the palatal, occlusal, and mandibular) were analyzed. A total of 30 participants constituted the normal group (male: 15, female: 15) and 30 patients, the prognathic group (male: 15, female: 15). The results showed that the volume/length ratio of the masseter of the normal group was greater than that of the prognathic group (p < 0.05). In addition, the orientation of both the superficial and deep head of the masseter of the participants in the normal group was more vertical with respect to the mandibular plane than that of the prognathic group (p < 0.05). We concluded that the mechanical disadvantage of the masseter muscle of the prognathic group is attributed to mandibular prognathism.
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Mulu, Arega, Preeti Jacob, and G. S. Dwarakish. "Hydraulic Performance of Pervious Concrete Based on Small Size Aggregates." Advances in Materials Science and Engineering 2022 (June 28, 2022): 1–12. http://dx.doi.org/10.1155/2022/2973255.
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The paper aims to study the impact of clogging on pervious concrete mixes and explore a simple method to calculate permeability and clogging using the falling head method in a fabricated unit. The materials used are cementitious materials and aggregates, along with superplasticizers. The cementitious materials used are OPC Grade 53 cement and micro Ground Granulated Blast Furnace Slag (μGGBS). Two separate narrow aggregate gradations are used: 2.36–4.75 mm and 4.75–6.30 mm. The water-binder ratio is taken as 0.25, and the aggregate-binder ratio is taken as 3.33. The compressive strength, permeability, and clogging potential of pervious concrete are calculated. The average permeability for 2.36–4.75 mm and 4.75–6.3 mm is 4.78 mm/s and 8.16 m/s, respectively. The clogging materials used are clay and sand with a concentration of 5 g/l. The introduction of clay slurry reduces the permeability by 69.8% and 74.9%, respectively, and with sand, it decreases by 74.7% and 71.7%, respectively, in its first cycle. The permeability response for such small aggregates is different from the standard coarse aggregates. The paper compares the study’s compressive strength, porosity, and permeability with the existing literature. It concludes that the maximum clogging occurs when the clogging material is introduced to the specimen for the first time. The degradation of permeability depends on the clogging particle’s particulate size and the concrete matrix’s pore size. The smaller aggregates in pervious concrete are not recommended in areas of high siltation.
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Kissi-Abrokwah, Bernard, Soezin Krog, Paul Kobina Annan Bedu-Addo, and Anontise Isaac Aboyom. "EFFECT OF LARGE CLASS SIZE AND TEACHER-LEARNER RATIO ON CLASSROOM MANAGEMENT IN EARLY CHILDHOOD EDUCATIONAL CENTRES IN GHANA." International Journal of Education and Social Science Research 05, no. 05 (2022): 382–401. http://dx.doi.org/10.37500/ijessr.2022.5521.
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The main aim of this study was to investigate how large class size and teacher-to-learner ratio affect classroom management in early childhood educational centres in Ghana. A descriptive survey was used as research design for the study, which was underpinned by positivist philosophical thought. The data was collected using a four-point Likert-type scale questionnaire, to be administered to preschool teachers and head teachers. The sample size for the study was 216 participants and the data was analysed using one-way analysis of variance (ANOVA), mean and standard deviation. It was found that the presence of teacher-to-learner ratio (TLR) in early childhood education centres (ECECs) resulted in poor interaction and communication between preschool teachers and pre-schoolers, which had an effect on teachers’ classroom management. Moreover, in large classes, where teachers are unable to perform effective classroom management, classroom discipline and engagement will be more difficult to achieve than in the smaller classes. Again, the findings revealed that in cases of large class size, preschool teachers were repeating activities and were unable to attend to two events simultaneously in the classroom without having their attention diverted unduly by disruptions. The study also pointed out that positive reinforcement, shaping, giving prompt feedback and giving clear instructions were effective classroom strategies used in managing pre-schoolers in classes of larger size.
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Martínez, M. L., V. Mullin, and A. Schulte-Hostedde. "Variation in sperm morphometry of the African cyprinid Barbus neumayeri (Neumayer’s barb)." Canadian Journal of Zoology 93, no. 4 (April 2015): 259–66. http://dx.doi.org/10.1139/cjz-2014-0196.
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In this study, we explored variation in sperm morphometry of the African cyprinid Barbus neumayeri Fischer, 1884 (Neumayer’s barb) across seven sites with a wide range in dissolved oxygen, from hypoxic swamps to intermittent normoxic streams to well-oxygenated rivers. We explore whether fish physiological condition (K) or hypoxia can affect the reproductive traits, and whether condition–hypoxia dependence of sperm traits including head length (LH), head width (WH), flagellum length (LF), and hydrodynamic ratio (HR) vary across sampling sites. Significant differences were found in fish total length (P = 0.0212), as well as in K, left and right testis masses, total gonad mass, and gonadosomatic index (P < 0.0001 for all traits). Total gonad mass was lower in hypoxic sites than in well-oxygenated sites. Interestingly, the left and right testes from normoxic environments were double the size of testes from hypoxic environments. Despite little variation in sperm flagellum length, sperm heads were longer in swamps than in streams or rivers, giving the sperm head a more hydrodynamic shape. This variation in HR may be beneficial in the more stagnant waters of the swamp compared with the other environments. Future studies are necessary to understand whether variation in sperm morphology correlates with sperm swimming performance and male reproductive capacity.
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SOARES, POLYANA NORONHA, VÂNIA GONÇALVES-ESTEVES, JOÃO SEMIR, and JIMI NAOKI NAKAJIMA. "Chrysolaena glandulosa (Vernonieae, Asteraceae): A new species from Brazil." Phytotaxa 439, no. 3 (April 20, 2020): 295–300. http://dx.doi.org/10.11646/phytotaxa.439.3.11.
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Chrysolaena glandulosa is a new species of Vernonieae (Asteraceae), endemic to the “campos rupestres” of Serra da Canastra National Park and adjacent areas of southwestern Minas Gerais state, Brazil. Chrysolaena glandulosa is characterized by its laxly disposed leaves and lower surface with glandular dots, corolla lobes papillose with glandular dots, and strigose achenes with glandular dots. It is morphologically similar to C. campestris but differs from the latter by presence of glandular dots on the lower surface of the leaves, the ratio between the size of the bracts of the inflorescence and the involucre, and the number of heads and flowers per head. Pollen study confirms that this species belongs to Chrysolaena. A diagnostic key is presented to all Minas Gerais species.
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Cherkerzian, Sara, Ingrid Olson, Raina Fichorova, Salahuddin Ahmed, Rasheda Khanam, Sayedur Rahman, Abdullah Baqui, and Anne CC Lee. "Cord Blood Inflammation and Birth Size in the Bangladesh Projahnmo Pregnancy Cohort." Current Developments in Nutrition 6, Supplement_1 (June 2022): 555. http://dx.doi.org/10.1093/cdn/nzac060.013.
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Abstract Objectives To examine the association between cord blood inflammation and infant birth size in a pregnancy cohort from rural Bangladesh Methods In Sylhet district, Bangladesh, we consecutively enrolled 297 pregnancies and collected prenatal data and umbilical cord dried blood spots at birth (December 2015- 6). Cord blood was analyzed for interleukin (IL)-1α, IL-1β, IL-6, IL-8, and C-reactive protein (CRP). Z score values for weight, length, and head circumference at birth were calculated using the Intergrowth-21 standard. The association between inflammation (>75% vs < = 75%) and birth size was assessed using logistic regression. For birth size outcomes, we assessed small for gestational age (SGA) (<3% and 10% birth weight for GA/sex using Intergrowth-21) as well as birth weight, length, and head circumference z-scores (lowest quartile Z-scores vs others). In model 1, we calculated direct crude associations between exposure (inflammation) and outcome (birth size), and in model 2, adjusted for factors which may be associated both exposure and - independently of exposure - outcome (socioeconomic status, maternal age, maternal nutritional status, infant gestational age and sex). Results Study mothers were a mean (sd) age of 23.7 ± 4.7 years. 34.2% had a maternal upper arm circumference (MUAC) < 22 cm, and 19% exhibited stunting (height < 145 cm). Mean gestational age at birth was 38.9 ± 2.1; 11.5% infants were preterm, 27.3% low birthweight (<2500 g), and 41.3% SGA. Mean birth size z-scores were −1.0 ± 1.1 for weight, 0.1 ± 0.9 for length, and 0.2 ± 1.1 for head circumference. We found no significant associations between cord inflammation biomarkers and SGA status. In model 1, elevated IL-1α and IL-6 exhibited a negative trend with low birth length z scores in crude analysis (odds ratio (OR) = 1.9, 95% CI: 0.9, 3.9). In model 2, statistical trends were observed for IL-1α (OR = 2.2, 95% CI: 1.0, 5.1), IL-6 (OR = 2.1, 95% CI: 0.9, 4.7), and CRP (OR = 2.0, 95% CI: 0.9, 4.6). No associations were observed between cord blood inflammation and birth weight or head circumference z scores. Conclusions Among infants in rural Bangladesh, elevated cord blood inflammation was associated with trends of smaller birth length z-scores. Funding Sources Eunice Kennedy Shriver National Institute of Child Health and Development.