Modelling migration in birds: competition's role in maintaining individual variation.

Animals exhibit extensive intraspecific variation in behaviour. Causes of such variation are less well understood. Here, we ask when competition leads to the maintenance of multiple behavioural strategies. We model variability using the timing of bird migration as an example. Birds often vary in when they return from non-breeding grounds to establish breeding territories. We assume that early-arriving birds (counting permanent residents as 'earliest') select the best territories. But arriving before the optimal (frequency-independent) breeding date incurs a fitness penalty. Using simulations, we find stable sets of return dates. When year-round residency is viable, the greatest between-individual variation occurs when a small proportion of permanent residents is favoured, and the rest of the population varies in their return times. However, when fitness losses due to year-round residency exceed the benefits of breeding in the worst territory, all individuals migrate, although their return dates often vary continuously. In that case, individual variation is inversely related to fitness risks and positively related to territory inequality. This result is applicable across many systems: when there is more to gain through competition, or when its risks are small, a diversity of individual strategies prevails. Additionally, stability can depend upon the distribution of resources.

Recurrence rate of intramucosal gastric cancer with positive vertical margin due to lesion damage during endoscopic submucosal dissection.

BACKGROUND AND STUDY AIM: In principle, additional surgery is performed after endoscopic submucosal dissection for early gastric cancer if the vertical margin is positive, regardless of lesion damage. The recurrence rate of vertical margin-positive lesions due to lesion damage after endoscopic submucosal dissection is unknown, and unnecessary surgeries may be performed. In this study, we investigated whether there was a difference in the recurrence rate between vertical margin-positive lesions due to lesion damage and vertical margin-negative lesions. PATIENTS AND METHODS: We included 1,294 intramucosal gastric cancer lesions that were resected by endoscopic submucosal dissection between January 2008 and December 2016, without additional surgery. The lesions were divided into the Damage and No damage groups based on vertical margin status. The Damage group had only one non-curative indication: a positive vertical margin due to lesion damage. The No damage group had no non curative indications. We compared the recurrence rate between the Damage and No damage groups. RESULTS: The recurrence rates of the Damage and No damage groups were 0% (0/23; 95% confidence interval: 0-14.8%) and 0% (0/1,271; 95% confidence interval: 0-0.003%), respectively, with no statistically significant difference. CONCLUSIONS: In intramucosal gastric cancer, the recurrence rate of vertical margin-positive lesions due to lesion damage was 0%, which did not differ from that of vertical margin-negative lesions with curative resection. Follow-up, instead of additional surgery, may be an option for patients with non-curative resection when the only non-curative indication is a positive vertical margin due to lesion damage.

Effectiveness of modified oral steroid administration for preventing esophageal stricture after entire circumferential endoscopic submucosal dissection.

Esophageal stricture occurs at a high rate after endoscopic submucosal dissection, especially after entire circumferential dissection, leading to poor quality of life. This retrospective cohort study evaluated the stricture rate in circumferential mucosal defect cases following modified steroid administration. We enrolled 22 consecutive patients who underwent entire circumferential endoscopic submucosal dissection for superficial esophageal cancer between April 2010 and April 2015 at our hospital. Until January 2013, a systemic steroid-prednisolone-was administered at 30 mg/day and tapered over 8 weeks in the original method group (original group). From February 2013, 30 mg of prednisolone was administered orally for 3 weeks and then the dose was reduced in 5 mg decrements every 3 weeks. This group was classified as the modified method group (modified group). We retrospectively compared the stricture rates between the two groups. The postoperative stricture rate was significantly lower in the modified group (36.4%; 4/11 patients) than in the original group (82%; 9/11 patients; P = 0.04). The mean number of endoscopic balloon dilatation procedures was significantly lower in the modified group (6.2 ± 11.3) than in the original group (19.4 ± 15.3; P = 0.023). Pneumonia and oral herpes infection, which are adverse events potentially associated with steroid administration, were observed in the original group. Candida esophagitis, arthritis, and steroid-related myopathy were observed in the modified group. This modified systemic steroid administration was effective for patients with entire circumferential mucosal defect. The safety of this method was also demonstrated.

Polyglycolic acid sheet and fibrin glue for preventing esophageal stricture after endoscopic submucosal dissection: a historical control study.

There have been several reports that steroid administration is effective at preventing strictures after endoscopic submucosal dissection (ESD). However, adverse events after steroid use are of great concern. We have reported that shielding with a polyglycolic acid (PGA) sheet and fibrin glue can be useful for prevention of stricture after ESD. We conducted a retrospective analysis of efficiency of shielding with a PGA sheet and fibrin glue for prevention of esophageal stricture compared with intralesional steroid injection. ESD was performed on a total of 489 lesions in 400 patients for superficial esophageal cancer from January 2012 to July 2016. Of these, 39 lesions were enrolled in the study group (PGA sheet and fibrin glue) and 31 lesions were enrolled in the control group. The incidence of postoperative stricture at 6 weeks and the number of sessions of endoscopic balloon dilatation (EBD) required to resolve any strictures were evaluated. The post-ESD stricture rate was 9.1% in the study group (3/33 patients), which was not significantly lower than the stricture rate of 10.3% in the historical control group (3/29 patients; p = 1.00). The mean number of EBD was 0.057 ± 0.24 in the study group and 1.9 ± 5.1 in the control group, which was not significant (P = 0.95). PGA sheet and fibrin glue appear to be a promising option for the prevention of esophageal stricture similar to the effect of intralesional steroid injection.

Vascular density of superficial esophageal squamous cell carcinoma determined by direct observation of resected specimen using narrow band imaging with magnifying endoscopy.

Observation of the microvasculature using narrow band imaging (NBI) with magnifying endoscopy is useful for diagnosing superficial squamous cell carcinoma. Increased vascular density is indicative of cancer, but not many studies have reported differences between cancerous and noncancerous areas based on an objective comparison. We observed specimens of endoscopic submucosal dissection (ESD) using NBI magnification, and determined the vascular density of cancerous and noncancerous areas. A total of 25 lesions of esophageal squamous cell carcinoma that were dissected en bloc by ESD between July 2013 and December 2013 were subjected to NBI magnification. We constructed a device that holds an endoscope and precisely controls the movement along the vertical axis in order to observe submerged specimens by NBI magnification. NBI image files of both cancerous (pathologically determined invasion depth, m1/2) and surrounding noncancerous areas were created and subjected to vascular density assessment by two endoscopists who were blinded to clinical information. The invasion depth was m1/2 in 20, m3/sm1 in four and sm2 in one esophageal cancer lesion. Mean vascular density was significantly increased in cancerous areas (37.6 ± 16.3 vessels/mm2) compared with noncancerous areas (17.6 ± 10.0 vessels/mm2) (P < 0.05). The correlation coefficients between vascular density determined by two endoscopists were 0.86 and 0.81 in cancerous and noncancerous areas, respectively. Receiver operating curve (ROC) analysis revealed that the area under the curve (AUC) of vascular density was 0.895 (95% CI, 0.804-0.986). For this ROC curve, sensitivity was 78.3% and specificity was 87.0% when the cutoff value of vascular density was 26 vessels/mm2. NBI magnification confirmed significant increases in vascular density in cancerous areas compared with noncancerous areas in esophageal squamous cell carcinoma. The rates of agreement between vascular density values determined by two independent operators were high.

Generation of spin currents by surface plasmon resonance.

Surface plasmons, free-electron collective oscillations in metallic nanostructures, provide abundant routes to manipulate light-electron interactions that can localize light energy and alter electromagnetic field distributions at subwavelength scales. The research field of plasmonics thus integrates nano-photonics with electronics. In contrast, electronics is also entering a new era of spintronics, where spin currents play a central role in driving devices. However, plasmonics and spin-current physics have so far been developed independently. Here we report the generation of spin currents by surface plasmon resonance. Using Au nanoparticles embedded in Pt/BiY(2)Fe(5)O(12) bilayer films, we show that, when the Au nanoparticles fulfill the surface-plasmon-resonance conditions, spin currents are generated across the Pt/BiY(2)Fe(5)O(12) interface. This spin-current generation cannot be explained by conventional heating effects, requiring us to introduce nonequilibrium magnons excited by surface-plasmon-induced evanescent electromagnetic fields in BiY(2)Fe(5)O(12). This plasmonic spin pumping integrates surface plasmons with spin-current physics, opening the door to plasmonic spintronics.

Spin Hall magnetoresistance induced by a nonequilibrium proximity effect.

We report anisotropic magnetoresistance in Pt|Y(3)Fe(5)O(12) bilayers. In spite of Y(3)Fe(5)O(12) being a very good electrical insulator, the resistance of the Pt layer reflects its magnetization direction. The effect persists even when a Cu layer is inserted between Pt and Y(3)Fe(5)O(12), excluding the contribution of induced equilibrium magnetization at the interface. Instead, we show that the effect originates from concerted actions of the direct and inverse spin Hall effects and therefore call it "spin Hall magnetoresistance."

Clinical advantage of endoscopic submucosal dissection over endoscopic mucosal resection for early mesopharyngeal and hypopharyngeal cancers.

BACKGROUND AND STUDY AIMS: In previous series, endoscopic mucosal resection (EMR) has been used for the treatment of early-stage mesopharyngeal and hypopharyngeal cancers to preserve patients' quality of life. Endoscopic submucosal dissection (ESD) offers potential advantages in comparison to EMR. So the aim of this retrospective study was to assess the utility of ESD compared with EMR for early-stage cancers of the meso- and hypopharynx. PATIENTS AND METHODS: We studied 56 patients with 69 lesions who underwent either EMR or ESD between April 2001 and December 2008. EMR was performed until January 2007, and ESD was performed from February 2007 onward. We evaluated the en bloc resection rate, R0 resection rate, and treatment-related complications as short-term outcomes. Local recurrence, lymph node metastasis, and disease-related deaths were compared to evaluate long-term outcomes. RESULTS: The en bloc and R0 resection rates were respectively 98 % and 79 % in the ESD group and 37 % and 26 % in the EMR group. There were no cases of treatment-related complications in the EMR group, but postoperative subcutaneous emphysema was observed in two patients in the ESD group. In the EMR group, one patient developed a local recurrence and one developed metastasis to the cervical lymph node and died of primary cancer. CONCLUSIONS: ESD is a useful method of treatment for early mesopharyngeal and hypopharyngeal cancers and may be superior to EMR.

Endoscopic submucosal dissection for treatment of mesopharyngeal and hypopharyngeal carcinomas.

BACKGROUND AND STUDY AIMS: Application of the endoscopic submucosal dissection (ESD) technique, as well as elevation of the larynx in cooperation with an otolaryngologist, under general anesthesia has enabled en-block resection of early mesopharyngeal and hypopharyngeal carcinomas. The aim of this study was to retrospectively evaluate the safety of ESD and the efficacy of the elevation of the larynx for treatment of early mesopharyngeal and hypopharyngeal carcinomas. PATIENTS AND METHODS: The study included 16 lesions in 13 patients who underwent ESD. To provide a sufficient working space, the larynx was elevated under direct laryngoscopy, and a tube was inserted and fixed onto the laryngeal side using the slot on the back of the laryngoscope. RESULTS: The median maximum diameter of the lesions was 12.5 mm (range 2 - 37 mm). The en-block resection rate was 93.8 %. Lateral surgical margins in two patients were difficult to evaluate for technical reasons. The tube could not be removed from four patients on the day of the procedure due to laryngeal edema caused by the local injection. No serious complications were observed. Oral food intake was possible after a mean of 3.3 postoperative days. CONCLUSIONS: With adequate intraoperative and postoperative management, ESD with elevation of the larynx may be very efficient and safe for endoscopic treatment of pharyngeal lesions.

Connection between charge fluctuations and the coherent temperature in the heavy-fermion system SmOs4Sb12: a {121, 123}Sb NQR study.

We report {121, 123}Sb nuclear quadrupole resonance measurements under pressure in a novel heavy fermion (HF) system SmOs4Sb12. The nuclear spin-spin relaxation rate 1/T{2} exhibits a distinct peak near the coherent temperature of the Kondo effect. The isotope effect of 121Sb and 123Sb indicates that the peak in 1/T{2} is electrical in origin. The connection between the peak in 1/T{2} and the development of coherency of the Kondo effect is robust even under pressure. It is conjectured that charge fluctuation plays an important role in forming the HF state in SmOs4Sb12.

Coexistence of strongly mixed-valence and heavy-fermion character in SmOs4Sb12 studied by soft- and hard-X-ray spectroscopy.

Sm-based heavy-fermion compound SmOs4Sb12 has been investigated by soft x-ray (hnu=1070-1600 eV) and hard x-ray (HX; hnu=7932 eV) spectroscopy. The HX photoemission spectroscopy clearly demonstrates that the strongly mixed-valence state and the heavy-fermion state coexist in the bulk. It is found that the Sm valence decreases below 100 K, indicating that the Kondo coherence develops with approaching the proposed Kondo temperature. Our theoretical analyses suggest that the origin of the coexistence in SmOs4Sb12 is the coincidence of two conditions, namely, (i) the energy difference between Sm divalent and trivalent states is very small and (ii) the hybridization between Sm 4f and conduction electrons is weak.

Drastic change in transport of entropy with quadrupolar ordering in.

The antiferroquadrupolar ordering of is explored by probing thermal and thermoelectric transport. The lattice thermal conductivity drastically increases with the ordering, as a consequence of a large drop in carrier concentration and a strong electron-phonon coupling. The low level of carrier density in the ordered state is confirmed by the anomalously large values of the Seebeck and Nernst coefficients. The results are reminiscent of and suggest that both belong to the same class of partial metal-insulator transitions. The magnitude of the Nernst coefficient, larger than in any other metal, indicates a new route for Ettingshausen cooling at Kelvin temperatures.

Purification and some properties of ß-mannanase from Bacillus sp.

ß-Mannanase produced by Bacillus sp. W-2, isolated from decayed commercial konjak cake, was purified from the culture supernatant by (NH4)2 SO4 precipitation, adsorption to konjak gel, and column chromatography with DEAE-cellulose, Sephadex G-100 and Sephacryl S-200. Its molecular size was estimated by SDS-PAGE as 40 kDa, and by gel filtration as 36 kDa. The enzyme was most active at pH 7 and 70°C and was stable for at least 1 h between pH 5 and 10 and below 60°C. Its activity was completely inhibited by Hg(2+). The enzyme hydrolysed galactomannan better than glucomannan and mainly produced mannose and mannobiose.

Relation of serum lipoprotein lipids and apolipoproteins to obesity in children: the Bogalusa Heart Study.

BACKGROUND: The relationship of serum lipoprotein lipids and apolipoproteins to obesity was studied in a biracial sample of 2,816 children of ages 5-17 in Bogalusa, Louisiana. METHODS: Two measures of obesity were used: fatness (subscapular skinfold thickness) and fat centrality (the ratio of subscapular to triceps skinfold thickness). Plasma insulin and glucose were included as metabolic markers related to obesity. RESULTS: The obesity associations were relatively strong with insulin (rs = 0.29, P less than 0.001, skinfold; rs = 0.15, P less than 0.001, skinfold ratio) and triglycerides (rs = 0.25, P less than 0.001, skinfold; rs = 0.19, P less than 0.001, skinfold ratio). The relationships of serum low-density lipoprotein cholesterol (LDL-C) (rs = 0.17, P less than 0.001, skinfold; rs = 0.13, P less than 0.001, skinfold ratio) and apolipoprotein (apo) B (rs = 0.16, P less than 0.001, skinfold; rs = 0.13, P less than 0.001, skinfold ratio) with the obesity measures were of lesser magnitude, but persisted after adjustment for insulin and triglycerides. The inverse association of obesity to serum high-density lipoprotein cholesterol (HDL-C) (rs = -0.13, P less than 0.001, both skinfold and skinfold ratio) and apo A-I (rs = -0.04, P = 0.03, skinfold; rs = -0.05, P = 0.004, skinfold ratio) was significant only before adjustment for insulin and serum triglycerides. Multiple linear regression of obesity measures showed that, like insulin, serum triglycerides had consistently higher standardized coefficients than LDL-C, HDL-C, apo B, and apo A-I. Apo A-I and apo B added only a small amount (less than 2%) of information to the relationship of serum lipoproteins with obesity measures. CONCLUSION: These results indicate that serum very-low-density lipoprotein (VLDL) levels are directly and independently related to obesity. The well-known inverse association between obesity and serum HDL-C is not independent, but secondary to the elevated VLDL or triglyceride levels associated with obesity. While associations of obesity and lipoprotein cholesterol are found, far fewer occur with apolipoproteins, especially Apo A-I. Interesting race and sex differences in the relationship of obesity to serum lipoproteins and apoproteins are noted, being greater among white children and more consistent in white males.

Measurement of apolipoprotein B as a screening test for identifying children with elevated levels of low-density lipoprotein cholesterol.

We compared the efficacy of two screening tests, measurement of apolipoprotein B (apo B) levels and measurement of serum total cholesterol levels, in detecting elevated low-density lipoprotein cholesterol (LDL-C) values in children. We studied 2850 children, aged 5 to 17 years, who had fasting lipid, lipoprotein, and apolipoprotein levels measured as part of the Bogalusa Heart Study. The test characteristics of apo B were superior to those of serum total cholesterol in screening children to detect elevated levels of LDL-C (greater than or equal to 95th percentile) and moderately elevated LDL-C levels (greater than or equal to 80th percentile). Unusually high or low values of high-density lipoprotein cholesterol are responsible for most of the misclassification that occurs when measurement of total cholesterol is used as a screening test for identifying children with elevated levels of LDL-C. This confounding effect of high-density lipoprotein cholesterol was eliminated when measurement of apo B levels was used as a screening test. Because the apo B test is more specific at a given sensitivity than the total cholesterol test, the apo B test can cost more and still be less expensive as a screening strategy. As the methods for determining apolipoprotein levels become standardized and readily available, the measurement of apolipoproteins could be developed into superior screening tests for the identification of patients with dyslipidemias.

Serum total cholesterol screening for the detection of elevated low-density lipoprotein in children and adolescents: the Bogalusa Heart Study.

The use of serum total cholesterol measurement was evaluated as a screening tool to predict elevated levels of low-density lipoprotein cholesterol in 2857 children and adolescents, aged 5 to 17 years, examined in 1981 and 1982. Subjects were from the biracial community of Bogalusa, Louisiana. For selected serum total cholesterol values (150 to 210 mg/dL, 3.88 to 5.43 mmol/L), sensitivities were higher for blacks than whites and higher for females than males, whereas the positive predictive values were higher for whites than blacks and higher for males than females. With the age-, race-, and sex-specific 95th percentiles of serum total cholesterol levels as cutoff points, only 44% to 50% of subjects with elevated low-density lipoprotein cholesterol levels (greater than or equal to 95th percentile) were detected, and approximately 50% of those identified had false-positive results. Lowering the serum total cholesterol cutoff point increased the sensitivity, but decreased the specificity and positive predictive value. At the 75th percentiles of serum total cholesterol levels, sensitivities were 92% to 95% for females and 100% for males and specificities were 78% to 79%, but the false-positive results increased to 81% to 84%. The low cost and ease of obtaining serum total cholesterol measurements contribute to its appeal as a screening tool for hyperlipidemia. However, its poor test characteristics make serum total cholesterol measurement inefficient as a screening tool for detecting elevated levels of low-density lipoprotein cholesterol in children and adolescents.

Parental history of cardiovascular disease as an indication for screening for lipoprotein abnormalities in children.

We studied the relationship between parental history of cardiovascular disease and risk for adverse lipid and lipoprotein levels in a total community study of 3313 children (ages 4 to 17 years, 63% white, 37% black). Older white children (11 to 17 years) with a parental history of heart attack or diabetes were 4.3 and 5.6 times, respectively, more likely to have high levels (greater than or equal to 95th percentile) of serum total cholesterol than those without such a history (all p less than 0.05). White children with a parental history of heart attack or diabetes were twice as likely to have an elevated (greater than or equal to 95th percentile) low-density lipoprotein cholesterol (LDL-C) level than those without such a history (both p less than 0.05). In contrast, parental history of cardiovascular disease did not predict elevated levels of total cholesterol or LDL-C in black children. However, older black children with a parental history of heart attack, hypertension, or diabetes were 4 1/2 to 5 times more likely to have low levels (less than or equal to 5th percentile) of high-density lipoprotein cholesterol than those without such a history (all p less than 0.05). Only 40% of white children and 21% of black children with elevated LDL-C levels had a parental history of vascular disease. These findings raise questions about the current practice of screening only children with a family history of cardiovascular disease to identify those with elevated total cholesterol and LDL-C levels.

Echocardiographic functions and blood pressure levels in children and young adults from a biracial population: the Bogalusa Heart Study.

M-mode echocardiograms were obtained on 651 healthy subjects, 7-22 years of age, whose diastolic blood pressure levels remained in the same height-, race-, and sex-specific decile during two biannual examinations. Echocardiographic measures of heart size and dynamics were compared across the total blood pressure distribution. Left ventricular stroke volume, cardiac output and ejection fraction, minor axis shortening, velocity of circumferential fiber shortening, and peripheral vascular resistance were correlated with blood pressure levels. There were positive correlations (p less than .001) of cardiac output and stroke volume with both systolic and diastolic blood pressure levels. Left ventricular output and stroke volume were associated with measures of body size, especially height, weight, ponderal index, and body surface area (p less than .001). The left ventricular output and stroke volume increased with age and with systolic blood pressure quintiles in the four race-sex groups. With adjustment for systolic blood pressure and measures of body size, white males had greater cardiac output (1.25 l/minute for ages 18-22 years, p = .01) and stroke volume than black males. Black males had higher peripheral resistance (4.5 mm Hg/(l/minute), p = .01) than whites. These results suggest that different hemodynamic mechanisms operate in the early phase of hypertension in blacks vs. whites in this population.