Performance enhancement of an ultrafast all-fiber laser based on an InN saturable absorber using GRIN coupling.

Indium nitride (InN)-based semiconductor saturable absorbers have previously shown advantages for application in near-IR fiber lasers due to their broad modulation depth, ultrafast nonlinear response and thermal stability. However, up to now all demonstrated saturable absorber elements based on InN (either transmissive or reflective) have shown limited performance due to poor coupling and insertion losses. We present here a simple mode-locking device based on a GRIN-rod lens in conjunction with an InN semiconductor saturable absorber mirror (SESAM) for its use in a passively mode-locked all-fiber laser system operating at telecom wavelengths. Our results demonstrate that this coupling element ensures not only a compact, turnkey and alignment-free design but also a highly-stable optical femtosecond pulse train. The reduction of insertion losses (3.5 dB) enables the generation of 90-fs ultrafast pulses with an average power of 40 mW and up to 7 nJ of pulse energy without the need for additional amplification.

Milk yield and composition and body weight of offsprings of mixed-breed goats on semi-arid rangelands with different rainfall.

The objective was to characterize milk yield and composition from mixed-breed goats kidding in winter and grazing rangelands with 221 (n = 15), 334 (n = 20), or 441 (n = 12) mm of annual rainfall in northern Mexico (22-25°N). Weekly milk yield and composition were recorded and progeny growth performance assessed. Body weight loss during lactation was the highest (6.4 kg) for goats on rangeland with 441 mm of rainfall than goats on 221 mm (1.6 kg), or 334 mm (1.8 kg; P < 0.01). The highest daily milk yield was for goats on 221 mm (498 mL; P < 0.01). There was not an evident peak of lactation and milk yield increased uninterruptedly at the end of lactation. Milk fat was negatively related to milk yield and goats on rangeland with 334 mm had the greatest milk fat content (P < 0.001). Milk protein and lactose content were higher in goats on rangeland with 221 mm (P < 0.01). Goat kids on rangelands with 221 and 441 mm grew faster and were heavier (P < 0.001) at weaning than kids reared in other rangelands. Weaning weight was positively related to milk yield (P < 0.001); but not milk components (P > 0.05). In conclusion, moderate milk yield of mixed-breed goats on rangeland is feasible with parturitions in winter, and milk yield is not affected by reduced annual precipitation in rangelands of northern Mexico. Offspring growth performance depends on maternal milk yield, but not milk composition. Nevertheless, slow growth to weaning of offspring had adverse effects on time to reach adequate market weight.

Susceptibilidadaa la hipoxia hipobárica en una estirpe comercial de pollos de engorde / Susceptibiity too hypobaric hypoxia in a commercial strain of broiler chickens

La hipertensión arterial pulmonar (HAP) inducida por la hipoxia hipobárica genera grandes pérdidas económicas en la industria de la carne de pollo. Los pollos Cobb 500 criados bajo condiciones de hipoxia hipobárica (2.638 m de altitud) y temperatura controlada, tuvieron una disminución notable de peso corporal en comparación con los animales criados bajo normoxia relativa (310 m de altitud). Al día 42 de edad la mortalidad acumulada fue de 35,2% en machos y 53,8% en hembras, de la cual, 90,6% en machos y 96,4% en hembras se atribuyó a HAP. Al día 33 de edad, 64% de los pollos desarrollaron HAP (índice cardiaco > 25), 32% presentó ascitis y 82% hidropericardio solamente. Se encontró mayor mortalidad entre la tercera y quinta semanas. Se concluye que la ascitis puede o no estar presente en animales enfermos y que el hidropericardio por sí solo se asocia con la presencia de HAP. El tiempo de exposición a hipoxia hipobárica no influye en la forma de presentación, ni afecta la manifestación de la HAP, mientras que la susceptibilidad a la muerte por HAP se debe a un factor individual de adaptación. Por tanto, es factible que el grado de susceptibilidad individual determine los límites entre la compensación de la hipoxia, el desarrollo de la HAP (cuadro agudo o crónico) y la muerte de los animales. El 36% de los pollos expuestos a hipoxia hipobárica tuvieron un buen desempeño productivo; estos pollos resistentes deberían ser objeto de programas de selección genética.

The pulmonary arterial hypertension syndrome (PAH) in broilers due to hypobaric hypoxia generates big economic losses. We studied the effect of exposure to hypobaric hypoxia (2,638 m above sea level) in PAH development in Cobb 500 broilers maintained under controlled temperature conditions. These broilers had lower corporal weight than those raised under relative normoxic conditions (310 m above sea level). At 42 days of age the accumulative mortality was 35.2% in males and 53.8% in females; of these values, 90.6% in males and 96.4% in females were due to PAH. At 33 days of age, 64% of broilers developed PAH (mass cardiac index values > 25), 32% had developed ascites, and 82% only hydropericardium. Higher mortality was encountered between the weeks three and five of age. Ascites may or may be not present in affected chickens and hydropericardium alone is related to PAH. PAH may occur at any age, and cardiac index values are not time dependent. Susceptibility to develop PAH is an individual factor related to poor genetic adaptation. Therefore, individual susceptibility determines the possibilities to compensate the effects of hypoxia, the PAH characteristics, as related to its duration. The 36% of chickens exposed to hypobaric hypoxia had a good productive performance; these resistant animals should be the target in programs for genetic selection.

[Occlusion of patent ductus arteriosus with a Gianturco-Grifka device. First case at the Instituo Mexicano del Seguro Social (IMSS)]. / Oclusión de conducto arterioso permeable con dispositivo de Gianturco-Grifka. Primer caso en el IMSS.

We present the initial experience of closing of patent ductus arteriosus (PDA) with a new device; Gianturco-Grifka, at the General Hospital of The Medical Center "La Raza". The patient was a 4 year's old girl, in whom we detected continuous murmur in the second intercostal space, echocardiography showed a long conical patent ductus arteriosus 4.9 mm of diameter, systolic pressure of the pulmonary artery was 35 mm Hg with QP/QS 1.6:1. Hemodynamic study revealed a long conical ductus arteriosus 5 mm of diameter, type A1 from Krichenko classification. We proceeded to occlude the PDA with a Gianturco-Grifka device of 7 mm. Immediately after the PDA occlusion the shunt disappeared, there were no complications during the procedure. More cases are needed to determine long term benefits and limitations, of this procedure. However we conclude that technically it is easy to use. There is greater decrease of residual shunt that the one reported with other devices.

[A comparative study of Rashkind, Grifka and coil devices in percutaneous closing of patent ductus arteriosus]. / Estudio comparativo entre dispositivos de Rashkind, Grifka y Coil para el cierre percutáneo del conducto arterioso.

This study was performed to evaluate the efficacy of transcatheter Coil and Grifka closure of the patent ductus arteriosus in comparison to our experience with the Rashkind umbrella device. Ninety seven patients (36 male and 61 females) underwent occlusion of the PDA. The following variables were compared: age, sex, ductus diameter, morphology, device, occlusion time, residual shunt, multiple device and complications. Data obtained were compared using the Student's test and Chi 2. Median patient age was 7.82 +/- 6.89, forty five patients underwent transcatheter Rashkind-17 closure, 19 patients with Rashkind-12, 18 patients with Coil and 13 patients with Grifka device, in two patients the closure could not be performed. There were differences between the morphology and device used (p = 0.008), between the ductus diameter and device used (p < 0.001). There was immediate closure in 26.7% in the Rashkind-17 group compared with, 57.9% for the Rashkind-12 group, 83.3% for Coil group and of 91.7% for Grifka group. The occlusion within 24 hrs of implantation was 60% with Rashkind-17, 78.9% with Rashkind-12, 94.4% with Coil and 100% with Grifka. Residual shunt persisted for more than a year in 7 patients with Rashkind-17 and 1 with Rashkind 12, (p = 0.001), in 4 patients two devices wore placed. The complications were, 15.5% for Rashkind-17, 26.3% for Rashkind-12, 5.2% for Coil and 30% for Grifka, (p = 0.004), one coil and one Grifka embolized. Transcatheter Coil and Grifka occlusion are more effective in achieving immediate closure than the Rashkind device. The indication to use each device is made according to the morphology and size of the ductus.

[Percutaneous occlusion of patent ductus arteriosus with Rashkind device. 4-year follow-up]. / Oclusión percutánea de conducto arterioso permeable con dispositivo de Rashkind. Seguimiento a 4 años.

We present the results and follow up of ductus arteriosus closure with the Rashkind device. Sixty-six devices were implanted in 63 patients, 41 women and 22 men, with a mean age of 8.2 years. We determined the diameter of the duct, the presence or absence of immediate residual leak at 3 months, 6 months, 1 year, and every year of follow-up by ecocardiography. The hemodynamic determinations showed: type A morphology in 49, type C in 7 and type E in 7; with a mean diameter of 4.2 +/- 1.4 mm (range of 2.3 to 8.7 mm) and a Qp/Qs 2.2 +/- 1.5 (range 0.7 to 8.6). Forty-five 17 mm devices and 18 of 12 mm were used. The incidence of immediate residual leak was 65% (n-41); at 24 hrs. Post-procedure was 31.7% (n-20) and at one year 7.9% (n-5). Three patients with persistent leak had implantation of a second Rashkind device and one more patient an endovascular coil, the other patient is waiting for a second occlusor. Minor complications occurred in 15.8% (n-10). Results show an occlusion rate at 24 hrs of 68% and at one year of 92%; no patient presented migration of the device, hemolysis or obstruction of the pulmonary artery branches. We consider that occlusion of the ductus arteriosus with the Rashkind device is a safe and effective option for the treatment of this pathology.

[Pulmonary valvuloplasty. Long term results at the Centro Medico la Raza]. / Valvuloplastía pulmonar: resultados a largo plazo. Experiencia en el Centro Médico La raza.

The purpose of this study was to evaluate the immediate and long term results of pulmonary valve ballon dilation, and to determine the prognostic factors of failure in 109 patients (60 female and 49 male), aged 7.04 +/- 8.4 years. Seventy two patients (66.1%) had isolated valvular stenosis and 33.9% presented associated lesions. Peak systolic pressure gradient across the pulmonary valve decreased from 89.53 +/- 37.23 to 20.8 +/- 19.41 mmHg (p < 0.0001) after valvuloplasty. Forty three patients developed reactive infundibular stenosis after valvuloplasty with a systolic gradient of 19.65 +/- 35.64 mmHg. At a mean period of 8 years of follow-up the pressure gradient was 20.75 +/- 14.32 (p < 0.001). Valvuloplasty was successful in 86.2% of the cases with a global mortality of 1.9%, minor complications in 15.2%, and a failure rate of 13.8%. At follow-up restenosis developed in 6.7%. The comparative analysis between the groups of success and failure yield as significant risk factors for failure an age younger than 3.5 years and a pulmonary valve with displastic (p < 0.05) or combined morphology (p < 0.05). This group had also more complications and higher systolic gradients and right ventricular pressures post-dilation (p < 0.05). Pulmonary valvuloplasty is a safe and effective procedure for the treatment of pulmonary valve stenosis with a good immediate and long-term results, and is now considered the treatment of choice.

[Percutaneous transluminal angioplasty in aortic coarctation. The short- and median-term results]. / Angioplastía transluminal percutánea en coartación aórtica. Resultados a corto y mediano plazo.

Percutaneous transluminal angioplasty (PTA) was performed in 34 patients with aortic coarctation (Ao Co). One of them with coarctation after surgical correction, the rest were native Ao Co. We used one balloon in 28 patients and two balloons simultaneously in 6. They were separated in three groups according to the degree of aortic arc hypoplasia. Group I (mild to moderate hypoplasia N = 9) the gradient dropped 39% with angiographic improvement of 48% during the follow-up (m = 13.1 months). Three cases with restenosis, 2 were satisfactory dilated and one was sent to surgery. In Group II (severe hypoplasia N = 4) the gradient dropped 31% with angiographic improvement of 30% (follow-up 16.3 months). Two cases with recoarctation were sent to surgery. In Group III (without hypoplasia N = 21) we obtained dropped of gradient of 71% with angiographic improvement of 60% (follow-up 18.5 months). Two cases were redilated successfully. The complications were: cerebral hemorrhage with death due to hypertensive crisis, (1) cerebral embolism, (1) thrombosis in the puncture site 1 and small aneurysm in dilated zone. (1) We think PTA is a good choice to conventional surgery with low rate of morbidity-mortality. The results depend basically on the anatomic type of coarctation and degree of aortic arch hypoplasia.

[Valvuloplasty with balloon catheter in biologic prosthesis. Reality or illusion]. / Valvuloplastía con cáteter de globo en prótesis biológicas. Realidad o ilusión.

We performed catheter balloon valvuloplasty (CBV) on 8 stenotic operatively-excised bioprosthetic valves (2 Hancock and 6 Ionescu Shiley). Pathology of valves before CBV included degenerative changes: commissural fusion by mounds of calcific deposits (2 valves), fibrotic and focally calcified leaflets (7 valves) and stiff and thick valves (1 valve). Inflation of the balloon resulted in commissural splitting (2 valves), leaflet cracks and fractures (3 valves). Removal of the deflated balloon catheter was associated with debris dislodgement (3 valves). In one case the valve was unable to close with potential for acute regurgitation. Thus, CBV of bioprosthetic valves can split fused commissures by similar mechanisms as in native valves. CBV may fracture calcific deposits causing acute emboli. It can also disrupt the leaflets causing acute insufficiency. The findings suggest a limited role of CBV in the treatment of stenotic bioprosthetic valves in mitral and aortic position.