8-beam local oscillator array at 4.7 THz generated by a phase grating and a quantum cascade laser.

We present an 8-beam local oscillator (LO) for the astronomically significant [OI] line at 4.7 THz. The beams are generated using a quantum cascade laser (QCL) in combination with a Fourier phase grating. The grating is fully characterized using a third order distributed feedback (DFB) QCL with a single mode emission at 4.7 THz as the input. The measured diffraction efficiency of 74.3% is in an excellent agreement with the calculated result of 75.4% using a 3D simulation. We show that the power distribution among the diffracted beams is uniform enough for pumping an array receiver. To validate the grating bandwidth, we apply a far-infrared (FIR) gas laser emission at 5.3 THz as the input and find a very similar performance in terms of efficiency, power distribution, and spatial configuration of the diffracted beams. Both results represent the highest operating frequencies of THz phase gratings reported in the literature. By injecting one of the eight diffracted 4.7 THz beams into a superconducting hot electron bolometer (HEB) mixer, we find that the coupled power, taking the optical loss into account, is in consistency with the QCL power value.

Efficiency of multi-beam Fourier phase gratings at 1.4 THz.

We compare the results of simulated and measured power efficiency and far-field beam pattern, for two reflective Fourier phase gratings, designed to generate 2 × 2 and 2 × 4 beams respectively from a single-beam, coherent source at 1.4 THz. The designed surface structures were manufactured on aluminum plates by a computer numerical control (CNC) micro-milling machine. Despite small differences between the designed and fabricated gratings, we measured power efficiencies of both gratings to be around 70%, which is in a good agreement with the simulated values. We also find a good agreement between the simulated and measured diffracted beam size and spatial distribution. We demonstrate the application of both gratings as multiple beam local oscillators to simultaneously pump (or operate) a 4-pixel array of superconducting heterodyne mixers.

Decreased Expression of Bioinformatically Predicted piwil2-targetting microRNAs, miR-1267 and miR-2276 in Breast Cancer.

PURPOSE: Human Piwil2, a member of Piwi subfamily of Argonaute proteins, is primarily expressed in testis, where it regulates self-renewal of germ cells. However, its ectopic expression has been reported with several tumors, including breast cancer. The upregulation of piwil2 in various stages of breast cancer suggested its suitability as a novel tumor biomarker. Considering the vital role of microRNAs (miRNAs) in regulating the expression of most human genes, we hypothesized a concomitant downregulation of the bioinformatically-predicted piwil2-targetting microRNAs in breast cancer.  METHOD: We employed different bioinformatic tools to predict piwil2-targeting miRNAs. Then, from the list of predicted miRNAs, we chose two less studied miRNAs (miR-1267 and miR-2276) for experimental validation. Using a real-time RT-PCR approach, we quantified the relative expression of the miRNAs in 31 pairs of formalin-fixed paraffin-embedded tumor/non-tumor tissue samples. RESULTS: Our data revealed a noticeable but not statistically significant (P = 0.133) downregulation of miR-1267 in tumor samples, compared to non-tumor samples obtained from the same patients. Downregulation of miR-1267 was more significant in higher grades of malignancies (fold change = 2.39, P = 0.033) and also in lymph nodes containing high-grade tumor cells (fold change = 6.66, P = 0.02).  Interestingly, a significant upregulation of miR-1267 was observed in tumors at high stages (stage 3a, 3b), compared to low stages (stage 2a, 2b) (fold change = 8.05, P = 0.048). Similar patterns of expression alteration were also observed for miR-2276. CONCLUSION: Altogether, our findings suggest a probable tumor suppressor role for miR-1267 and miR-2276 in breast tumor initiation and progression, but a probable promoting role for them in invasion and metastasis.

Relación entre potencia aeròbica y anaeròbica y el Special Judo Fitness Test (SJFT) en judocas masculinos iraníes de élite / Relationship between aerobic and anaerobic power, and Special Judo Fitness Test (SJFT) in elite Iranian male judokas

Introducción: El objetivo de estudio fue la evaluación de la relación entre las potencias aeróbica y anaeróbica, así como la prueba especial de aptitud física para el judo en los judokas masculinos de élite. Método: Diecinueve judokas de élite-edad 24,3 (3,1) años, altura 1,78 (0l,06) m, masa corporal 76,4 (11,2) kg, índice de masa corporal 20,2 (3,6) kg•m2 y grasa corpora 11,0 (1,8)-realizaron una prueba de esfuerzo en cinta, la prueba anaeróbica de Wingate para brazos, y la prueba especial de aptitud física para el judo. La prueba de esfuerzo en cinta calculó la captación máxima de oxígeno (VO2max) y la prueba anaeróbica de Wingate evaluó la potencia máxima y media, que describen el rendimiento a corto plazo y la resistencia muscular local, respectivamente. Resultados: El índice de la prueba especial de aptitud física para el judo guardó una relación directa inversa al índice VO2max (r = -0,87, p < 0,01), potencia máxima (r = -0,74, p < 0,01) y potencia media (r = -0,62, p < 0,05). Discusión: Basándonos en estos hallazgos se ha demostrado que la prueba especial de aptitud física para el judo es una prueba de campo que describe principalmente la potencia aeróbica, y en menor grado el rendimiento a corto plazo y la fatiga muscular local. Por tanto, se recomienda su uso a los entrenadores de judo y a los monitores de entrenamiento físico como medida de supervisión de la potencia aeróbica, resaltando la necesidad de una prueba de campo que describa la potencia anaeróbica

Introduction: The purpose of this study was to assess the relationship between aerobic and anaerobic power, and special judo fitness test in elite male judokas. Method: Nineteen elite Judokas [age 24.3 (3.1) yr, height 1.78 (.06) m, body mass 76.4 (11.2) kg, body mass index 20.2 (3.6) kg•m-2 and body fat 11.0 (1.8)%] performed a graded exercise test in treadmill, the Wingate anaerobic test for arms and the special judo fitness test. The graded exercise test in treadmill estimated maximal oxygen uptake (VO2max) and the Wingate anaerobic test assessed peak and mean power, descriptors of short-term power output and local muscular endurance respectively. Results: The index of special judo fitness test was in inverse direct relationship with VO2max (r = -0.87, p < 0.01), peak power (r = -0.74, p < 0.01) and mean power (r = -0.62, p < 0.05). Discussion: Based on these findings, it was showed that the special judo fitness test is a field test that describes chiefly aerobic power, and in a lesser degree short-term power output and local muscular fatigue. Therefore, its further use from judo coaches and fitness trainers as a measure to monitor aerobic power is recommended, and the need for a field test that will describe anaerobic power is highlighted