Chirp-driven control over fast-slow light effects in epsilon-near-zero metamaterials.

Optical applications based on fast and slow light effects force the usage of metamaterials famous for their flexible dispersion properties. In this work, we apply the unique optical nonlocality of metal nanorod-based epsilon-near-zero (ENZ) metamaterials along with the chirp of femtosecond laser pulses for astonishing control of these effects. We demonstrate the switching between the fast and slow light phenomena via the change of the angle of incidence and/or the central wavelength of chirped pulses in the vicinity of metamaterial zero-transmission regime mediated by the ENZ nonlocality. We elucidate that the laser chirp allows one to manipulate and enhance the fast-slow light phenomena.

[Age changes in spermogram and fertilizing capacity of spermatosides in persons 26-47 years old.]

The work is devoted to the analysis of age-related changes in human spermatozoa and their functional properties in men aged 26-47 years. The work used ejaculate obtained from 54 men as part of the in vitro fertilization procedure. The patients were divided into three groups (26-29, 30-34 and over 35 years old). In the course of the work, the parameters of the spermogram were collected, as well as the results of assessing the viability of spermatozoa, obtained using the method of flow cytometry, and also a retrospective analysis of the effectiveness of in vitro fertilization was carried out. It was found that the average values of spermogram parameters in groups were within the physiological norm, however, about 59% of patients had individual deviations in terms of 1-3 indicators. Cytometric analysis revealed a rapid increase with age in functional disorders of spermatozoa, affecting the recognition and penetration apparatus (acrosome), the energy apparatus of the cell (its mitochondrion) and the density of chromatin in its nucleus. The result is a decrease in the probability of fertilization from 88% at 26-29 years old to 61% after 35 years, even with in vitro fertilization. The significance of the results obtained for the analysis of age-related changes in the male reproductive system and the practice of treating male infertility is substantiated.

Long-term outcomes of ruxolitinib therapy in steroid-refractory graft-versus-host disease in children and adults.

Acute and chronic steroid-refractory graft-versus-host disease (srGVHD) is a life-threatening complication of allogeneic stem cell transplantation. There are a number of reports on case series describing efficacy of ruxolitinib in both acute and chronic srGVHD. We conducted a prospective study (NCT02997280) in 75 patients with srGVHD (32 acute, 43 chronic, 41 adults, and 34 children). Patients with chronic GVHD had severe disease in 83% of cases, and acute GVHD patients had grade III-IV disease in 66% of cases. The overall response rate (ORR) was 75% (95% CI 57-89%) in acute GVHD and 81% (95% CI 67-92%) in chronic. Overall survival was 59% (95% CI 49-74%) in acute group and 85% (95% CI 70-93%). The major risk factors for lower survival were grade III-IV gastrointestinal involvement (29% vs 93%, p = 0.0001) in acute form and high disease risk score in chronic (65% vs 90%, p = 0.038). Toxicity was predominantly hematologic with 79% and 44% of grade III-IV neutropenia in acute and chronic groups, respectively. There was no difference between adults and children in terms of ORR (p = 0.31, p = 0.35), survival (p = 0.44, p = 0.12) and toxicity (p > 0.93). The study demonstrated that ruxolitinib is an effective option in acute and chronic srGVHD and can be used both in adults and children.