Reflections on the COVID-19 Pandemic

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Anatomic Aspects of Inguinal Lymph Nodes Applied to Lymphadenectomy in Penile Cancer

Objectives. To provide a better understanding of the distribution of inguinal nodes in order to prevent the complications of unnecessary and extended dissections in penile cancer. Methods. The bilateral inguinal regions of 19 male cadavers were dissected. Nodal distribution was noted and quantified based on anatomical location. The superficial nodes were subdivided into quarters as follows: superomedial, superolateral, inferomedial, and inferolateral. Statistical analysis was performed comparing node distribution between quarters using one-way analysis of variance (ANOVA), and the unpaired T-test was used between superficial and deep nodes. Results. Superficial nodes were found in all inguinal regions studied (mean = 13.60), and their distribution was more prominent in the superomedial quarter (mean = 3.94) and less in the inferolateral quarter (mean = 2.73). There was statistical significance between quarters when comparing the upper group with the lower one (P = 0.02). Nodes were widely distributed in the superficial region compared with deep lymph nodes (mean = 13.60 versus 1.71, P < 0.001). Conclusions. A great number of inguinal lymph nodes are distributed near the classical anatomical landmarks for inguinal lymphadenectomy, more prominent in upper quadrants

Nutrient cycling in sugarcane. III. Nutrient contents and root distribution in the soil

Determinaram-se a matéria seca e os teores de macro e micronutrientes do sistema radicular de cana-de-açúcar (Saccharum officinarum L.) num experimento sem e com aplicação de 60 kg.ha-1 de N, em solo Podzólico Vermelho-Amarelo, textura arenosa, na Unidade de Execução de Pesquisa (UEP) de ltapirema (Goiana, PE). Após 3, 6, 11 e 16 meses do plantio foram recolhidas, por peneiramento, todas as raízes, colmos subterrâneos e rebolos de um volume de 1 m3 de solo, em triplicata, tendo 0,8 m de comprimento ao longo do sulco, 1 m de profundidade (subdividido de 0,2 m em 0,2 m) e 1,25 m de largura. Somente houve diferenças entre tratamentos com e sem N com relação às massas de raízes aos seis e dezesseis meses de idade. A matéria seca atingiu um máximo de 6,5 t.ha-1 aos onze meses, sendo que 30% - 40% correspondiam a raízes. Toda a massa de colmos e rebolos e 75% da massa de raízes concentravam-se nos 0,2 m superficiais. As quantidades de nutrientes contidas na parte subterrânea foram pequenas em relação à parte aérea, atingindo aproximadamente 22, 2, 9, 6 e 4 kg.ha-1 de N, P, K, Ca e Mg e 80, 50 e 30 g.ha-1 de Zn, Mn e Cu, respectivamente.Sugarcane root biomass and its nutrient content were measured in a field experiment with two nitrogen treatments (no nitrogen, and 60 kg.ha-1 of N) on a sandy Red-Yellow Podzolic soil at the Unidade de Execução de Pesquisa (EUP) at Itapirema (Goiana, PE, Brazil). Roots, underground stems and seed cuttings were collected separately 3, 6, 11 and 16 months after planting by sieving 1 m3 of soil, in triplicate, being 0,8 m along the furrow, 1 m deep (subdivided each 0,2 m) and 1,25 m wide. The only significant differences between N treatments occurred in relation to the root weights at the 6 and 16 month samplings. Total underground weight reached a maximum of 6,5 t.ha-1 at the eleven month sampling, 30% - 40% of it corresponding to root weight. All the stems and seed cuttings plus 75% of the total root mass were found in the 0 cm - 20 cm layer. The amounts of nutrients in the underground parts were small compared to those of the aboveground parts, reaching a maximum of 22, 2, 9, 6 and 4 kg.ha-1 of N, P, K, Ca and Mg and 80, 50, and 30 g.ha-1 of Zn, Mn, and Cu, respectively

Aging in a Two-Dimensional Ising Model with Dipolar Interactions

Aging in a two-dimensional Ising spin model with both ferromagnetic exchange and antiferromagnetic dipolar interactions is established and investigated via Monte Carlo simulations. The behaviour of the autocorrelation function $C(t,t_w)$ is analyzed for different values of the temperature, the waiting time $t_w$ and the quotient $\delta=J_0/J_d$, $J_0$ and $J_d$ being the strength of exchange and dipolar interactions respectively. Different behaviours are encountered for $C(t,t_w)$ at low temperatures as $\delta$ is varied. Our results show that, depending on the value of $\delta$, the dynamics of this non-disordered model is consistent either with a slow domain dynamics characteristic of ferromagnets or with an activated scenario, like that proposed for spin glasses.Comment: 4 pages, RevTex, 5 postscript figures; acknowledgment added and some grammatical corrections in caption

Impact Assessment of Urethral Meatus Morphology and Penile Biometry in Transurethral Prostate and Bladder Surgery

Objective. To analyze the penile and urethral meatus biometry and its correlation with meatoplasty during endoscopic resections. We also propose a new classification for urethral meatus morphology. Materials and Methods. We prospectively studied 105 patients who underwent prostate and bladder transurethral resections. We performed standardized measurement of penile and urethral meatus biometry followed by penile photo in the front position. The need to perform meatoplasty or dilatation during resectoscope introduction was registered. Data were analyzed comparing the correlation between two groups: without intervention (Group A) and with intervention (Group B). Results. We observed in Group A and Group B, respectively, the average length of urethral meatus of 1.07 cm versus 0.75 cm (p<0.001) and average width of urethral meatus of 0.59 cm versus 0.38 cm (p<0.001). Considering the morphology of the urethral meatus, we propose a new classification, in the following groups: (a) typical; (b) slit; (c) point-like; (d) horseshoe; and (e) megameatus. The point-like meatus was the one that most needed intervention, followed by the slit and the typical meatus (p<0.001). Conclusions. Point-like and slit-shaped urethral meatus, as well as reduced length and width of the urethral meatus, are the determining factors

Evidence of exactness of the mean field theory in the nonextensive regime of long-range spin models

The q-state Potts model with long-range interactions that decay as 1/r^alpha subjected to an uniform magnetic field on d-dimensional lattices is analized for different values of q in the nonextensive regime (alpha between 0 and d). We also consider the two dimensional antiferromagnetic Ising model with the same type of interactions. The mean field solution and Monte Carlo calculations for the equations of state for these models are compared. We show that, using a derived scaling which properly describes the nonextensive thermodynamic behaviour, both types of calculations show an excellent agreement in all the cases here considered, except for alpha=d. These results allow us to extend to nonextensive magnetic models a previous conjecture which states that the mean field theory is exact for the Ising one.Comment: 10 pages, 4 figure