Perovskite-type CaMn(1-x)Nb(x)O(3+/-delta) (x = 0.02, 0.05, and 0.08) compounds were synthesized by applying both a "chimie douce" (SC) synthesis and a classical solid state reaction (SSR) method. The crystallographic parameters of the resulting phases were determined from X-ray, electron, and neutron diffraction data. The manganese oxidations states (Mn(4+)/Mn(3+)) were investigated by X-ray photoemission spectroscopy. The orthorhombic CaMn(1-x)Nb(x)O(3+/-delta) (x = 0.02, 0.05, and 0.08) phases were studied in terms of their high-temperature thermoelectric properties (Seebeck coefficient, electrical resistivity, and thermal conductivity). Differences in electrical transport and thermal properties can be correlated with different microstructures obtained by the two synthesis methods. In the high-temperature range, the electron-doped manganate phases exhibit large absolute Seebeck coefficient and low electrical resistivity values, resulting in a high power factor, PF (e.g., for x = 0.05, S(1000K) = -180 microV K(-1), rho(1000K) = 16.8 mohms cm, and PF > 1.90 x 10(-4) W m(-1) K(-2) for 450 K < T < 1070 K). Furthermore, lower thermal conductivity values are achieved for the SC-derived phases (kappa < 1 W m(-1) K(-1)) compared to the SSR compounds. High power factors combined with low thermal conductivity (leading to ZT values > 0.3) make these phases the best perovskitic candidates as n-type polycrystalline thermoelectric materials operating in air at high temperatures.

Genetic variants underlying reduced male reproductive performance have been identified in humans and model organisms, most of them compromising semen quality. Occasionally, male fertility is severely compromised although semen analysis remains without any apparent pathological findings (i.e., idiopathic subfertility). Artificial insemination (AI) in most cattle populations requires close examination of all ejaculates before insemination. Although anomalous ejaculates are rejected, insemination success varies considerably among AI bulls. In an attempt to identify genetic causes of such variation, we undertook a genome-wide association study (GWAS). Imputed genotypes of 652,856 SNPs were available for 7962 AI bulls of the Fleckvieh (FV) population. Male reproductive ability (MRA) was assessed based on 15.3 million artificial inseminations. The GWAS uncovered a strong association signal on bovine chromosome 19 (P = 4.08×10−59). Subsequent autozygosity mapping revealed a common 1386 kb segment of extended homozygosity in 40 bulls with exceptionally poor reproductive performance. Only 1.7% of 35,671 inseminations with semen samples of those bulls were successful. None of the bulls with normal reproductive performance was homozygous, indicating recessive inheritance. Exploiting whole-genome re-sequencing data of 43 animals revealed a candidate causal nonsense mutation (rs378652941, c.483C>A, p.Cys161X) in the transmembrane protein 95 encoding gene TMEM95 which was subsequently validated in 1990 AI bulls. Immunohistochemical investigations evidenced that TMEM95 is located at the surface of spermatozoa of fertile animals whereas it is absent in spermatozoa of subfertile animals. These findings imply that integrity of TMEM95 is required for an undisturbed fertilisation. Our results demonstrate that deficiency of TMEM95 severely compromises male reproductive performance in cattle and reveal for the first time a phenotypic effect associated with genomic variation in TMEM95.

Controlled morphological and structural variations of LaTiO2N and CoO x nanoparticles loaded as a cocatalyst increased the photocatalytic O2 evolution. Four different LaTiO2N samples were prepared from two varied La2Ti2O7 precursors by thermal ammonolysis with and without flux. The most effective transformation from La2Ti2O7 into LaTiO2N in terms of crystallinity and nitrogen contents was obtained in the following two cases: flux-assisted ammonolysis of La2Ti2O7 characterized by a comparatively small particle size and a large surface area and ammonolysis without flux of highly crystalline La2Ti2O7. In both cases, high activity for O2 evolution under visible-light illumination (λ ≥ 420 nm) (∼50 μmol h–1) was obtained. Loading LaTiO2N with CoO x enhanced the photocatalytic activity for O2 evolution, although the effect of CoO x depended on the morphologies of LaTiO2N as a support. The promotional effect was most pronounced for LaTiO2N with a skeletal morphology, because such LaTiO2N contain most unsaturated bonds that act as nucleation centers that in turn generate small and highly dispersed CoO x nanoparticles.

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Semiconductor powders are perfectly suited for the scalable fabrication of particle-based photoelectrodes, which can be used to split water using the sun as a renewable energy source. This systematic study is focused on variation of the electrode design using LaTiO2 N as a model system. We present the influence of particle morphology on charge separation and transport properties combined with post-treatment procedures, such as necking and size-dependent co-catalyst loading. Five rules are proposed to guide the design of high-performance particle-based photoanodes by adding or varying several process steps. We also specify how much efficiency improvement can be achieved using each of the steps. For example, implementation of a connectivity network and surface area enhancement leads to thirty times improvement in efficiency and co-catalyst loading achieves an improvement in efficiency by a factor of seven. Some of these guidelines can be adapted to non-particle-based photoelectrodes.

Background: Lymphoceles (LC) represent a well-described rare complication post-radical prostatectomy (RP). Our aim was to determine risk factors and to develop possible prevention strategies for LC in a community-based study. Methods: Data from 1163 RP-patients from 67 clinics between January 2002 and December 2004 were retrospectively evaluated. Patients underwent pelvic imaging procedures/LC-management during 3 weeks of rehabilitation post-RP. Results: LC were identified in 304 patients (26%). Lymphadenectomy was carried out in 92% of patients (1001/1086 patients), from which 28% had LC (n = 277) versus 14% without lymphadenectomy (12/85, P = 0.007). Complications (lower limb edema, pain, thrombosis, infection and bladder compression) were observed in 9% of patients (28/304; 2.4% of total patients); necessitating therapy. LC therapy was carried out in 59 patients (5.9%) with pelvic lymph node dissection (PLND) and in no patients (0%) without PLND (P = 0.021). Risk factors included were patients' age, body mass index, prostate volume, TNM-classification, number of removed lymph nodes, previous surgery/therapy, heparin prophylaxis, surgical instruments and pelvic lymphadenectomy. Univariate analysis showed lymphadenectomy as the only significant risk factor for the development of LC post-RP (P = 0.007). When applying multivariate analyses using stepwise logistic regression, only lymphadenectomy was associated with a significant risk for lymphoceles (odds ratio = 2.6, 95% CI = 1.3-4.9, P = 0.004). Adjusting for other factors, no other factor came close to being significant (P < 0.05). All symptomatic LC were successfully treated without further sequelae. Conclusions: Subclinical LC post-RP are more common than thought, and rarely necessitate intervention. Pelvic lymphadenectomy represents the only significant factor contributing to LC-development. Because of this, prevention remains difficult.

Elevated estradiol levels are correlated with male infertility. Causes of hyperestrogenism include diseases of the adrenal cortex, testis or medications affecting the hypothalamus-pituitary-gonadal axis. The aim of our study was to elucidate the effects of estradiol treatment on testicular cellular morphology and function, with reference to the treatment regimen received. Testes samples (n = 9) were obtained post-orchiectomy from male-to-female transsexuals within the age range of 26–52 years. Each patient had a minimum of 1–6 years estradiol treatment. For comparison, additional samples were obtained from microscopically unaltered testicular tissue surrounding tumors (n = 7). The tissues obtained were investigated by stereomicroscopy, histochemistry, scanning electron microscopy (SEM) and immunohistochemistry. Our studies revealed that estradiol treatment significantly decreased the diameter of the seminiferous tubules (p < 0.05) and induced fatty degeneration in the surrounding connective tissue. An increase in collagen fiber synthesis in the extracellular matrix (ECM) surrounding the seminiferous tubules was also induced. Spermatogenesis was impaired resulting in mainly spermatogonia being present. Sertoli cells revealed diminished expression of estrogen receptor alpha (ERα). Both Sertoli and Leydig cells showed morphological alterations and glycoprotein accumulations. These results demonstrate that increased estradiol levels drastically impact the human testis.