A new chrysochlorid from Makapansgat

Main articleIn this paper a new species of golden mole Chrysotricha hamiltoni sp. nov. from Limeworks, Makapansgat, is described. This is the first occurrence of a fossil golden mole at this site; two fossil forms (Proamblysomus antiquus Broom and Chlorotalpa spelea Broom) have previously been recorded from Sterkfontein.Non

A preliminary investigation of the mammalian microfauna in Pleistocene deposits of caves in the Transvaal system

Main articleThis investigation aims to extend our knowledge of the fossil mammalian microfauna found in the Australopithecus-bearing breccias of the Transvaal System at Taung, Sterkfontein and Makapansgat. The available data derived from other localities such as Kromdraai and Bolt's Farm have been incorporated. The origin of these fossils, the method of extraction from the breccias, and a brief review of the geological nature of the deposits under consideration are discussed.Non

Histone modification during the induction of tyrosine transaminase

"The induction phenomenon is a useful model for the study of mechanisms which regulate the synthesis of specific enzymes in mammalian tissue, as well as for the role of hormones in this process". The in vivo administration of hormone initiates a chain of reactions which culminate in the increase of protein synthesis. Many hepatic enzymes are thus affected resulting in an increase of their activity. Studies of the giant chromosomes in the salivary glands of Chironomus tentans provided the first indications that the earliest intracellular effects of hormone administration are at the genetic level. Injection of the insect moulting hormone, ecdysone, into last instar larvae of Chironomus tentans results in puff formation at specific loci of the chromosomes shortly after hormone administration. Since puffs are local and reversible alterations of the chromosome, formed at sites which are active in the synthesis of informational RNA, their formation shows a change in activity of particular gene loci in response to ecdysone

Anaerobic Treatment of Concentrated Black Water in UASB Reactor at a Short HRT

This research describes the feasibility of applying a UASB reactor for the treatment of concentrated black (toilet) water at 25 °C. On average 78% of the influent load of COD at an HRT of 8.7 days was removed. Produced methane can be converted to 56 MJ/p/y as electricity and 84 MJ/p/y as heat by combined heat and power (CHP). Minimum reactor volume at full scale was calculated to be 63L per person (for black water containing 16 gCOD/L produced at 5 L/p/d) and this is more than two times smaller than other type of reactors for anaerobic treatment of concentrated black wate

Higher return to pre-injury type of sports after revision anterior ligament reconstruction with lateral extra-articular tenodesis compared to without lateral extra-articular tenodesis

PurposeTo evaluate the rate of return to pre-injury type of sports (RTS type) in patients after revision anterior cruciate ligament reconstruction (ACLR) with lateral extra-articular tenodesis (LET) compared to patients after revision ACLR without LET.MethodsSeventy-eight patients who underwent revision ACLR with an autologous ipsilateral bone-patellar tendon-bone autograft with and without LET were included at least one year after surgery (mean follow-up: 43.9, SD: 29.2 months). All patients filled in a questionnaire about RTS type, the Knee injury and Osteoarthritis Outcome Score (KOOS), the International Knee Documentation Committee subjective form (IKDCsubjective), and the Tegner activity score.ResultsThe RTS type for revision ACLR with LET was 22 of 42 (52%), whereas 11 of 36 (31%) of the patients who underwent revision ACLR without LET returned to the pre-injury type of sport (p = 0.05). No significant differences were found in KOOS subscores, IKDCsubjective, and Tegner activity scores.ConclusionAn additional LET increases the rate of RTS type after revision ACLR

Structure of trans-bis[4-amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole-N1,N'[diaqua- manganese(II) dibromide

[Mn(C12H10N6)2(H2O)2]Br2, Mr = 727.28, orthorhombic, Pbca, a = 10.734 (6), b = 17.084 (0), c = 15.182 (6) angstrom, V = 2784 angstrom 3, Z = 4, D(x) = 1.734 g cm-3, lambda-(Mo K-alpha) = 0.71073 angstrom, mu = 33.23 cm-1, F(000) = 1450, T = 295 K, final R = 0.032 for 1493 reflections [I > 2-sigma(I)]. The title compound is the first reported mononuclear compound with the ligand 4-amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole. The manganese ions, situated on an inversion centre, are coordinated by four nitrogen atoms with an N-Mn-N angle of 74.1 (1)-degrees and Mn-N distances of 2.188 (4) and 2.266 (4) angstrom. Two axial water molecules [Mn-O = 2.200 (4) angstrom] complete the coordination sphere of the metal, which is pseudo-octahedral. The two bromide ions are not coordinated but are involved in an extended hydrogen-bridging network with the water ligands and the amino group of the triazole

Living and working in ethnic enclaves: Language proficiency of immigrants in US metropolitan areas

Learning English is a potentially profitable investment for immigrants in the U.S.: while there are initial costs, the subsequent benefits include the ability to communicate with the majority of the population, potentially leading to better paying jobs and economic success in the new country. These payoffs are lessened if immigrants choose to live and work in ethnic enclaves where the necessity to communicate in English is weak. Ethnic enclaves are widespread and persistent in the U.S. This study uses data from the 2010 American Community Survey to examine the impact of residential and occupational segregation on immigrants' ability to speak English. We allow for heterogeneity in the relationship between segregation and English language proficiency across ethnic groups and focus specifically on Mexican and Chinese immigrants. Our results show that immigrants in the U.S. who live and work among high concentrations of their countrymen are less likely to be proficient in English than those who are less residentially and occupationally segregated. The magnitude of the effect of segregation on language proficiency varies across immigrants' birthplaces and other salient characteristics defining the immigration context

Automatic Max-Likelihood Envelope Detection Algorithm for Quantitative High-Frame-Rate Ultrasound for Neonatal Brain Monitoring

Objective: Post-operative brain injury in neonates may result from disturbed cerebral perfusion, but accurate peri-operative monitoring is lacking. High-frame-rate (HFR) cerebral ultrasound could visualize and quantify flow in all detectable vessels using spectral Doppler; however, automated quantification in small vessels is challenging because of low signal amplitude. We have developed an automatic envelope detection algorithm for HFR pulsed wave spectral Doppler signals, enabling neonatal brain quantitative parameter maps during and after surgery. Methods: HFR ultrasound data from high-risk neonatal surgeries were recorded with a custom HFR mode (frame rate = 1000 Hz) on a Zonare ZS3 system. A pulsed wave Doppler spectrogram was calculated for each pixel containing blood flow in the image, and spectral peak velocity was tracked using a max-likelihood estimation algorithm of signal and noise regions in the spectrogram, where the most likely cross-over point marks the blood flow velocity. The resulting peak systolic velocity (PSV), end-diastolic velocity (EDV) and resistivity index (RI) were compared with other detection schemes, manual tracking and RIs from regular pulsed wave Doppler measurements in 10 neonates. Results: Envelope detection was successful in both high- and low-quality arterial and venous flow spectrograms. Our technique had the lowest root mean square error for EDV, PSV and RI (0.46 cm/s, 0.53 cm/s and 0.15, respectively) when compared with manual tracking. There was good agreement between the clinical pulsed wave Doppler RI and HFR measurement with a mean difference of 0.07. Conclusion: The max-likelihood algorithm is a promising approach to accurate, automated cerebral blood flow monitoring with HFR imaging in neonates.</p