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The article presents a study which aims to determine the life histories and life-cycle strategies of some invertebrates in intermittent streams in Hawke's Bay, New Zealand. The study was conducted from March 2005 to May 2007 in three different sites and used samples of various benthic macroinvertebrates including mayflies, caddisflies, and Potamopyrgus antipodarum snail. Results show that intermittent sites has more taxa, plurivoltine life cycles, and asexual reproduction than perennial sites.

The article presents a study which evaluates the biodiversity values of several headwater streams located in Auckland region of New Zealand. It mentions that the three habitat headwaters which include flowing water, isolated pool, and wet mud have the same density of aquatic macroinvertebrates with near perennial streams. Richness of ephemeroptera, plecoptera, and trichoptera is the same in flowing water, isolated pools, and perennial stream.

Background: The genetic control of sex determination in teleost species is poorly understood. This is partly because of the diversity of mechanisms that determine sex in this large group of vertebrates, including constitutive genes linked to sex chromosomes, polygenic constitutive mechanisms, environmental factors, hermaphroditism, and unisexuality. Here we use a de novo genome assembly of New Zealand silver trevally (Pseudocaranx georgianus) together with sex-specific whole genome sequencing data to detect sexually divergent genomic regions, identify candidate genes and develop molecular makers., Results: The de novo assembly of an unsexed trevally (Trevally&#95;v1) resulted in a final assembly of 579.4 Mb in length, with a N50 of 25.2 Mb. Of the assembled scaffolds, 24 were of chromosome scale, ranging from 11 to 31 Mb in length. A total of 28,416 genes were annotated after 12.8 % of the assembly was masked with repetitive elements. Whole genome re-sequencing of 13 wild sexed trevally (seven males and six females) identified two sexually divergent regions located on two scaffolds, including a 6 kb region at the proximal end of chromosome 21. Blast analyses revealed similarity between one region and the aromatase genes cyp19 (a1a/b) (E-value < 1.00E-25, identity > 78.8 %). Males contained higher numbers of heterozygous variants in both regions, while females showed regions of very low read-depth, indicative of male-specificity of this genomic region. Molecular markers were developed and subsequently tested on 96 histologically-sexed fish (42 males and 54 females). Three markers amplified in absolute correspondence with sex (positive in males, negative in females)., Conclusions: The higher number of heterozygous variants in males combined with the absence of these regions in females support a XY sex-determination model, indicating that the trevally&#95;v1 genome assembly was developed from a male specimen. This sex system contrasts with the ZW sex-determination model documented in closely related carangid species. Our results indicate a sex-determining function of a cyp19a1a-like gene, suggesting the molecular pathway of sex determination is somewhat conserved in this family. The genomic resources developed here will facilitate future comparative work, and enable improved insights into the varied sex determination pathways in teleosts. The sex marker developed in this study will be a valuable resource for aquaculture selective breeding programmes, and for determining sex ratios in wild populations., (© 2021. The Author(s).)

Objective: This study investigates knee joint arthroplasty and compares the outcomes between attending (consultant) orthopedic surgeons and resident (trainee) surgeons., Design: Retrospective review and comparison of knee joint arthroplasty outcomes between 4 surgeon groups (attending, supervised senior and junior residents, and unsupervised senior residents). Measured outcomes were implant survival (revision rate) and patient reported functional outcomes, measured by Oxford knee score (OKS)., Setting: New Zealand arthroplasty service., Participants: Seventeen years of knee joint arthroplasty data from the New Zealand Joint Registry (NZJR) was reviewed., Results: The New Zealand Joint Registry (NZJR) data showed 79,671 total knee arthroplasties (TKA) and 8854 unicompartmental knee arthroplasties (UKA) performed between 1999 and 2016. Attending surgeons performed 90% and 97% of TKA and UKA, respectively. The number and proportion of resident performed knee joint arthroplasty has decreased. Faster operation times was observed in the attending surgeon group. Attending surgeon revision rate was 0.49 and 1.19/100 component years for TKA and UKA, respectively, this was not significantly increased in resident surgeon groups. Postoperative OKS was 37.7 and 39.7 for attending surgeon performed TKA and UKA, respectively. Mean OKS were less than 2 points worse in resident groups (resident range: 36.3-36.9) compared to attending colleagues for TKA, but for UKA scores were up to 11 points worse (resident range: 28.9-38.8)., Conclusions: New Zealand has a high rate of attending surgeon performed TKA and UKA. Revision rates were not increased in resident surgeon groups. Postoperative function was not reduced by a clinically significant amount in TKA in any of the resident surgeon groups but was reduced in supervised junior resident and unsupervised senior resident surgeon groups for UKA., (Copyright © 2018 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.)