Elementary Principals\u27 Follow-Through in Teacher Evaluation to Improve Instruction

Author\u27s abstract: Today, school administrators view teacher evaluation as a way to improve instruction and remove mediocre teachers from the system; however, while much is teacher evaluation, there is still much to learn. This study explored how school principals being written about employed follow-through with teacher evaluation systems for the purpose of increased student learning. This study makes both theoretical and practical contributions to the fields of education and school leadership. This was a qualitative study, using semi-structured interviews, focus groups, and a thorough review of the teacher evaluation documents in a small county in Georgia as the method of data collection. Purposeful sampling of tenured teachers, from all four elementary schools in one county, was used to select participants for the focus groups. The four elementary principals from the same four schools were interviewed as well as the county office administrator in charge of teacher evaluations. An open coding method of analysis was used to analyze and interpret the data. Four broad categories of themes emerged from the data to address the research questions: (a) Leaders\u27 beliefs about follow-through to teacher evaluation, (b) Teachers\u27 beliefs about follow-through to teacher evaluation, (c) Strategies to improve evaluation and follow-through, and (d) Policies and procedures must be clear and current for follow-through to occur. Several conclusions were drawn from the findings: (1) Principals consider teacher evaluation of low performing teachers an important part of their job description. (2) Principals implement strategies related to structure, time, and opportunities. (3) High performing teachers rarely received valuable feedback on teacher evaluations that lead to improved instruction. (4) Most teachers had extreme emotions towards teacher evaluations; they either feared them or felt validated by them, there were few emotions in between. (5) Principals who were dedicated to the follow-through of teacher evaluation procedures had teachers who were more likely to be comfortable about the process. (6) Principals implement a variety of strategies to manage the time consuming challenges of teacher evaluation. (7) County policies need to change to include current standards-based evaluation methods. (8) Traditional formal evaluations do not adequately measure instruction. (9) Because teachers felt they learn better from observing other teachers, there should be a requirement for peer evaluation built into the system

It is currently unknown whether SARS-CoV-2 is viable in semen or whether COVID-19 damages sperm.

© 2020 American Society of Andrology and European Academy of Andrology Research is needed to understand the presence of the SARS-CoV-2 virus in semen, sexual transmissibility, and impact on sperm quality. Several studies have examined men recovering from COVID-19, but large-scale community-based testing is needed to ascertain the effects on the male reproductive tract, and the potential for prolonged transmission

Archaeal Tuc1/Ncs6 Homolog Required for Wobble Uridine tRNA Thiolation Is Associated with Ubiquitin-Proteasome, Translation, and RNA Processing System Homologs

<div><p>While cytoplasmic tRNA 2-thiolation protein 1 (Tuc1/Ncs6) and ubiquitin-related modifier-1 (Urm1) are important in the 2-thiolation of 5-methoxycarbonylmethyl-2-thiouridine (mcm⁵s²U) at wobble uridines of tRNAs in eukaryotes, the biocatalytic roles and properties of Ncs6/Tuc1 and its homologs are poorly understood. Here we present the first report of an Ncs6 homolog of archaea (NcsA of <i>Haloferax volcanii</i>) that is essential for maintaining cellular pools of thiolated tRNA^Lys_UUU and for growth at high temperature. When purified from <i>Hfx. volcanii</i>, NcsA was found to be modified at Lys204 by isopeptide linkage to polymeric chains of the ubiquitin-fold protein SAMP2. The ubiquitin-activating E1 enzyme homolog of archaea (UbaA) was required for this covalent modification. Non-covalent protein partners that specifically associated with NcsA were also identified including UbaA, SAMP2, proteasome activating nucleotidase (PAN)-A/1, translation elongation factor aEF-1α and a β-CASP ribonuclease homolog of the archaeal cleavage and polyadenylation specificity factor 1 family (aCPSF1). Together, our study reveals that NcsA is essential for growth at high temperature, required for formation of thiolated tRNA^Lys_UUU and intimately linked to homologs of ubiquitin-proteasome, translation and RNA processing systems.</p></div

Model of NcsA activity and sampylation (panel A) as well as its association with protein partners (panel B).

<p>Panel A, NcsA is proposed to catalyze the formation of 2-thiouridine (s²U) at the wobble uridine position of tRNAs specific for lysine (tRNA^Lys_UUU), glutamate (tRNA^Glu_UUC), and glutamine (tRNA^Gln_UUG) via an adenylated tRNA intermediate using thiocarboxylated SAMP2 as a source of activated sulfur. The E1-like UbaA adenylates the C-terminal α-carboxylate group of SAMP2. This modification readies the Ub-fold SAMP2 for either thiocarboxylation via an enzyme (cysteine desulfurase or rhodanese) catalyzed persulfide sulfur or protein modification via formation of a UbaA-SAMP2 thioester intermediate. Polymeric chains of SAMP2 are formed on an NcsA lysine residue via isopeptide linkages that are cleaved by HvJAMM1 protease. Whether additional factors are needed to provide specificity to the sampylation system is unclear, as E2 and E3 homologs are not predicted based on genome sequence. Panel B, NcsA is found isopeptide linked to SAMP2 and non-covalently associated with various proteins, as noted by dotted red lines. NcsA partners include the E1-like UbaA and Ub-fold SAMP2 of the tRNA thiolation and sampylation pathways. NcsA is also found associated with EF-1α that binds aminoacylated-tRNAs and mediates translation elongation, PAN-A/1 (an AAA+ATPase associated with energy-dependent proteolysis by proteasomes (20S core particles or CPs) and protein remodeling, and the β-CASP ribonuclease homolog of the aCPSF1 family thought to cleave mRNA and/or tRNA. RNAP, RNA polymerase.</p

HvJAMM1 (desampylase) collapses SAMP2-NcsA conjugates.

<p>NcsA-StrepII fractions were purified from <i>ΔncsA</i> and <i>ΔubaA</i> strains, incubated with HvJAMM1 in the presence and absence of EDTA, and analyzed by IB as indicated. Molecular weight markers are indicated to the left of each blot. Pull down assays were from 1 L cultures. See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0099104#s4" target="_blank">Methods</a> section for details.</p

Multiple amino acid sequence alignment of <i>Hfx. volcanii</i> NcsA (HVO_0580) with ANH superfamily members including proteins of <i>Saccharomyces cerevisiae</i> (ScNcs6, GI:50593215), <i>Homo sapiens</i> (HsNcs6, GI:74713747), <i>Pyrococcus horikoshii</i> (PH1680, GI:14591444; PH0300, GI:14590222), <i>Thermus thermophilus</i> (TTHA0477 or TtuA, GI: 55980446), <i>Salmonella typhimurium</i> (StTtcA, GI:16764998), and <i>Escherichia coli</i> (EcTtcA, GI:85674916).

<p>Conserved residues are highlighted in red, grey and black, with the conserved residues in red of the ATP pyrophosphatase signature PP-motif (SGGXDS) involved in ATP binding (Bork and Koonin, 1994) as well as motifs CXXC and GHXXDD (which act to recognize RNA) present in the TtcA protein family (Jager et al., 2004). Zinc fingers are highlighted in blue boxes, ubiquitin-fold modified lysine residues are in red boxes, and conserved catalytic cysteine residues are indicated by a star. Secondary structural elements predicted for HVO_0580 based on Phyre2 3D homology modeling are highlighted with blue arrows (β-sheets) and green cylinders (α-helices) above the amino acid sequence.</p

Proteins Identified by LC-MS/MS proteomic analysis^a.

a<p>MS-identified proteins with coverage above 25% are reported according to the <i>Hfx. volcanii</i> gene locus tag from the National Center for Biotechnology Information and were unique to samples prepared from strain <i>ΔncsA</i> expressing the FLAG-tagged SAMP1 in tandem with StrepII-tagged NcsA, FLAG-tagged SAMP2 in tandem with StrepII-tagged NcsA, or StrepII-tagged NcsA alone compared to the vector alone. Theoretical molecular mass (M_r) estimated from deduced polypeptide based on <i>Hfx. volcanii</i> DS2 genome sequence.</p

NcsA is covalently associated with SAMP2 through a UbaA-dependent mechanism.

<p>A) NcsA StrepII-affinity purified fractions purified from <i>ΔncsA</i> strains expressing NscA-StrepII with and without Flag-SAMP1/2 proteins were separated by reducing SDS-PAGE and analyzed by Coomassie blue stain (upper panel) and α-StrepII and α-Flag IB (middle and bottom panels, respectively) as indicated. B) α-StrepII immunoblot of NcsA-StrepII purified from H26 (wt, parent), <i>ΔubaA</i>, and <i>Δsamp2</i>. C) α-Flag immunoblot of NcsA-StrepII purified from H26 (wt, parent) and <i>ΔubaA</i> strains co-expressing Flag-SAMP2. Molecular weight markers are indicated to the left of each blot. Pull down assays were from 1 L cultures. See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0099104#s4" target="_blank">Methods</a> section for details.</p

NcsA is required for growth of <i>Hfx. volcanii</i> at an elevated temperature (50°C).

<p><i>Hfx. volcanii</i> H26 (wt, parent), <i>Δsamp2</i>, <i>ΔncsA</i>, and <i>trans</i> complemented <i>ΔncsA</i> strains were grown in ATCC 974 medium. Freshly isolated colonies were inoculated into 3 ml medium (in 13×100 mm culture tubes) and thrice subcultured at 42°C. Cells grown to logarithmic phase at 42°C from these subcultures were used as inoculum for monitoring growth at 50°C as presented in panel A. Cells grown to stationary-phase from these 50°C cultures were used as an inoculum for monitoring long-term growth at 50°C as presented in panel B. Inoculum was at 0.02 OD₆₀₀ with rotary shaking (200 rpm) in 20 ml medium in 250 ml baffled flasks for the growth assays presented in panels A and B. For panel C, cell cultures, as indicated above each plate, were diluted to 0.1 OD₆₀₀ and then spot-plated on solid agar ATCC 974 medium in serial dilutions as indicated. Plates were incubated at 50°C. Control experiments performed at 42°C are presented in Figure S4 in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0099104#pone.0099104.s001" target="_blank">File S1</a>. See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0099104#s4" target="_blank">Methods</a> section for details.</p