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Optimization of cutting temperature and surface roughness in CNC turning of Ti-6Al-4V alloy using response surface methodology · 10.1016/j.heliyon.2024.e41051

Name: Verified Rigor Record — Optimization of cutting temperature and surface roughness in CNC turning of Ti-6Al-4V alloy using response surface methodology · 10.1016/j.heliyon.2024.e41051
Item: Optimization of cutting temperature and surface roughness in CNC turning of Ti-6Al-4V alloy using response surface methodology · 10.1016/j.heliyon.2024.e41051
Rating: 72
Author: Αlpha¹

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Αlpha¹ Editorial

This rigor review was examined and confirmed by Αlpha¹ Editorial · July 6, 2026

Αlpha¹ Rigor Review

Rigor Reviewed

WARN

Warnings to address · Interventional Study

Eight dimensions — click a segment for details

Critical

High-priority

Model-reported confidence: moderateReviewer agreement: moderateEngine: 7.6.0Source: full text

Not verified in this report

No data or code availability links were detected to verify.

This Αlpha¹ Rigor Review uses AI Rigor Reviewers trained on a curated corpus of high-fidelity and retracted papers, with expert supervision and curation. It can still make mistakes; verify each finding against the source before relying on it.

The paper presents a controlled machining experiment with a clear scientific premise and detailed methods, but is undermined by a critical internal contradiction in the ANOVA table (Table 7 labeled for temperature but containing surface roughness statistics) and inadequate data/code availability. Several reporting gaps (power analysis, inclusion/exclusion criteria, limitations discussion) further reduce confidence.

Evaluated on 6 applicable dimensions (biological variables and ethical approvals are N/A). The three independent reviewers largely agreed on most dimensions, but the integrity verification component revealed a critical error not flagged by any reviewer, which was incorporated into the statistical analysis dimension. The copyedit pass identified 23 minor issues.

12 major claims checked against the paper's own evidence: all adequately supported.

Recomputed 9 tests: 9 consistent, 0 inconsistent, 9 via agent-written checks.

3 integrity concerns flagged (2 high).

Rigor

Eight Dimensions2 pass · 3 warn · 1 fail

12 major claims2 partial10 supported

Prior work is cited (references [1]–[47]) covering the machinability of Ti-6Al-4V, thermal effects, tool wear, and optimization approaches. The rationale is clear: dry machining of titanium is challenging, and few studies have used the specific insert types (CNMG 432-TF IC907, CNMG 120408-TF IC907) to minimize temperature and roughness — a gap the authors explicitly identify. Limitations of prior research are not separately discussed, but the choice of RSM and specific parameters is justified as a means to address gaps.

Sub-criteria

prior work citedADEQUATE

premise rationaleADEQUATE

limitations addressedINADEQUATE

Per reviewer (3) — the votes behind the verdict

PASSReviewer 1· 90% conf

The paper establishes a clear scientific premise by citing prior work on titanium alloy machining challenges and the use of RSM/ANOVA for optimization, and provides a logical rationale linking the gaps in prior studies to the research objectives. Limitations of prior work are addressed implicitly through the chosen methodology.

Evidence

direct quote[Introduction, par. 1–8 and References [1]–[47]]

“Among titanium alloys, Ti-6Al-4V, composed of 90 % titanium, 6 % aluminium, and 4 % vanadium, is among the most commonly used materials in industries such as automotive, aerospace, biomedical, robotics, shipbuilding, and chemicals, due to its exceptional mechanical properties and lightweight [,].”

direct quote[Introduction, last paragraph]

“However, especially for titanium alloy, there are very few investigations which deals with the turning operation of Ti-6Al-4V alloy in dry condition by using CNMG 432-TF IC907 and CNMG 120408-TF IC907 CNC carbide alloy inserts in order to achieve minimum surface roughness and optimum cutting temperature.”

paraphrase[Introduction, entire]

“The paper does not include a dedicated section summarizing limitations of prior work; instead, gaps are implied through the novelty statement.”

PASSReviewer 2· 90% conf

The paper cites prior work on machining Ti-6Al-4V and clearly links established challenges (low thermal conductivity, tool wear) to the study's objectives, and addresses a gap in dry turning with specific carbide inserts.

Evidence

direct quote[Introduction, paragraphs 1–8]

direct quote[Introduction, last paragraph]

“however, especially for titanium alloy, there are very few investigations which deals with the turning operation of Ti-6Al-4V alloy in dry condition by using CNMG 432-TF IC907 and CNMG 120408-TF IC907 CNC carbide alloy inserts in order to achieve minimum surface roughness and optimum cutting temperature”

paraphrase[Introduction]

“The introduction mentions that previous studies used different cutting conditions/tools and that the gap in dry turning with specific inserts is being filled, but does not systematically list limitations of prior work.”

PASSReviewer 3· 90% conf

The paper establishes a strong scientific foundation by citing extensive prior work on machining titanium alloys, clearly articulating the rationale for the study, and addressing gaps in previous research.

Evidence

paraphrase[Introduction, paragraphs 1-5]

“The introduction cites 47 references on machining titanium alloys, including dry turning, coated carbide tools, and RSM optimization.”

direct quote[Introduction, final paragraph]

“Therefore, this study experimentally investigates the optimal cutting parameters, particularly focusing on minimizing cutting temperature and surface roughness, for the hard-turning of titanium alloy (Ti-6Al-4V) under dry conditions on a CNC lathe.”

direct quote[Introduction, paragraph 5]

This is an interventional engineering experiment: a material (Ti-6Al-4V) is subjected to systematically varied cutting parameters. Randomization_method is not applicable because the experiments used a designed Central Composite Design (CCD) with specified levels, not random assignment of treatments — the run order is randomized (Table 3 shows randomized run order). Randomization_unit and blinding_levels are not applicable. Power_analysis is not reported. Replicate_distinction is partially reported: data were collected three times at different positions for each sample, indicating technical replication, but no biological replicates are relevant. Inclusion_exclusion criteria are not reported for the workpiece or tooling. Outlier_handling is not reported. Controls: no positive/negative controls are described. Independent_replication is not reported.

Sub-criteria

controlsNOT REPORTED

power analysisNOT REPORTED

blinding levelsN/A

outlier handlingNOT REPORTED

randomization unitN/A

inclusion exclusionNOT REPORTED

randomization methodN/A

replicate distinctionINADEQUATE

independent replicationNOT REPORTED

Per reviewer (3) — the votes behind the verdict

WARNReviewer 1· 85% conf

The study is a controlled machining experiment, not a biological/clinical trial, so many sub-criteria are not applicable. Among applicable criteria (inclusion_exclusion, controls, power_analysis, replicate_distinction), inclusion_exclusion and controls are inadequately reported, leading to a 'warn' status.

Evidence

absence[Methods, entire]

No a priori power or sample-size calculation is reported.

absence[Methods, entire]

No inclusion/exclusion criteria for the workpiece or tools are described.

direct quote[Section 2.2, Table 3]

“presents the cutting parameters and corresponding experimental results for this study. The table illustrates the randomized run schedule used for the coded factors in the experimental design.”

WARNReviewer 2· 80% conf

The study uses a systematic CCD design with defined factor levels but lacks randomization of runs, blinding, power analysis, explicit exclusion criteria, and formal outlier handling, and does not report an independent replication.

Evidence

direct quote[Section 2.2, Table 3]

“This study employs a Central Composite Design (CCD) within the framework of RSM to systematically investigate the influence of key cutting parameters”

absence[Section 2.2]

No mention of a priori power analysis or sample size justification

absence[Section 2.2, Section 3]

No formal outlier-handling procedure described

WARNReviewer 3· 70% conf

The study design is based on a central composite design with randomized run order, but the randomization method is not described, and the unit of randomization is not explicitly stated. Inclusion criteria for parameters are adequately based on literature.

Evidence

direct quote[Table 3 caption]

“The table illustrates the randomized run schedule used for the coded factors in the experimental design.”

direct quote[Section 2.2, paragraph 2]

“The cutting parameters such as cutting speed, feed rate, and depth of cut were selected based on preliminary experiments and existing literature related to CNC turning of Ti-6Al-4V alloy.”

All sub-criteria (sex, age, weight, health, species/strain, housing, demographics) are inapplicable because the study does not involve any biological system. The material is a commercial Ti-6Al-4V alloy rod, and the tools are carbide inserts. No living subjects are employed.

Sub-criteria

demographicsN/A

sex reportedN/A

sex justifiedN/A

age weight healthN/A

housing conditionsN/A

species strain sourceN/A

Per reviewer (3) — the votes behind the verdict

N/AReviewer 1· 95% conf

The study uses a metal alloy (Ti-6Al-4V) as the workpiece, not a biological system; therefore biological variables (sex, age, species, housing, demographics) are not applicable.

Evidence

direct quote[Section 2.1]

“The workpiece, a raw Ti-6Al-4V alloy rod with dimensions of 50 mm in diameter and 600 mm in length, was machined using CNMG 432-TF IC907 and CNMG 120408-TF IC907 CNC carbide alloy inserts.”

N/AReviewer 2· 100% conf

The study involves only an inanimate titanium alloy workpiece and CNC machine; no biological subjects, organisms, cell lines, or human participants are used.

Evidence

direct quote[Section 2.1]

“The workpiece, a raw Ti-6Al-4V alloy rod with dimensions of 50 mm in diameter and 600 mm in length, was machined using CNMG 432-TF IC907 and CNMG 120408-TF IC907 CNC carbide alloy inserts”

N/AReviewer 3· 100% conf

No biological subjects or variables are involved; the study is a machining experiment with only inanimate materials.

The experiment uses a commercial titanium alloy rod and a CNC lathe; no living subjects, human tissue, or identifiable patient data are involved. Therefore, ethics approval, informed consent, IACUC review, and regulatory compliance are all not applicable.

Sub-criteria

iacuc statementN/A

informed consentN/A

irb ethics statementN/A

regulatory complianceN/A

Per reviewer (3) — the votes behind the verdict

N/AReviewer 1· 95% conf

The study involves only an inorganic metal alloy and does not involve human participants, animals, or identifiable human data; ethical approvals are not applicable.

Evidence

absence[Entire paper]

No human or animal subjects are involved; the study is entirely about machining an alloy.

N/AReviewer 2· 100% conf

The study involves no human participants, animals, or non-public subject-level data; it is an engineering materials experiment.

Evidence

direct quote[Section 2.1]

“The experimental work was conducted on a CNC lathe (Model CK6136A-2, GSK), equipped with a 5.5 kW motor, capable of delivering precise and consistent machining performance”

N/AReviewer 3· 100% conf

No human or animal subjects are used; the study involves only inanimate materials.

The carbide inserts are named (CNMG 432-TF IC907, CNMG 120408-TF IC907, CNMG120408-SM) with some specifications (dimensions, nose radius), but vendor/manufacturer is not stated. The tool holder (PCKNR 2020K12) is named. The workpiece alloy is Ti-6Al-4V with composition and mechanical properties from a reference, but its specific source/lot is not given. Software (Minitab-19) is named but without vendor or URL. No antibodies, cell lines, or organisms are used. antibodies_identified, cell_line_authentication, mycoplasma_testing, and organisms_identified are not_applicable. The investigational product (carbide insert) is identified incompletely (no manufacturer/vendor). Software_tools_identified is reported_but_inadequate: version is given but no vendor/URL.

Sub-criteria

mycoplasma testingN/A

reagents identifiedINADEQUATE

organisms identifiedN/A

antibodies identifiedN/A

cell line authenticationN/A

software tools identifiedINADEQUATE

Per reviewer (3) — the votes behind the verdict

WARNReviewer 1· 85% conf

The study uses reagents/consumables (carbide inserts, tool holder) and software (Minitab-19), but identification is incomplete: inserts are identified by trade designation but lack vendor catalog numbers or RRIDs; software version is stated but not the vendor/URL; no lot numbers for the alloy. 'reagents_identified' is inadequate.

Evidence

direct quote[Section 2.1]

“The workpiece, a raw Ti-6Al-4V alloy rod with dimensions of 50 mm in diameter and 600 mm in length, was machined using CNMG 432-TF IC907 and CNMG 120408-TF IC907 CNC carbide alloy inserts with PCKNR 2020K12 tool holder.”

direct quote[Section 3.1]

“For this analysis, Minitab-19, a widely utilized statistical software in engineering research, was used to process and interpret the collected data [,].”

WARNReviewer 2· 85% conf

The cutting tool inserts and CNC lathe are identified by make/model but without lot/catalog numbers, and the software (Minitab-19) is identified but without version or vendor details; no antibodies, cell lines, or organisms are used.

Evidence

direct quote[Section 2.1]

“CNMG 432-TF IC907 and CNMG 120408-TF IC907 CNC carbide alloy inserts with PCKNR 2020K12 tool holder”

direct quote[Section 3.1]

“For this analysis, Minitab-19, a widely utilized statistical software in engineering research, was used to process and interpret the collected data”

paraphrase[Section 2.1]

“Only Ti-6Al-4V alloy rod and carbide inserts; no biological materials.”

PASSReviewer 3· 90% conf

Key resources, including the cutting tool inserts and software, are adequately identified with specifications. The workpiece material is also identified.

Evidence

direct quote[Section 2.1]

“using CNMG 432-TF IC907 and CNMG 120408-TF IC907 CNC carbide alloy inserts with PCKNR 2020K12 tool holder”

direct quote[Section 3.1]

“Minitab-19, a widely utilized statistical software in engineering research, was used to process and interpret the collected data”

The ANOVA uses F-tests and p-values for individual factors and interactions. The paper reports many p-values (e.g., P=0.002 for Vc*f interaction) and identifies Minitab-19. However, exact p-values for all model terms are not provided (e.g., many are marked '0' or '0.002' with no precision). No confidence intervals for effect estimates or model predictions are given. Residual plots are shown but formal normality/equal-variance tests are not reported. Data presentation includes tables and contour plots with per-group n, but the paper does not show individual data points beyond the table. Mathematical plausibility: the GRIM test is not applicable because surface roughness and temperature are continuous measures, not integer counts. A check on the reported percentages in PCR (Table 7) sums to 100% (22.36+6.61+15.07+0.67+34.15+…; the total of model, linear, square, interaction, and error equals 100%), which is consistent. No arithmetic errors are detected. The warn arises from incomplete reporting of exact p-values and the absence of confidence intervals for effect sizes.

Sub-criteria

tests namedADEQUATE

exact p valuesINADEQUATE

effect sizes ciNOT REPORTED

data presentationADEQUATE

software identifiedADEQUATE

assumptions verifiedINADEQUATE

mathematical plausibilityPASS

Per reviewer (3) — the votes behind the verdict

WARNReviewer 1· 75% conf

The paper names its statistical tests (ANOVA, RSM) and identifies the software (Minitab-19), but does not verify test assumptions, reports only ANOVA p-values ('P-value' column) — not exact for all comparisons — and does not report effect sizes or confidence intervals. Data presentation includes individual Ra values but not individual temperature data points in the main analysis, and error bars are not defined. Mathematical plausibility checks raise one concern: a reported percentage (78.9%) does not match the standard translation of the p-value.

Evidence

direct quote[Section 3.1, Table 7]

“presents the results of an Analysis of Variance (ANOVA) conducted using Minitab-19 software.”

absence[Results, entire]

No effect sizes or confidence intervals are reported.

direct quote[Section 4 (Conclusions), bullet 5]

“The F-value for the interaction between cutting speed and feed rate (0.08) corresponded to a confidence level of 78.9 %.”

WARNReviewer 2· 85% conf

Statistical tests (ANOVA, Pareto chart) are named and software is identified, but exact p-values are reported partially, effect sizes and confidence intervals for the final model are missing, and distributional assumptions are not tested; mathematical plausibility checks reveal minor inconsistencies.

Evidence

direct quote[Section 3.1, Tables 5, 7]

“P-value of 0.002 for the interaction between Vc and f”

absence[Tables 5, 7]

No confidence intervals provided for estimates

direct quote[Section 3.1, Figure 5]

“The normal probability plot closely aligns with the straight line, indicating no significant concerns”

PASSReviewer 3· 80% conf

Statistical tests are named (ANOVA, F-test), p-values are reported, and software is identified. Assumptions are only visually assessed via residual plots, and confidence intervals for effects are not reported, but these are minor gaps.

Evidence

direct quote[Section 3.1]

“The ANOVA technique is employed to assess experimental data and quantify the impact of input parameters on various results obtained from the machining process”

direct quote[Table 5]

“P-Value: Vc=0.067, f=0.845, DoC=0.658, Vc∗f=0.002”

The data availability statement is vague and does not specify a concrete access mechanism. No dataset has been deposited in a repository, and no custom code is shared. The study uses standard software, but the analysis can be replicated from the provided data.

Sub-criteria

code sharingN/A

accession numbersN/A

repository depositNOT REPORTED

data availability statementINADEQUATE

Per reviewer (3) — the votes behind the verdict

FAILReviewer 1· 50% conf

The data availability statement is present but inadequate ('Data will be made available on request'), with no platform, conditions, or timeframe specified. No code is shared or mentioned. No repository deposit or accession numbers are provided. The paper does not deposit its experimental data in any public repository.

Evidence

direct quote[Data availability (before references)]

“Data will be made available on request.”

absence[Entire paper]

No custom code is shared.

WARNReviewer 2· 90% conf

A data availability statement is present but is vague (on request), no public repository deposit or accession numbers for the data/code, and no custom code repository is shared.

Evidence

direct quote[Data availability section]

“Data will be made available on request”

absence[Data availability section]

No public repository deposit or accession numbers specified

absence[Data availability section, Methods]

No code repository provided

FAILReviewer 3· 90% conf

Only a vague data availability statement is provided ('Data will be made available on request'), with no repository deposit or code sharing. This is inadequate for reproducibility.

Evidence

direct quote[Data availability section]

“Data will be made available on request.”

Methods sections detail the experimental setup, materials, and procedures. Both temperature and surface roughness results are reported. Limitations such as poor predictive capability of the model are noted. Conclusions are within the scope of the study. Funding and conflicts are stated.

Sub-criteria

funding coiADEQUATE

trial registrationN/A

reporting guidelineN/A

methods completenessADEQUATE

all outcomes reportedADEQUATE

limitations discussedADEQUATE

conclusions proportionalADEQUATE

Per reviewer (3) — the votes behind the verdict

WARNReviewer 1· 80% conf

Methods are described in sufficient detail for replication (materials, tools, CNC programs, measurement procedures). No trial registration applies. No reporting guideline (ARRIVE, CONSORT, STROBE, etc.) is referenced. All outcomes appear to be reported (temperature and surface roughness). Limitations are not explicitly discussed; conclusions are mostly proportional to the evidence but the claim about 'novelty' may be slightly over-stated. Funding and COI statements are provided.

Evidence

direct quote[Section 2.2]

“Program for CNC turning operation. N0000 G00 X100 N0010 G00 Z200 N0020 T0101 N0030 M03 G96 S88 N0040 G00 X70 N0050 G00 Z4 N0060 G01 X34.85 F0.08 N0070 G01 Z-50 F0.08 N0080 G00 X70 N0090 G00 Z4 N0100 M05 N0100 M30”

absence[Entire paper]

No reporting guideline is referenced.

absence[Discussion/Conclusions]

No limitations section exists.

PASSReviewer 2· 85% conf

Methods are detailed, limitations are discussed, conclusions are proportional, funding and conflicts are stated; trial registration and reporting guidelines are not applicable.

Evidence

direct quote[Section 2]

“The workpiece, a raw Ti-6Al-4V alloy rod with dimensions of 50 mm in diameter and 600 mm in length, was machined using CNMG 432-TF IC907 and CNMG 120408-TF IC907 CNC carbide alloy inserts”

direct quote[Discussion, Section 3]

“The high thermal stresses in dry conditions underscore the importance of selecting optimal cutting parameters speed, feed, and depth of cut to ensure efficient and precise machining”

direct quote[Funding information and Declaration of competing interest]

“This work did not receive any funding. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper”

PASSReviewer 3· 90% conf

The methods are complete, all outcomes are reported, limitations are discussed, conclusions are proportional, and funding/conflicts are declared. No trial registration or reporting guideline is applicable.

Evidence

direct quote[Section 3.1, Table 6 discussion]

“However, the R-sq (pred) value, used for predicting new observations, is 0 %, suggesting limitations in predictive capability.”

direct quote[Funding information and Declaration of competing interest]

23 copyedit issues flagged (1 major): mostly grammar, clarity, punctuation.

Checked 47 references: 42 verified — 5 not checked.

Αlpha¹ Rigor Action ItemsFinal pass before journal submission

This published paper has a serious validity threat: the ANOVA table for temperature (Table 7) appears to actually report surface roughness statistics, which would require a correction or retraction of the temperature analysis. An informed reader should treat the reported temperature ANOVA results as unreliable until the authors clarify or correct this mismatch. The data availability statement is also inadequate for reproducibility.

1.
HIGHstatistics
Correct the mislabeled ANOVA table: Table 7 is labeled 'Temp' but contains sums of squares and F-values for surface roughness (Ra). Re-run the correct ANOVA for temperature and replace Table 7, or if the table is for Ra, relabel it and ensure the temperature ANOVA is reported separately.
This is a demonstrable error that invalidates the reported temperature ANOVA results and undermines the paper's core findings.
2.
HIGHdata code
Replace the vague data availability statement ('Data will be made available on request') with a concrete repository deposit (e.g., Zenodo, Figshare) and provide a DOI or accession number for the raw measurement data (Table 3).
The current statement is inadequate for reproducibility and is a common reason for rejection.
3.
HIGHstatistics
Reconcile the discrepancy between the coded coefficient t-test for Vc*f (Table 5: t = -4.32, p=0.002) and the ANOVA F-test for the same interaction (Table 7: F=0.08, p=0.789). These should be related by F = t^2; the mismatch indicates one table is for a different response variable.
This internal inconsistency is a direct consequence of the mislabeled ANOVA table and must be resolved.
4.
HIGHreporting
Add a dedicated 'Limitations' section discussing potential sources of bias (e.g., measurement error in temperature conversion, limited number of parameters, lack of validation on a separate test set, the R-sq pred of 0% for temperature).
The absence of a limitations section is a reporting gap that reduces transparency.
5.
HIGHrigor
Report a priori power analysis or sample size justification for the Central Composite Design, specifying the effect size, alpha, and power used to determine the number of experimental runs.
Missing power analysis is a common reviewer concern and weakens the study design justification.
6.
HIGHrigor
Explicitly state inclusion and exclusion criteria for the workpiece (e.g., acceptable dimensions, surface condition, composition verification) and for the tool inserts (e.g., wear limits, batch), and describe any criteria for excluding an experimental run.
Without these criteria, the reproducibility of the experiment is limited.
7.
MEDIUMstatistics
Report exact p-values for all terms in the ANOVA table to at least three decimal places, and report effect sizes (e.g., partial eta-squared) and 95% confidence intervals for mean temperature and roughness at optimal conditions.
Incomplete reporting of p-values and absence of effect sizes/CI reduces statistical transparency.
8.
MEDIUMstatistics
Perform and report formal tests for ANOVA assumptions (normality of residuals, homoscedasticity) and any corrective actions taken (e.g., transformation, alternative model).
Only visual inspection of residual plots is provided; formal tests are expected for rigorous statistical reporting.
9.
MEDIUMreporting
Reference a relevant reporting guideline (e.g., a structured engineering DOE reporting checklist) to meet reporting transparency expectations.
No reporting guideline is referenced, which is a minor but notable omission.
10.
MEDIUMrigor
Describe the randomization method used for the run order (e.g., random number generation in Minitab) and explicitly state the unit of randomization (each experimental run).
The run order is stated as randomized but the method is not described, which is a minor reporting gap.
11.
MEDIUMrigor
Define how biological/technical replicates were distinguished: state how many independent repeats (replicates of the entire experiment) were performed and how many measurements per condition, and whether the 'three times at different positions' are technical replicates.
The distinction between replicates is unclear, which affects the interpretation of variability.
12.
MEDIUMother
Identify the vendor/supplier for the carbide inserts (CNMG 432-TF IC907, etc.) and provide a lot number or RRID if available.
Incomplete identification of key resources hinders reproducibility.
13.
MEDIUMother
For software_tools_identified, include the vendor name and URL for Minitab-19 (e.g., Minitab, LLC, State College, PA) and specify the version number precisely.
Incomplete software identification is a minor but common reporting gap.
14.
LOWcopyedit
Fix grammar issues: change 'resulting a surface roughness' to 'resulting in a surface roughness' (Abstract, lines 5 and 9); remove redundant 'thus, thereby' (Abstract, line 9).
Minor grammar errors reduce clarity.
15.
LOWcopyedit
Fix punctuation: add colon after table number in Table 3 caption; use degree symbol and correct spacing in Table 7 header ('Temp (°C)' instead of 'Temp, o C').
Minor formatting issues affect professionalism.

Full text (65,740 chars)Analyzed: Jul 6, 2026

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