From c32d1d5d501947e695df6445f51ea85951275417 Mon Sep 17 00:00:00 2001 From: "marcin p. joachimiak" <4625870+realmarcin@users.noreply.github.com> Date: Tue, 11 Aug 2026 07:21:12 -0700 Subject: [PATCH] The poise is a range, so it stays in electrode_detail (#183, #543) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Rifle_Aquifer_Bioanode_EET_Community: electroactive biofilms on anodes poised mostly at -0.2 to -0.25 V vs SHE, maintained for almost four years, acetate as the sole carbon source. The electrode is the growth surface that selects this community, not a probe applied to it — both the biofilm and the planktonic fraction were sampled off it. applied_potential is deliberately unset. The source gives a range and qualifies it with "mostly", so a single number would assert a poise the four-year run did not hold. The range lives in electrode_detail instead. That field is also where the reference electrode belongs, which is the call made in #517 when applied_potential_unit was narrowed to {V, mV}: a potential is only meaningful against its reference, "vs SHE" is not a unit, and keeping the reference in prose is what allows a range to be stated at all rather than compressed into a value plus a suffix. First real instance of that decision paying for itself. Confirms the second "likely curatable" prediction in #543 — a bioanode implies an electrochemical cell, and the biofilms were established and maintained rather than sampled from the aquifer. Co-Authored-By: Claude Opus 5 --- .../Rifle_Aquifer_Bioanode_EET_Community.yaml | 35 +++++++++++++++++++ 1 file changed, 35 insertions(+) diff --git a/kb/communities/Rifle_Aquifer_Bioanode_EET_Community.yaml b/kb/communities/Rifle_Aquifer_Bioanode_EET_Community.yaml index a056f10c..de5b40d5 100644 --- a/kb/communities/Rifle_Aquifer_Bioanode_EET_Community.yaml +++ b/kb/communities/Rifle_Aquifer_Bioanode_EET_Community.yaml @@ -280,6 +280,41 @@ ecological_interactions: in the Rifle aquifer that may have the potential to mediate mineral redox transformations explanation: Supports the selective enrichment of EET-capable organisms. +cultivation_setup: +- system_type: BIOELECTROCHEMICAL_SYSTEM + instrument_detail: >- + Electroactive biofilms grown on poised anodes and maintained for almost four years, with + acetate as the sole carbon source. Both the anode biofilm and the planktonic fraction + were sampled, so the electrode is not merely a probe - it is the growth surface that + selects the community this record describes. + electrode_detail: >- + Anodes poised mostly at -0.2 to -0.25 V versus the standard hydrogen electrode, a range + chosen to mimic the redox potential of iron-oxide minerals. + notes: >- + `applied_potential` is left unset and the value kept in `electrode_detail`. The source + gives a range rather than a setpoint, and qualifies it with "mostly", so a single number + would assert a poise the four-year run did not hold. + + This is also the case #517 anticipated: the potential is only meaningful against its + reference electrode, and "vs SHE" is not a unit. Keeping the reference in + `electrode_detail` is what lets the range be stated in full rather than compressed into + a value-plus-suffix. + + No temperature or working volume - the source characterises the communities and does not + restate the reactor's dimensions. + + Predicted curatable in #543 on the grounds that a bioanode implies an electrochemical + cell, and it is: the biofilms were established and maintained rather than sampled from + the aquifer directly. + evidence: + - reference: PMID:32849356 + supports: SUPPORT + evidence_source: IN_VITRO + snippet: Electroactive biofilms were established and maintained for almost 4 years on anodes + poised mostly at -0.2 to -0.25 V vs. SHE, a range that mimics the redox potential of + iron-oxide minerals, using acetate as the sole carbon source + explanation: The electrode poise and its reference, the duration, and the sole carbon source. + environmental_factors: - name: Anode redox potential value: -0.2 to -0.25 V vs SHE