Page 138 - ITU Journal Future and evolving technologies Volume 2 (2021), Issue 3 – Internet of Bio-Nano Things for health applications
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ITU Journal on Future and Evolving Technologies, Volume 2 (2021), Issue 3




          whose integration yields the closed-form solution:   biological reason.
                                                   2
                                   2
               (  ) =               [− ∫  (     +     +    [1 −  2 ])    ]
                            0                     
                                                      (    )
                       
          With    =     and by specifying the upper limit by
                         
          “T” the net charge that is transported by the bacteria
                                2
          with the change   (  ) =      +     +    [1 −     2 ], then Eq. 32
                                               2
          can be written in compact form as:
                                             
                       (  ,   ) =              [−    (  )].     (    )
                                          
          With  this  result,  now  the  electric  current  that   Fig.  4  –  The  instantaneous  current  as  a  function  of  radial
          involves  a  more  general  electric  description  of   distance (Eq.36), expressed in in arbitrary units. Two phases
          bacteria aggregation transporting ions is given by   can be perceived.
          the instantaneous derivative of Eq. 33 and written   Below  in  Fig.  5  the  simplest  scenario  of  Eq.  35
          as:                                                  written  as  I(t)=tExp(-t)  is  illustrated.  The
                                                               qualitative  shape  of  electric  current  indicates  its
                                         (  ,   )          
            (   =   ,   ) = −               [−    (  )].     (    )   maximal value. Clearly, it is directly interpreted as
                                               
                                                               the inverse scenario of Fig. 4 establishing a kind of
          On the other hand in the simplest case by which "  "   complementarity  with  it.  This  triggers  logic
          does not depend on time, then the integration over   scenario establishing that organization is first and
          the time variable inside the exponential in Eq. 32 is   disruption is after.
          trivial. In this manner the resulting electric current
          can be written in a simplified form as:
               (  )                               
                =   (  ) = −      (  )       [−    (  )].      (    )
                                               
          Actually the  variable  “  ” can be understood as the
          period  in  the  which  the  bacteria  aggregation
          behaves as an electric current.

          3.1  Biophysics  Interpretation  of  Electrical
          Currents
          Eq. 34 is  displayed in Fig. 4 exhibiting a minimum
          for     ≈     a.u.  For  this  plotting  it  was  used  as  a
          numerical expression for Eq. 34 in the form of:
                                                               Fig. 5 – RC Discharge: The instantaneous current and period of
                                          
              (   =   ,   ) =   .         (     +   .      +  )      [−  .     (  ^   +  electric interaction of bacteria as a function of radial distance,
                                       (  )^  
                                                               both expressed in in arbitrary units. This plot as well as Fig. 1,
                                   .        + (   −  ))].           (36)   Fig. 2, Fig. 3 and Fig. 4 were done with the usage of Wolfram
                                            (  )^  
                                                               [13].
          As indicated at Fig. 4, bacteria aggregation would
          exhibit a kind of disruption as seen in the minimum   In this manner, one can see that from Fig. 4 and Fig.
          value  of  current  distribution.  In  this  manner,  one   5 the possible existence of well-defined phases. This
          can wonder if it is an inherent property of bacteria   would characterize the BKS model. These possible
          aggregation or if it is a pure speculative theoretical   phases would emerge from the fact that the  Eq. 5
          result that might not be matched with experiments.   exhibits a kind of electric discharge as a RC-circuit.
          It should be noted that all these procedures have    It is in accordance to the negative exponential of Eq.
          been done under the assumption of a 1-Dimension      35. Therefore, bacteria aggregation and their social
          model.  Of  course,  realistic  simulations  might  be   manifestations  would  be  disrupted.  In  Fig.  5  the
          necessary in order to identify rupture of electrical   instantaneous  current  falls  down  as  a  fact  that
          properties.  As  done  in  [14],  memory-based       bacteria have “finshed” a social action leaving them
          chemotaxis would exibit drift velocities. So that one   to   break   down   the   possible   molecular
          can  argue  that  this  drift  dynamics  might  appear   communications between them.
          from  electric  phenomena  more  than  a  pure





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