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Since 2008, the Chinese American Chromatography Association (CACA) has hosted career development workshops at Pittcon, featuring over 65 well-established pharmaceutical, biotechnology, and contract research organizations, and academia professionals. This year's workshop featured five speakers, all of whom shared valuable insights and advice for individuals at different stages of their careers, including graduate students, early-career professionals, high-level managers, and aspiring entrepreneurs., For young separation scientists, one of the significant challenges in career development is finding the ideal job to pursue their dreams. This task can be particularly daunting for foreign-born scientists [...]

Aims To provide valuable information for a comprehensive understanding of the multicellular behavior of Bacillus velezensis Bs916 regulated by surfactin and other natural signals by Transcriptome. Methods and results Transcriptomics revealed a distinct effect on gene expression alterations caused by disruption of the surfactin gene cluster(Δ srf) and 100 µg/ml surfactin addition(Δ srf  + SRF). A total of 1573 differential expression genes were identified among Bs916, Δ srf , and Δ srf  + SRF and grouped into eight categories based on their expression profiles. RT-qPCR analysis of 30 candidate genes showed high consistency with those of transcriptome. Additionally, the expression of eight candidate genes regulated by surfactin in a dose-dependent manner was revealed by lacZ fusion. Based on the above evidence, we proposed that surfactin can act as an extracellular signal for monitoring biofilm formation in Bs916 by directly regulating the expression of AbrB, DegS-degU, and SinI-SinR, and indirectly regulating the phosphorylation of ComA and Spo0A. Conclusions The biofilm of Δ srf was unable to restore significantly by surfactin addition, combined inclusion of surfactin (SRF), exopolysaccharide (EPS), and γ-poly- dl -glutamic acid (γ-PGA), results in significant restoration of Δ srf biofilm formation, thereby a preliminary model was presented about the molecular mechanism by which the signaling molecule surfactin regulates Bs916 multicellular behavior. [ABSTRACT FROM AUTHOR]

Research has been conducted on the soluble C (sub)60 -(pi-conjugated oligomer) dyads. The synthesis of these dyads has been carried out and the results indicate that in the resulting electro- and photoactive dyads the singlet-singlet energy transfer and the intramolecular electron transfer compete with each other in the photoexcited oligomer deactivation.

Research has been conducted on the fulleropyrrolidine triads. The results of the synthesis, electrochemical characterization and photoinduced electron-transfer studies of these triads are described.

The results of nanosecond and picosecond laser flash photolysis studies of C120 are reported.

Steady-state spectroscopic methods were used to investigate the thermal equilibrium of radical ion in electron-transfer reactions between tetrakis(dimethylamino)ethylene and fullerenes (C60 and C70) in the ground and excited states. Results indicated that the radical ions take different solvated forms that depend on the solvent polarity. The combination of the equilibrium data with the kinetic data revealed that the electron transfer rate constants in the excited state are larger than those in the ground state.

Photoinduced electron-transfer reactions of pyrrolidinofullerenes {C60(C3H6R)R; R = H (1), C6H4NO2-p (2), C6H4CHO-p (3), C6H5 (4), C6H4OMe-p (5) and C6H4NMe2-p (6)} with N,N-dimethylaniline were systematically investigated by nanosecond laser photolysis. Results showed that the triplet excited states of pyrrolidinofullerenes can accept an electron from dimethylaniline in the proper polar solvents.

Fullerene amino derivatives were synthesized by thermal and photochemical reactions of amino acid ester with C60. The derivative C60(Me2CHNHCHCOOEt) was formed by refluxing the glycine ethyl ester and C60 solution whereas irradiation of the same mixture resulted to C60(EtOOCCHNHCHCOOEt). On the other hand, photochemical reactions between C60 and sarcosine esters produced the pyrrolidine derivatives C60(CH2N(Me)CHCOOR) and C60(ROOCCHNHCHCOOR) (R = Me, Et, CH2Ph).

Metal-chelating properties in the ground and excited states of fullerenocalix[4]arenes containing two malonamide substituents at the upper rim and four alkyl esters at the lower rim are studied by means of steady-state absorption, fluorescence spectroscopy, and time-resolved transient absorption spectra. No, spectroscopic evidence was obtained for nay influence caused by Mn2+, although the malonamide groups provide good cheating ability even for the transition metal ion.

Molecular modeling studies reveal that the lowest energy conformation of the dyad is the structure in which the porphyrin moves over to the side of the fullerene sphere, bringing the two pie systems into close proximity. It was concluded that charge separation in hybrid systems occurs through space in unsymmetrical conformations, where the center-to-center distance between the component pie systems is minimized.

Research has been conducted on C (sub)60 /exTTF linkages (exTTF= 9,10-bis(1,3-dithiol-2-ylidene)-9,10-dihydroanthracene). The authors describe the effects produced by these linkages via anthracene unit or via dithiole ring.

The beneficial role of a zwitterionic fulleropyrrolidinium acceptor, that is, acceleration of charge separation and deceleration of charge recombination is demonstrated. Overall, the reorganization energies for the fulleropyrrolidinium based ensemble that are smaller than those seen for the fulleropyrrolidine- based analogue, while keeping the electronic coupling element constant are determined.

Inspired complex function of photosynthesis light harvest by the antenna ensemble, transduction of excitation energy to photosynthetic reaction center and charge separation thereafter, numerous artificial model systems are devised. Most common problem in artificial model system is the lack of efficient solar light capture, because of insufficient chromophore activity.