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This paper covers developments from International Embryo Technology Society (IETS) meetings over the past 50 years. The IETS was officially 'born' at a meeting in Denver, Colorado on Sunday 26 May 1974. There have been 51 IETS meetings (the first was in May 1974), and the first conference at which papers were presented was in 1975. The name of the IETS was changed from International Embryo Transfer Society to International Embryo Technology Society in 2016. The annual IETS conferences are held once a year in January. Embryo technology advanced from the laborious and slow techniques of surgical recovery and transfer of bovine embryos to non-surgical recovery and transfer in many species. Cryopreservation of embryos was initially a slow process that met with only moderate technical success before the development of technology that resulted in high embryo survival rates. The polymerase chain reaction was used to determine the sex of embryos following laminar flow cytology, which came into use to separate X- and Y-bearing spermatozoa. IVF has grown to become widely used, and several factors make it more useful than superovulation and embryo recovery/transfer. Perhaps the most important tool of all was the system that allowed the genetic 'mapping' of the genomic sequence of Bos taurus cattle. Charting key DNA differences by scientists, 'haplotypes' are now used routinely to identify animals with desirable traits of economic importance, discover new genetic disorders, and track carrier status of genotyped animals. Future technology is discussed. This paper deals with the 50-year history of embryo transfer technology. It covers the formation of the International Embryo Technology Society, a group of scientists and veterinarians who study or work in the field of embryos and the animals that produce them. These embryos can be frozen, moved from animal to animal, maintained outside the female, and modified by a number of procedures. Photograph by Jenson. [ABSTRACT FROM AUTHOR]

Lanthanide atoms show long magnetic lifetimes because of their strongly localized 4 f electrons, but electrical control of their spins has been difficult because of their closed valence shell configurations. We achieved electron spin resonance of individual lanthanide atoms using a scanning tunneling microscope to probe the atoms bound to a protective insulating film. The atoms on this surface formed a singly charged cation state having an unpaired 6 s electron, enabling tunnel current to access their 4 f electrons. Europium spectra display a rich array of transitions among the 54 combined electron and nuclear spin states. In contrast, samarium's ground state is a Kramers doublet with a very large g -factor of 5. These results demonstrate that all-electronic sensing and control of individual lanthanide spins is possible for quantum devices and spin-based electronics by using their rarely observed monovalent cation state.

To overcome the numerous challenges for the miniaturization of complementary metal–oxide–semiconductor (CMOS) technology, diverse materials have been examined using various characterization methods. Inelastic electron tunneling spectroscopy (IETS) has been regarded as a critical measurement technique to scrutinize materials. This is because the high sensitivity of IETS can provide important information regarding the material structures and molecular compositions (bonding structures, impurities, defects, and traps) in metal–oxide–semiconductor (MOS) structures, as well as the molecular conformation/isomerization, and contact geometry in molecular devices. This review introduces the background of IETS and recent applications of IETS on thin gate dielectrics, large DNA molecules, functional molecules, and diatomic molecules. [ABSTRACT FROM AUTHOR]

The adsorption behavior of single CO molecules at 4 K bound to Au adatoms on a Ag(001) metal surface is studied with scanning tunneling microscopy (STM) and inelastic electron tunneling spectroscopy (IETS). In contrast to earlier observations two different binding configurations are observed—one on top of a Au adatom and the other one adsorbed laterally to Au on Ag(001). Moreover, IETS reveals different low-energy vibrational energies for the two binding sites as compared to the one for a single CO molecule bound to Ag(001). Density functional theory (DFT) calculations of the adsorption energies, the diffusion barriers, and the vibrational frequencies of the CO molecule on the different binding sites rationalize the experimental findings. [ABSTRACT FROM AUTHOR]

On etwat, etwuk and iets: geography and dynamics of the indefinite pronoun (for things) in West-Flanders This paper focuses on the geography and dynamics of indefinite pronoun variants in West-Flanders (Belgium). Whereas traditional dialect data show etwat ('something') as being the traditional West-Flemish dialect variant, recent studies have attested a new variant in the area: etwuk. This paper addresses the questions (1) where this new dialect variant is used, (2) by whom, (3) how it relates to other variants of the indefinite pronoun and to the interrogative pronoun variants and (4) whether the grammatical context in which it occurs is of any influence. To answer these questions, we analyse 10.000 surveys collected in 2018 in 249 West-Flemish locations. Given that a sample of this size is difficult to analyse using traditional dialectological methods, we introduce generalized additive mixed-effects regression as a means of simultaneously analyzing the diatopic, diastratic and diachronic variation in these surveys (cf. Wieling et al. 2014:689). These generalized additive mixed-effects models reveal striking dynamics in the pronominal system in West-Flanders: the variant etwuk is clearly taking over the role of etwat as dialectal indefinite pronoun, with the region of the cities Ieper and Poperinge as 'expansion tank'. The rise of the non-standard pronoun etwuk is remarkable, given that Flanders is generally marked by dialect shift and dialect levelling (usually in favour of the standard language). We will argue that the pronominal changes in West-Flanders can be interpreted as a sign of linguistic glocalisation, with etwuk as means of indexing regional identity in times of homogenizing informal language use. [ABSTRACT FROM AUTHOR]

Abstract The objectives of this study were to determine (i) whether Chlamydia (C.) abortus would adhere to the intact zona pellucida (ZP-intact) of early in vitro produced bovine embryos; (ii) whether the bacteria would adhere to the embryos (ZP-free) after in vitro infection; and (iii) the efficacy of the International Embryo Transfer Society (IETS) washing protocol. The experimentation was made twice. For each replicate 100 (8–16-cell) bovine embryos produced in vitro were randomly divided into 10 batches. Height batches (4 ZP-intact and 4 ZP-free) of 10 embryos were incubated in a medium containing 4 × 107 Chlamydia /ml of AB7 strain. After incubation for 18 h at 37 °C in an atmosphere of 5% CO 2 , the embryos were washed in accordance with the IETS guidelines. In parallel, two batches (1 ZP-intact and 1 ZP-free) of 10 embryos were subjected to similar procedures but without exposure to C. abortus as a control group. The 10 washing fluids from each batch were collected and centrifuged for 1 h at 13,000× g. Each batch of washed embryos and each wash pellets were tested using PCR. C. abortus DNA was found in all ZP-intact and ZP-free batches of 10 embryos after 10 successive washes. For ZP-intact infected embryos, Chlamydia -DNA was also detected in all 10 wash baths for two batches (2/8) of embryos, whereas for ZP-free infected embryos, Chlamydia -DNA was detected in all 10 wash baths for 6/8 batches of embryos. In contrast, none of the embryos or their washing fluids in the control batches was DNA positive. The bacterial load for batches of 10 embryos after the 10 wash baths was significantly higher for batches of ZP-free embryos (20.7 ± 9 × 103 bacteria/mL) than for batches of ZP-intact embryos (0.47 ± 0.19 × 103 bacteria/mL). These results demonstrate that C. abortus adheres to the ZP as well as the early embryonic cells of in vitro produced bovine embryos after in vitro infection, and that the standard washing protocol recommended by the IETS fails to remove it. Highlights • C. abortus adheres to the intact zona pellucida and to the early embryonic cells. • standard washing protocol recommended by the IETS failed to remove it • Finding of C. abortus DNA by PCR did not imply that the bacteria found was infectious. [ABSTRACT FROM AUTHOR]

We show that Sarnak's conjecture on Möbius disjointness holds for interval exchange transformations on three intervals (3-IETs) that satisfy a mild diophantine condition. [ABSTRACT FROM AUTHOR]

Electron tunneling spectroscopy measurements on van der Waals heterostructures consisting of metal and graphene (or graphite) electrodes separated by atomically thin hexagonal boron nitride tunnel barriers are reported. The tunneling conductance, dI/dV, at low voltages is relatively weak, with a strong enhancement reproducibly observed to occur at around ∣V∣ ≈ 50 mV. While the weak tunneling at low energies is attributed to the absence of substantial overlap, in momentum space, of the metal and graphene Fermi surfaces, the enhancement at higher energies signals the onset of inelastic processes in which phonons in the heterostructure provide the momentum necessary to link the Fermi surfaces. Pronounced peaks in the second derivative of the tunnel current, d2I/dV2, are observed at voltages where known phonon modes in the tunnel junction have a high density of states. In addition, features in the tunneling conductance attributed to single electron charging of nanometer-scale defects in the boron nitride are also observed in these devices. The small electronic density of states of graphene allows the charging spectra of these defect states to be electrostatically tuned, leading to "Coulomb diamonds" in the tunneling conductance. [ABSTRACT FROM AUTHOR]

The objectives of this study were to determine (i) whether Chlamydia abortus would adhere to or penetrate the intact zona pellucida (ZP-intact) of early in vivo -derived caprine embryos, after in vitro infection; and (ii) the efficacy of the International Embryo Transfer Society (IETS) washing protocol for bovine embryos. Fifty-two ZP-intact embryos (8–16 cells), obtained from 14 donors were used in this experiment. The embryos were randomly divided into 12 batches. Nine batches (ZP-intact) of five embryos were incubated in a medium containing 4 × 10 7 Chlamydia /mL of AB7 strain. After incubation for 18 hours at 37 °C in an atmosphere of 5% CO 2 , the embryos were washed in batches in 10 successive baths of a phosphate buffer saline and 5% fetal calf serum solution in accordance with IETS guidelines. In parallel, three batches of ZP-intact embryos were used as controls by being subjected to similar procedures but without exposure to C. abortus . The 10 wash baths were collected separately and centrifuged for 1 hour at 13,000 × g. The washed embryos and the pellets of the 10 centrifuged wash baths were frozen at −20 °C before examination for evidence of C. abortus using polymerase chain reaction. C. abortus DNA was found in all of the infected batches of ZP-intact embryos (9/9) after 10 successive washes. It was also detected in the 10th wash fluid for seven batches of embryos, whereas for the two other batches, the last positive wash bath was the eighth and the ninth, respectively. In contrast, none of the embryos or their washing fluids in the control batches were DNA positive. These results report that C. abortus adheres to and/or penetrates the ZP of in vivo caprine embryos after in vitro infection, and that the standard washing protocol recommended by the IETS for bovine embryos, failed to remove it. The persistence of these bacteria after washing makes the embryo a potential means of transmission of the bacterium during embryo transfer from infected donor goats to healthy recipients and/or their offspring. Nevertheless, the detection of C. abortus DNA by polymerase chain reaction does not prove that the bacteria found was infectious. Further studies are required to investigate whether enzymatic and/or antibiotic treatment of caprine embryos infected by C. abortus would eliminate the bacteria from the ZP. [ABSTRACT FROM AUTHOR]

The surface-enhanced Raman scattering (SERS) spectroscopy and inelastic electron tunneling spectroscopy (IETS) are employed to study trans-1,2-bis (4-pyridyl) ethylene (BPE)/gold system. Both junction and complex forms are considered for the SERS simulations. It is predicted that the peak at 1581 cm - 1 is more intense in the junction forms than that in the complex forms. Time dependent density functional theory calculations show that the relative intensity is mainly controlled by the excitation energy derivative respect to the normal modes, and the total intensity is governed by the excitation energy of the excited states. The C H bending modes dominate the IET spectra when BPE adsorbed on the flat gold surfaces. While, the pyridyl ring deformation modes are more active when BPE adsorbed on the edge of the gold clusters. For BPE adsorbed on the tip of gold clusters, the pyridyl ring and C C stretching modes show significant contribution to the IET spectra. [ABSTRACT FROM AUTHOR]

Abstract: The detection of significant bacterial loads of Coxiella burnetii in flushing media and tissue samples from the genital tracts of nonpregnant goats represents a risk factor for in utero infection and transmission during embryo transfer. The aim of this study was to investigate (1) whether cells of early goat embryos isolated from in vivo–fertilized goats interact with C. burnetii in vitro, (2) whether the embryonic zona pellucida (ZP) protects early embryo cells from infection, and (3) the efficacy of the International Embryo Transfer Society (IETS) washing protocol for bovine embryos. The study was performed in triple replicate: 12 donor goats, certified negative by ELISA and polymerase chain reaction, were synchronized, superovulated, and subsequently inseminated by Q fever-negative males. Sixty-eight embryos were collected 4 days later by laparotomy. Two-thirds of the resulting ZP-intact and ZP-free 8- to 16-cell embryos (9-9, 11-11, and 4-4 in replicates 1, 2, and 3, respectively) were placed in 1 mL minimum essential medium containing 109 C. burnetii CBC1 (IASP, INRA Tours). After overnight incubation at 37 °C and 5% CO2, the embryos were washed according to the IETS procedure. In parallel, the remaining third ZP-intact and ZP-free uninfected embryos (3-3, 5-5, and 2-2 in replicates 1, 2, and 3, respectively) were subjected to the same procedures, but without C. burnetii, thus serving as controls. The 10 washing fluids for all batches of each replicate were collected and centrifuged for 1 hour at 13,000 × g. The washed embryos and pellets were tested by polymerase chain reaction. Coxiella burnetii DNA was found in all batches of ZP-intact and ZP-free infected embryos after 10 successive washes. It was also detected in the first five washing fluids for ZP-intact embryos and in the first eight washing fluids for ZP-free embryos. None of the control batches (embryos and washing fluids) were found to contain bacterial DNA. These results clearly indicate that caprine early embryonic cells are susceptible to infection by C. burnetii. The bacterium shows a strong tendency to adhere to the ZP after in vitro infection, and the washing procedure recommended by the IETS for bovine embryos failed to remove it. The persistence of these bacteria makes the embryo a potential means of transmission to recipient goats. Further studies are needed to investigate whether the enzymatic treatment of caprine embryos infected by C. burnetii would eliminate the bacteria from the ZP. [Copyright &y& Elsevier]

Abstract: The advent of milli-kelvin scanning tunneling microscopes (STM) with inbuilt magnetic fields has opened access to the study of magnetic phenomena with atomic resolution at surfaces. In the case of single atoms adsorbed on a surface, the existence of different magnetic energy levels localized on the adsorbate is due to the breaking of the rotational invariance of the adsorbate spin by the interaction with its environment, leading to energy terms in the meV range. These structures were revealed by STM experiments in IBM Almaden in the early 2000s for atomic adsorbates on CuN surfaces. The experiments consisted in the study of the changes in conductance caused by inelastic tunneling of electrons (IETS, inelastic electron tunneling spectroscopy). Manganese and Iron adatoms were shown to have different magnetic anisotropies induced by the substrate. More experiments by other groups followed up, showing that magnetic excitations could be detected in a variety of systems: e.g. complex organic molecules showed that their magnetic anisotropy was dependent on the molecular environment, piles of magnetic molecules showed that they interact via intermolecular exchange interaction, spin waves were excited on ferromagnetic surfaces and in Mn chains, and magnetic impurities have been analyzed on semiconductors. These experiments brought up some intriguing questions: the efficiency of magnetic excitations was very high, the excitations could or could not involve spin flip of the exciting electron and singular-like behavior was sometimes found at the excitation thresholds. These facts called for extended theoretical analysis; perturbation theories, sudden-approximation approaches and a strong coupling scheme successfully explained most of the magnetic inelastic processes. In addition, many-body approaches were also used to decipher the interplay between inelastic processes and the Kondo effect. Spin torque transfer has been shown to be effective in changing spin orientations of an adsorbate in theoretical works, and soon after it was shown experimentally. More recently, the previously mentioned strong coupling approach was extended to treat the excitation of spin waves in atomic chains and the ubiquitous role of electron–hole pair creation in de-exciting spins on surfaces has been analyzed. This review article expounds these works, presenting the theoretical approach by the authors while trying to thoroughly review parallel theoretical and experimental works. [Copyright &y& Elsevier]

Given an IET T : [0, 1) → [0, 1) and decreasing sequence of positive real numbers with divergent sum $${{\bf a} = \{a_i\}^\infty_{i=1}}$$ we consider where B( x, r) is the ball of radius r about x. We prove that We prove related results for geodesic flows on translation surfaces and stronger results which treat the measure of every horizontal and vertical line of S ( a). [ABSTRACT FROM AUTHOR]

Abstract: Unimolecular or molecular-scale electronics has made huge progress towards unimolecular resistors, switches, rectifiers, negative differential resistance devices, and gain-less single-electron transistors. Twelve unimolecular rectifiers have been found in Tuscaloosa, and many others elsewhere. The challenges are to understand the “metal|molecule” interface and to make reliable unimolecular electronic devices. [Copyright &y& Elsevier]

Abstract: This paper reviews the following electrical characterization techniques for measuring the microscopic bonding structures, impurities, and electrically active defects in advanced CMOS gate stacks: (1) inelastic electron tunneling spectroscopy (IETS), (2) lateral profiling of threshold voltages, interface-trap density, and oxide charge density distributions along the channel of a MOSFET, and (3) pulse agitated substrate hot electron injection (PASHEI) technique for measuring trapping effects in the gate dielectric at low and modest gate voltages. [Copyright &y& Elsevier]

This paper reviews the following electrical characterization techniques for measuring the microscopic bonding structures, impurities, and electrically active defects in advanced CMOS gate stacks: 1) inelastic electron tunneling spectroscopy (IETS), 2) lateral profiling of threshold voltages, interface-trap density, and oxide charge density distributions along the channel of an MOSFET, and 3) pulse agitated substrate hot electron injection (PASHEI) technique for measuring trapping effects in the gate dielectric at low and modest gate voltages. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to demonstrate that embryo transfer can be used to produce CAEV-free kids from CAEV-infected biological mothers when appropriate procedure is implemented. Twenty-eight goats that had tested positive for CAEV using PCR on vaginal secretions were used as embryo donors. Embryos with intact-ZP were selected and washed 10 times; they were then frozen and used for transfer into CAEV-free recipient goats. Nineteen of the 49 recipient goats gave birth, producing a total of 23 kids. Three blood samples were taken from each recipient goat, 10 days before, during, and 10 days after parturition; these were tested for CAEV antibodies using ELISA and for CAEV proviral DNA using PCR. The mothers were then euthanized. Tissue samples were taken from the lungs, udder, and retromammary and prescapular lymph nodes. The kids were separated from their mothers at birth. Seven of them died. At 4 months of age, 16 kids were subjected to drug-induced immunosuppression. Blood samples were taken every month from birth to 4 months of age; samples were then taken on days 15, 21, and 28 after the start of the immunosuppressive treatment. The kids were then euthanized and tissue samples taken from the carpal synovial membrane, lung tissue, prescapular lymph nodes, inguinal and retromammary lymph nodes, and uterus. All samples from the 19 recipient goats and 23 kids were found to be negative for CAEV antibodies and/or CAEV proviral DNA. Under acute conditions for infection this study clearly demonstrates that embryo transfer can be safely used to produce CAEV-free neonates from infected CAEV donors. [Copyright &y& Elsevier]

Abstract: Recent studies of molecules on surface by the use of tunneling electrons of scanning tunneling microscopy (STM) are reviewed. Characteristic features of tunneling current of STM are used not only for real space imaging with an atomic resolution but also are utilized for chemical analysis of a single molecule and manipulation of a molecule with controlled excitation of their vibration modes. As promising candidates of chemical analysis at a single molecule level, inelastic tunneling spectroscopy (IETS) researches are discussed. The mechanism of vibration excitation in STM-IETS is compared with that in high-resolution electron energy loss spectroscopy (HR-EELS). Successful observations of vibration modes of molecules such as C–H stretching mode are introduced. At the same time, expected increase of the importance of resonant scattering mechanism in STM-IETS compared with the conventional IETS is examined, whose mechanism assumes the trapping of tunneling electrons in the adsorbate resonant state and the formation of temporary negative ions. Next, applications of tunneling electrons to the manipulations of adsorbates are discussed focusing on the phenomena induced by vibrational excitations. STM has a unique character of high current density, which cannot be obtained with conventional sources. The similarity between the vibration excitation with the high current of STM and the phenomenon known as desorption induced by multielectron transfer (DIMET) are discussed. Surface phenomena such as desorption, hopping, rotation and chemical reactions are excited as a consequence of sequential climbing of ladders of a vibrational mode formed in the potential well. The intrinsic high current of STM tunneling current enables such multiple excitations in a more controllable manner than the use of photogenerated hot electrons, and is expected to make a contribution to the understanding of elemental processes of surface phenomena. [Copyright &y& Elsevier]

The International Embryo Transfer Society (IETS) was founded in 1974. Early members used the society as a forum for the exchange of scientific and technical information relevant to a newly emerging embryo transfer industry. The impact that embryo transfer could have on the international trade of livestock genetics was clear by 1982, so the IETS commissioned the Import/Export Committee. The initial challenge for this Committee was to deal with concerns about disease transmission via embryo transfer. Many of the early concerns have been dispelled, but at the time they threatened the continued development of a fledgling industry. Over the past two decades, many new critical challenges have been met and managed by this Committee, which was recently renamed the Health and Safety Advisory Committee (HASAC). Assessing risks of animal disease transmission via reproductive technologies and establishing protocols for managing these risks are still major issues for HASAC. However, additional concerns have developed as views of the society changed and as novel applications of biotechnology in farm animals were identified. This paper is intended to chronicle some of the major changes and challenges that were managed by members of the HASAC and its Subcommittees from the early years of embryo transfer to the current millennium with technological advances in molecular biology. [Copyright &y& Elsevier]

• Rise in inelastic transmission on changing the molecule-electrode coupling strength. • Relative displacements of the encapsulated metal also plays very prominent role. • In the present study electrode-molecule separation has been varied from 1.6 to 2.2 Å. • Inelastic transmission in strong coupling case is 100 times of weak coupling case. • It is also notable that in stronger coupling regime phonon mode numbered 5 contributes to current in μA range and relevant excitation takes place at much lower energy which is obviously in complete contrast with weakly coupled system; where higher energy phonon modes numbered 50–56 have chance to contribute current in μA range. Hence, in respect of low energy inelastic transmission strongly coupled system is preferable. • Larger packing of in-phase tunneling electron within strongly coupled Hf@C 28. Herein, we report how tuning of molecule-electrode coupling strength can turn on the coupling of tunnelling electrons with vibrational modes of central molecule in the two-probe configuration of Hf@C28 self-assembled between two Au(1 1 1) electrodes and thereby activating inelastic transmission path. The in silico study compares quantum transport properties of optimized configuration having C-Au bond length of 2.01 Å (weakly-bound), with strongly-bound configuration having C-Au bond length of 1.6 Å. It is observed that in weak-coupling the inelastic transmission coefficient is insignificant, however with strong-coupling symmetric and asymmetric part of inelastic transmission together contributes to rise in inelastic current. This rise in inelastic current is attributed to the resonance of phononic vibration corresponding to low-energy phonon-mode and energy of tunnelling electron close to applied bias 0.15–0.25 V. Observed results have been substantiated through an analysis of high density in-phase transmission pathways within the molecular part mediated by resonating electrons and phonon modes. [ABSTRACT FROM AUTHOR]

• Metal-string molecular junctions (MSMJs) tend to influence primarily stretching, bending, rocking and scissoring modes. • Quantum interference effect is manifested in certain MSMJs for which the energy gap lies within optical phonon energies. • Phonon-mediated Fano resonances in MSMJs may lead to the suppression of higher wavenumber vibrational modes. • Single molecular shot noise may exhibit nearly Poissonian behavior due to phonon-assisted quantum tunneling of electrons. • Charge transport in MSMJs can be controlled by selective design of metal centers as well as electrode orientations. It is often intriguing experimentally to take stock of how conformational changes in the device configuration may impact the overall charge transport behavior of single-molecule junctions. Based on the allied approach of density functional theory and non-equilibrium Green's function formalism, we explore here the effect of junction heterogeneity on inelastic charge transport in various metal-string based single-molecule devices. The constituent active elements being sensitive to the resonant levels, transition metal centers are found to influence stretching, bending, and torsional excitation modes, while rocking and scissoring modes are controlled largely by the axial ligands. For certain molecular conformations and electrode orientations, phonon-assisted quantum interference effect may crop up, leading to the suppression of higher wavenumber vibrational modes. The resulting inelastic spectra are likely to take the shape of dominant Fano resonance or anti-resonance, depending on whether phonons are emitted or absorbed. Such nanoscale quantum interference effect is manifested especially in those metal-string molecular junctions for which the energy gap (between localized and delocalized virtual states) lies well within the optical phonon energies (Δ E | H O M O - L U M O | < 40 meV). It also turns out that single molecular shot noise can exhibit nearly Poissonian behavior if the inter-channel tunneling through frontier orbitals is accompanied by phonon absorption or emission following a slow relaxation process. Charge transport properties across metal-string complexes can thus potentially be tuned by selective architecture of the metal centers and also, by preferred orientation of nanoscale electrodes in a bid to build up molecular devices with desirable controllability. [ABSTRACT FROM AUTHOR]

A detailed computational analysis has been performed, considering copper atomic contacts that are exposed directly to water molecules, hydroxyl groups, and monatomic as well as molecular hydrogen and oxygen species. The optimized physical bonding structure, electrical conductance and inelastic tunneling spectra (IETS) have been determined theoretically for moderately large structures by performing appropriate ab initio and semi-empirical calculations. By considering the aforementioned properties, it has been possible to determine that some of the molecular bridging structures may be regarded as being highly-probable outcomes, resulting from the exposure of copper electrodes to the atomic/molecular contaminants. We specifically identify the conductance properties of a variety of configurations including examples with very high and very low conductance values. This is done in order to identify junction geometries that may be realized experimentally and their conductance and IETS signatures. By reporting geometries with very high and very low conductance values here, we intend to provide a wider perspective view than previous studies of copper-molecular junctions that have focused on high conductance structures. In addition, we explore the properties of metal junctions with multiple molecules, a class of systems for which little theoretical work has been available in the molecular electronics literature. We find that water molecules surrounding the junction can influence the bonding geometry of the molecules within the junction and consequently can affect strongly the calculated conductances of such junctions., (© 2020 IOP Publishing Ltd.)