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We apply the extended local hidden gauge formalism to study the meson-meson interactions with the quark constituents $cc\bar c\bar c$, $cc\bar c\bar b/\bar c\bar c cb$, $cc\bar b\bar b/\bar c\bar c bb$, $bb\bar c\bar b/\bar b\bar b cb$, and $bb\bar b\bar b$, where the exchanged mesons are the fully-heavy vector mesons $J/\psi$, $B_c^*$, and $\Upsilon$. We solve the coupled-channel Bethe-Salpeter equation to derive two poles in the $bb\bar{c}\bar{b}$ system and two poles in the $cc\bar{c}\bar{b}$ system. There are also four charge-conjugated poles in the $\bar{b}\bar{b}cb$ and $\bar{c}\bar{c}cb$ systems. In the $bb\bar{c}\bar{b}$ system, one pole corresponds to a sub-threshold bound state when the cutoff momentum is set to $\Lambda > 850$ MeV. The other pole in this system corresponds to a sub-threshold bound state when $\Lambda > 1100$ MeV. In the $cc\bar{c}\bar{b}$ system, the two poles correspond to sub-threshold bound states only when $\Lambda > 1550$ MeV and $\Lambda > 2650$ MeV. This makes them difficult to identify as deeply-bound hadronic molecules. We propose investigating the two poles of the $bb\bar{c}\bar{b}$ system in the $ \mu^+\mu^-B_c^-$channel at the LHC., Comment: 9 pages, 2 figures, 2 tables, revised version

A lot of exotic hadrons were reported in the past twenty years, which bring us the renaissance of the hadron spectroscopy. Most of them can be understood as hadronic molecules, whose interactions are mainly due to the exchange of light mesons, and specifically, light vector mesons through the coupled-channel unitary approach within the local hidden-gauge formalism. It is still controversial whether the interaction arising from the exchange of heavy mesons is capable of forming hadronic molecules. We apply the coupled-channel unitary approach to study the fully-heavy $b \bar b c \bar c$ system, where the exchanged mesons can only be the fully-heavy vector mesons $J/\psi$, $B_c^*$, and $\Upsilon$. Especially, the $J/\psi$ meson is much lighter than the $B_c^{(*)}$ mesons, so the present study can be taken as a general investigation on the question whether a lower-mass fully-heavy meson is able to bind two higher-mass fully-heavy hadrons. Our results suggest the existence of the fully-heavy hadronic molecules $|B_c^{+} B_c^{-}; J^{PC}=0^{++} \rangle$, $|B_c^{*+} B_c^{-} - c.c.; J^{PC}=1^{+-} \rangle$, and $|B_c^{*+} B_c^{*-}; J^{PC}=2^{++} \rangle$ as well as the possible existence of $|B_c^{*+} B_c^{-} + c.c.; J^{PC}=1^{++} \rangle$. These states are potentially to be observed in the $\mu^+ \mu^- J/\psi$ and $\mu^+ \mu^- \Upsilon$ channels in future ATLAS, CMS, and LHCb experiments., Comment: 8 pages, 6 figures, 3 tables, slightly revised

We study the possibly-existing molecular pentaquark states with open charm and bottom flavors, {\it i.e.}, the states with the quark contents $c\bar{b}qqq$ and $b\bar{c}qqq$ ($q=u,d,s$). We investigate the meson-baryon interactions through the coupled-channel unitary approach within the local hidden-gauge formalism, and extract the poles by solving the Bethe-Salpeter equation in coupled channels. These poles qualify as molecular pentaquark states, which are dynamically generated from the meson-baryon interactions through the exchange of vector mesons. Our results suggest the existence of the $\Sigma_c^{(*)} B^{(*)}$ and $\Sigma_b^{(*)} \bar{D}^{(*)}$ molecular states with isospin $I=1/2$, the $\Xi_c^{(\prime,*)} B^{(*)}$ and $\Xi_b^{(\prime,*)} \bar{D}^{(*)}$ molecular states with isospin $I=0$ and $I=1$, as well as the $\Omega_c^{(*)} B^{(*)}$ and $\Omega_b^{(*)} \bar D^{(*)}$ molecular states with isospin $I=1/2$., Comment: 25 pages, 6 figures, 7 tables, revised version to be published in EPJA

We study the hadronic molecular states with the quark content $bc\bar{s}\bar{q}$ by investigating the interactions of the $\bar{B}_s D$, $\bar{B} D_s$, $\bar{B}_s^* D$, $\bar{B}^* D_s$, $\bar{B}_s D^*$, $\bar{B} D_s^*$, $\bar{B}_s^* D^*$, and $\bar{B}^* D_s^*$ systems. By solving the Bethe-Salpeter equation within the extended local hidden gauge formalism, we find altogether six poles qualifying as possible hadronic molecular states: one pole of $J^P=0^+$ below the $\bar{B}_s D$-$\bar{B}D_s$ threshold, one pole of $J^P=1^+$ below the $\bar{B}_s^* D$-$\bar{B}^* D_s$ threshold, one pole of $J^P=1^+$ below the $\bar{B}_s D^*$-$\bar{B}D_s^*$ threshold, and three poles of $J^P=0^+/1^+/2^+$ below the $\bar{B}_s^* D^*$-$\bar{B}^* D_s^*$ threshold. Their binding energies are calculated to be about 10-20 MeV with the cut-off momentum $q_\textrm{max}=600\textrm{ MeV}$. Similarly, we study the hadronic molecular states with $bs\bar{c}\bar{q}$ by investigating the interactions of the $\bar{B}\bar{D}_s$, $\bar{B}_c\bar{K}$, $\bar{B}^*\bar{D}_s$, $\bar{B}_c^*\bar{K}$, $\bar{B}\bar{D}_s^*$, $\bar{B}_c\bar{K}^*$, $\bar{B}^*\bar{D}_s^*$, $\bar{B}_c^*\bar{K}^*$ systems, and the states with $bq\bar{c}\bar{s}$ by investigating the interactions of the $\bar{B}_s\bar{D}$, $\bar{B}_cK$, $\bar{B}_s^*\bar{D}$, $\bar{B}_c^*K$, $\bar{B}_s\bar{D}^*$, $\bar{B}_cK^*$, $\bar{B}_s^*\bar{D}^*$, $\bar{B}_c^*K^*$ systems. However, no deeply-bound poles are found in these systems., Comment: 12 pages, 9 figures, revised version to be published in PRD

We study the decay of $\Lambda_b\to J/\psi\Lambda\phi$ by taking into account the intermediate resonances $X(4140)$, $X(4160)$, and $P_{cs}(4459)$. In addition to the peak of the $X(4140)$, we also find a bump structure around 4160 MeV followed by a cusp structure around $D^*_s\bar{D}^*_s$ threshold in the $J/\psi\phi$ invariant mass distribution of the $\Lambda_b\to J/\psi\Lambda\phi$ process, which can be associated to the $D^*_s\bar{D}^*_s$ molecular state $X(4160)$. We also show that this reaction can also be used to confirm the existence of the hidden-charm pentaquark $P_{cs}(4459)$ with strangeness. We predict an enhancement structure close to the threshold in the $D^*_s\bar{D}^*_s$ invariant mass distribution of the $\Lambda_b\to D^*_s\bar{D}^*_s\Lambda$ process, which is the reflection of the $X(4160)$ and should not be misidentified with a new resonance. We strongly suggest experimentalists to further measure these processes, which can be useful to clarify the nature of $X(4140)$ and $X(4160)$ resonances, and to confirm the existence of the $P_{cs}(4459)$., Comment: 8 pages, 10 figures

A study investigated the job placement success of Michigan State University students using the campus career services and placement office in obtaining a job. Data were drawn from office records and a survey of 445 graduates in 1991-92 who requested and were granted an on-campus employer interview. In that year, the 2,685 students (35 percent of graduates) requesting on-campus employer interviews averaged 14 interview requests per student. Engineering students had the highest request and interview rate. Second interviews or plant visits were afforded to 63 percent of students interviewing on-campus. Business students had the highest success rate at this stage. Of students interviewed on campus, 44 percent received a job offer, representing 14 percent of the graduating class. Business, engineering, and communication majors had the highest job offer rates. It took an average of four on-campus interviews to obtain a second interview or plant visit, and two plant visits/second interviews to obtain a job offer. Invited on-campus interviews reduced, by nearly half, the effort required to obtain a job offer. Students invited by companies to interview were more likely to be women and to have higher grade point averages than those not invited. Students who did not receive job offers through Career Services and Placement used two job search methods to find employment: mailing resumes to and contacting employers, and responding to newspaper classifieds. These methods were rated as "not very helpful" in finding employment opportunities. (Author/MSE)