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The point at which the experience of grief in response to bereavement becomes 'pathological' has been debated for many years without resolution. This article reviews the current status of this debate. The debate centers around the extent to which 'complicated grief' represents a truly unique pathological entity, when contrasted with major depressive disorder, posttraumatic stress disorder, and 'uncomplicated grief.' Significant research findings suggest it may be possible to distinguish grief from depressed as well as traumatic forms of distress, with acceptable reliability and validity. Yet, 'complicated grief' relates to both of these types of distress as well as to a unique aspect--separation distress. It is at the intersection of these types of distress with significant disruption of daily life functioning that we find the proposed diagnosis of 'complicated grief.' The question is whether this diagnosis should be designated at this time, and, if so, how. This article concludes in favor of a compromise position that the diagnosis should be incorporated into DSM-V but relegated to its Appendix B [disorders proposed for further study] due to the lack of clarity surrounding its diagnostic criteria. [ABSTRACT FROM AUTHOR]

Objective: This study examines whether stressful negative life events and pessimism were associated with lower natural killer cell cytotoxicity (NKCC) and T cytotoxic/suppressor cell (CD8+CD3+) percentage in black women co-infected with human immunodeficiency virus Type 1 (HIV-1) and human papillomavirus (HPV), a viral initiator of cervical cancer.Method: Psychosocial interviews, immunological evaluations, and cervical swabs for HPV detection and subtyping were conducted on 36 HIV+ African-American, Haitian, and Caribbean women.Results: Greater pessimism was related to lower NKCC and cytotoxic/suppressor cells after controlling for presence/absence of HPV Types 16 or 18, behavioral/lifestyle factors, and subjective impact of negative life events.Conclusions: A pessimistic attitude may be associated with immune decrements, and possibly poorer control over HPV infection and increased risk for future promotion of cervical dysplasia to invasive cervical cancer in HIV+ minority women co-infected with HPV. [ABSTRACT FROM AUTHOR]

Extensive efforts have been dedicated towards designing new organic materials that display solid-state fluorescence and possess optical activity, thereby leading to the fabrication of materials emitting circularly polarized light. Existing organic materials usually suffer from two limitations, a low dissymmetry factor ( g lum ) and weak or no fluorescence in the solid state. Herein, we have demonstrated a naphthalene imide-based dyad system that remains fluorescent even in powder form and displays circularly polarized luminescence in its aggregated and solid state with significantly high g lum values.

Fluorescent materials find numerous applications in light-based devices, but their utilization is severely affected by concentration caused quenching of fluorescence, the extreme form of which is the total loss of fluorescence in the solid state. Introduction of bulky substituents remains the most frequently applied fluorescence revival strategy, but requires multi-step synthetic modifications. We have demonstrated a simple one step supramolecular gel-based strategy to preserve the fluorescence in the solid state.

Mono- and bis-salen functionalised [2]rotaxanes have been synthesised from the esterification of [2]rotaxanes containing phenol-terminated threads (salen = N,N'-bis(salicylidene)ethylenediamine). The [2]rotaxanes have general formula [RH][Cr7NiF8(O2CtBu)16], where [RH]+ is a thread with a central secondary ammonium site that templates a [Cr7NiF8(O2CtBu)16]- ring. The threads are terminated at one or both ends by carboxylic acid functionalised salen groups. The {M(salen)} groups can be free-base [M = (H+)2] or metallated [M = Cu2+, Ni2+, (VO)2+]. The [2]rotaxanes have been characterised by single crystal XRD and solid- and solution-state EPR spectroscopy. Where two paramagnetic M ions are involved [M = Cu2+ and/or (VO)2+] the [2]rotaxanes contain three electron spin S = ½ centres, since the {Cr7Ni} ring has an S = ½ ground state which is well isolated at low temperatures. These three-spin [2]rotaxanes have been characterised in solution by pulsed dipolar EPR spectroscopies (DEER, also known as PELDOR, and RIDME). The M···M and M···{Cr7Ni} interactions measured are consistent with dipolar interactions and also with the distances from single crystal XRD., (© 2024 Wiley‐VCH GmbH.)

A synthetic strategy is demonstrated to prepare two distinct trimers of antiferromagnetically coupled {Cr 7 Ni} rings, substantially varying the magnetic interactions between the spin centres. The interactions were studied using multi-frequency cw EPR: in a trimer linked via non-covalent H-bonding interactions no measurable interaction between rings was seen, while in a trimer linked via iso-nicotinate groups isotropic and anisotropic exchange interactions of +0.42 and -0.8 GHz, respectively, were observed. The latter are the same as those for a simpler hetero-dimer system, showing how the spin-spin interactions can be built in a predictable and modular manner in these systems., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

For the molecular properties in which energy transfer/migration is determinantal, such as triplet-triplet annihilation-based photon up-conversion (TTAUC), the overall performance is largely affected by the intermolecular distance and relative molecular orientations. In such scenarios, tools that may steer the intermolecular interactions and provide control over molecular organisation in the bulk, become most valuable. Often these non-covalent interactions, found predominantly in supramolecular assemblies, enable pre-programming of the molecular network in the assembled structures. In other words, by employing supramolecular chemistry principles, an arrangement where molecular units are arranged in a desired fashion, very much like a Lego toy, could be achieved. This leads to enhanced energy transfer from one molecule to other. In recent past, chiral luminescent systems have attracted huge attention for producing circularly polarized luminescence (CPL). In such systems, chirality is a necessary requirement. Chirality induction/transfer through supramolecular interactions has been known for a long time. It was realized recently that it may help in the generation and amplification of CPL signals as well. In this review article we have discussed the applicability of self-/co-assembly processes for achieving maximum TTA-UC and CPL in various molecular systems.

Here we report the synthesis and structural characterization of four [7]rotaxanes formed by coordinating hybrid inorganic-organic [2]rotaxanes to a central {Ni 12 } core. X-ray single crystal diffraction demonstrate that [7]rotaxanes are formed, with a range of conformations in the crystal. Small angle X-ray scattering supported by molecular dynamic simulations demonstrates that the large molecules are stable in solution and also show that the conformers present in solution are not those found in the crystal. Pulsed EPR spectroscopy show that phase memory times for the {Cr 7 Ni} rings, which have been proposed as qubits, are reduced but not dramatically by the presence of the {Ni 12 } cage., Competing Interests: The authors declare no competing financial interest., (This journal is © the Partner Organisations.)

Organic molecules with an active dipole moment have a natural propensity to align in an antiparallel fashion in the solid state, resulting in zero macroscopic polarization. This primary limitation makes the material unresponsive to switching with electric fields, mechanical forces, and to intense laser light. A single-component organic material that bestows macroscopic dipole-driven electro-mechanical and optical functions, e.g. , piezoelectric, ferroelectric and nonlinear optical (NLO) activity, is unprecedented due to the design challenges imparted by crystal symmetry and dipole orientations. Herein we report a crystalline organic material that self-assembles with a polar order ( P 1 ), and is endowed with a high piezoelectric coefficient ( d 33 -47 pm V -1 ), as well as ferroelectric and Debye-type relaxor properties. In addition, it shows second harmonic generation (SHG) activity, which is more than five times that of the benchmark potassium dihydrogen phosphate. Piezoelectric force microscopy (PFM) images validated electro-mechanical deformations. Piezoresponse force spectroscopy (PFS) studies confirmed a signature butterfly-like amplitude and a phase loop. To the best of our knowledge, this is the first report of a folded supramolecular π-system that manifests unidirectionally oriented dipoles and exhibits piezoelectricity, ferroelectricity, and has excellent ability to generate second harmonic light. These findings can herald new design possibilities based on folded architectures to explore opto-, electro- and mechano-responsive multifaceted functions., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Dipolar coupled multi-spin systems have the potential to be used as molecular qubits. Herein we report the synthesis of a molecular multi-qubit model system with three individually addressable, weakly interacting, spin 1 / 2 ${{ 1/2 }}$ centres of differing g-values. We use pulsed Electron Paramagnetic Resonance (EPR) techniques to characterise and separately address the individual electron spin qubits; Cu II , Cr 7 Ni ring and a nitroxide, to determine the strength of the inter-qubit dipolar interaction. Orientation selective Relaxation-Induced Dipolar Modulation Enhancement (os-RIDME) detecting across the Cu II spectrum revealed a strongly correlated Cu II -Cr 7 Ni ring relationship; detecting on the nitroxide resonance measured both the nitroxide and Cu II or nitroxide and Cr 7 Ni ring correlations, with switchability of the interaction based on differing relaxation dynamics, indicating a handle for implementing EPR-based quantum information processing (QIP) algorithms., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Polymer beads have been used as the core of magnetic particles for around twenty years. Here we report studies to attach polymetallic complexes to polymer beads for the first time, producing beads of around 115 microns diameter that are attached to 10 14 hybrid inorganic-organic [2]rotaxanes. The bead is then formally a [10 14 ] rotaxane. The number of complexes attached is counted by EPR spectroscopy after including TEMPO radicals within the thread of the hybrid [2]rotaxanes., (© 2022. The Author(s).)

Gold(i) bridged dimeric and trimeric structures of a ground state spin S = 1/2 heterometallic {Cr 7 Ni} wheel have been prepared and studied by continuous wave (CW) and pulsed wave EPR spectrometry. The {Cr 7 Ni} relaxation time constants (T 1 and T m ) show rates matching well with previous observations. Four pulse Double Electron Resonance (DEER) studies suggest presence of more than one conformations. Small Angle X-ray Scattering (SAXS) in conjunction with Molecular Dynamic (MD) Simulations were performed to look at the possible conformations in solution. In line with DEER results, simulation data further indicated more flexible molecular geometry in solution than the one in solid state.

Molecules that are the size of small proteins are difficult to make. The most frequently examined route is via self-assembly, and one particular approach involves molecular nanocapsules, where ligands are designed that will enforce the formation of specific polyhedra of metals within the core of the structure. Here we show that this approach can be combined with mechanically interlocking molecules to produce nanocapsules that are decorated on their exterior. This could be a general route to very large molecules, and is exemplified here by the synthesis and structural characterization of a [13]rotaxane, containing 150 metal centres. Small angle X-ray scattering combined with atomistic molecular dynamics simulations demonstrate the compound is intact in solution.

Here we show that a structure containing a polymeric interlocking daisy chain is obtained from the reaction of an inorganic-organic [2]rotaxane [HB{CrIII7NiII(μ-F)8(O2CtBu)16}], where B is an organic thread terminated with a bi-pyridyl unit, with an oxo-centered metal carboxylate triangle [FeIII2CoII(μ3-O)(O2CtBu)6(HO2CtBu)3].

Three classes of donor-acceptor (D-A) π-extended chromophores (1-12) were synthesized through a phosphite-mediated cross-coupling reaction, in which the anhydride- or imide-based π-As and number of tetrathiafulvalene (TTF)/dithiafulvalene (DTF) Ds were systematically changed. Large π rings, such as benzoperylene and coronene, were integrated into the TTF/DTF unit, for the first time, to overcome their high insolubility. The anhydride and imide groups in the π acceptors can significantly alter the frontier orbitals and influence the optoelectronic properties. The D moieties allow the formation of radical cations (D .+ ) and the π-extended A moieties aid the formation of radical anions (A .- ) by oxidation/reduction under ambient conditions. The molecules revealed UV/Vis/near-IR absorption, fluorescence extending into the near-IR region, and amphoteric electrochemical properties. Chromophores 10 and 12 show solvatochromism in a wide range of solvents. The π-As with anhydride functionality allow easier electron uptake, relative to the imide groups, whereas the increasing number of D TTF/DTF units make them easy to oxidize. Interestingly, the trans-TTF-fused molecules (1, 6, and 11) exhibited a mixed-valence state in the mid-IR region (ν˜ =5130-4000 cm -1 ). Moderate electron coupling between the redox centers is inferred to the compounds being of Robin-Day class II. The multistate redox activity along with panchromism and near-/mid-IR optical absorption of these systems can be attractive towards advanced switchable materials., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: To assess whether a spot urinary albumin:creatinine ratio (ACR) measured before 20 weeks of gestation can predict subsequent development of preeclampsia., Methods: The ACR was determined from midstream urine sample taken between 17 and 20 weeks of gestation. Urine albumin was measured by immunoturbidimetric method using commercially available kit (Beckman Coulter) through Beckman AU 480 fully automated biochemistry analyzer. Urine creatinine was measured by modified kinetic Jaffe reaction without deproteinization.[Formula: see text]Participants were then followed until delivery. Primary outcome measure was preeclampsia, secondary outcome measures were gestational hypertension, gestational diabetes mellitus, IUGR, and normal range estimate of urinary albumin-to-creatinine ratio was established., Result: The median spot urinary albumin-to-creatinine ratio measured between 17 and 20 weeks of gestation was 5.2 mg/g of creatinine (2.5-9.6). Women who subsequently developed preeclampsia had higher spot urinary albumin-to-creatinine ratio (median 30.795 [9.7-92.8]) in comparison with women who developed gestational hypertension (median 5.2 [0.7-7.2]) and unaffected women (median 5.2 [2.5-9.6]). The urinary albumin-to-creatinine ratio of the mother who developed IUGR was significantly higher. By ROC analysis, the optimum ACR to predict preeclampsia was 9.85 mg/g of creatinine. The relative risk of developing preeclampsia in women with urinary albumin-to-creatinine ratio more than 9.85 mg/g of creatinine was higher than in the women who had urinary albumin-to-creatinine ratio less than 9.85 mg/g of creatinine., Conclusion: A spot urinary albumin-to-creatinine ratio of more than 9.8 mg/g of creatinine can predict the development of preeclampsia in later pregnancy with the sensitivity and specificity of 67 and 76%, respectively. However, additional studies and cost-benefit analysis are required to confirm these finding before recommending this test for screening purposes.

Aggregation-induced photon upconversion (iPUC) based on a triplet-triplet annihilation (TTA) process is successfully developed via controlled self-assembly of donor-acceptor pairs in organogel nanoassemblies. Although segregation of donor from acceptor assemblies has been an outstanding problem in TTA-based UC and iPUC, we resolved this issue by modifying both the triplet donor and aggregation induced emission (AIE)-type acceptor with glutamate-based self-assembling moieties. These donors and acceptors co-assemble to form organogels without segregation. Interestingly, these donor-acceptor binary gels show upconversion at room temperature but the upconversion phenomena were lost upon dissolution of the gels on heating. The observed changes in TTA-UC emission were thermally reversible, reflecting the controlled assembly/disassembly of the binary molecular systems. The observed on/off ratio of UC emission was much higher than that of the aggregation-induced fluorescence of the acceptor, which highlights the important role of iPUC, i.e., multi-exciton TTA for photoluminescence switching. This work bridges iPUC and supramolecular chemistry and provides a new strategy for designing stimuli-responsive upconversion systems.