Novel modification of infrahyoid myocutaneous flap for the reconstruction of oral cavity defects.

This study was intended to describe the technique used and the results obtained with the modification of the infrahyoid flap (IHF) for the reconstruction of oral tongue defects following resection for advanced squamous cell carcinoma (SCC). Patients with oral tongue defects following ablation for T2 to T4a SCC had reconstructions using a modified infrahyoid flap. Demographic data, tumour characteristics, and the complications were evaluated for each patient. We observed no complications regarding the healing process of the donor site or success of the flap in 49 (of 55) patients. None of the flaps had massive oedema or venous congestion in the postoperative period. Six patients experienced flap-related complications of which five had partial skin paddle necrosis, but eventually their flaps recovered and re-epithelialised without any further intervention. However, total flap necrosis was seen in one patient in whom a pectoralis major flap was used for the defect reconstruction following revision surgery. History of previous radiotherapy to the neck (p = 0.003), tumour stage (p = 0.017), and metastasis to cervical lymph nodes (p = 0.004) were associated with higher prevalence of partial or total flap necrosis. The modified infrahyoid flap is a reliable, quick, and simple procedure with a reasonable cost that makes it a valuable option for the reconstruction of the oropharynx and oral cavity with minimal donor site morbidity and good outcomes. It seems the modified IHF is a valid surgical procedure that may be considered in selected patients undergoing reconstruction of oncological oral tongue defects with fewer complications.

Spatially controlled nano-structuring of silicon with femtosecond vortex pulses.

Engineering material properties is key for development of smart materials and next generation nanodevices. This requires nanoscale spatial precision and control to fabricate structures/defects. Lithographic techniques are widely used for nanostructuring in which a geometric pattern on a mask is transferred to a resist by photons or charged particles and subsequently engraved on the substrate. However, direct mask-less fabrication has only been possible with electron and ion beams. That is because light has an inherent disadvantage; the diffraction limit makes it difficult to interact with matter on dimensions smaller than the wavelength of light. Here we demonstrate spatially controlled formation of nanocones on a silicon surface with a positional precision of 50 nm using femtosecond laser ablation comprising a superposition of optical vector vortex and Gaussian beams. Such control and precision opens new opportunities for nano-printing of materials using techniques such as laser-induced forward transfer and in general broadens the scope of laser processing of materials.

Anosmia as a prominent symptom of COVID-19 infection.

According to WHO recommendations, everyone must protect themselves against Coronavirus disease 2019 (COVID-19), which will also protect others. Due to the lack of current effective treatment and vaccine for COVID-19, screening, rapid diagnosis and isolation of the patients are essential (1, 2). Therefore, identifying the early symptoms of COVID-19 is of particular importance and is a health system priority. Early studies from COVID-19 outbreak in China have illustrated several non-specific signs and symptoms in infected patients, including fever, dry cough, dyspnea, myalgia, fatigue, lymphopenia, and radiographic evidence of pneumonia (3, 4). Recently, a probability of association between COVID-19 and altered olfactory function has been reported in South Korea, Iran, Italy, France, UK and the United States (5-8). However, to our knowledge, the definite association between COVID-19 and anosmia has not been published.

Vectorizing the spatial structure of high-harmonic radiation from gas.

Strong field laser physics has primarily been concerned with controlling beams in time while keeping their spatial profiles invariant. In the case of high harmonic generation, the harmonic beam is the result of the coherent superposition of atomic dipole emissions. Therefore, fundamental beams can be tailored in space, and their spatial characteristics will be imparted onto the harmonics. Here we produce high harmonics using a space-varying polarized fundamental laser beam, which we refer to as a vector beam. By exploiting the natural evolution of a vector beam as it propagates, we convert the fundamental beam into high harmonic radiation at its focus where the polarization is primarily linear. This evolution results in circularly polarized high harmonics in the far field. Such beams will be important for ultrafast probing of magnetic materials.

Ultrafast generation and control of an electron vortex beam via chiral plasmonic near fields.

Vortex-carrying matter waves, such as chiral electron beams, are of significant interest in both applied and fundamental science. Continuous-wave electron vortex beams are commonly prepared via passive phase masks imprinting a transverse phase modulation on the electron's wavefunction. Here, we show that femtosecond chiral plasmonic near fields enable the generation and dynamic control on the ultrafast timescale of an electron vortex beam. The vortex structure of the resulting electron wavepacket is probed in both real and reciprocal space using ultrafast transmission electron microscopy. This method offers a high degree of scalability to small length scales and a highly efficient manipulation of the electron vorticity with attosecond precision. Besides the direct implications in the investigation of nanoscale ultrafast processes in which chirality plays a major role, we further discuss the perspectives of using this technique to shape the wavefunction of charged composite particles, such as protons, and how it can be used to probe their internal structure.

Adaptive Compressive Tomography with No a priori Information.

Quantum state tomography is both a crucial component in the field of quantum information and computation and a formidable task that requires an incogitable number of measurement configurations as the system dimension grows. We propose and experimentally carry out an intuitive adaptive compressive tomography scheme, inspired by the traditional compressed-sensing protocol in signal recovery, that tremendously reduces the number of configurations needed to uniquely reconstruct any given quantum state without any additional a priori assumption whatsoever (such as rank information, purity, etc.) about the state, apart from its dimension.

Efficient optical trapping with cylindrical vector beams.

Radially and azimuthally polarized beams can create needle-like electric and magnetic fields under tight focusing conditions, respectively, and thus have been highly recommended for optical manipulation. There have been reports on the superiority of these beams over the conventional Gaussian beam for providing a larger optical force in single beam optical trap. However, serious discrepancies in their experimental results prevent one from concluding this superiority. Here, we theoretically and experimentally study the impact of different parameters - such as spherical aberration, the numerical aperture of the focusing lens, and the particles' size - on optical trapping stiffness of radially, azimuthally, and linearly polarized beams. The result of calculations based on generalized Lorenz-Mie theory, which is in good agreement with the experiment, reveals that the studied parameters determine which polarization state has the superiority for optical trapping. Our findings play a crucial role in the development of optical tweezers setups and, in particular, in biophysical applications when laser-induced heating in the optical tweezers applications is the main concern.

Mapping complex polarization states of light on a solid.

Polarization states of light, represented by different points on a Poincaré sphere, can be readily analyzed for a Gaussian beam by a combination of wave plates and polarizers. However, this method cannot be extended to higher-order Poincaré spheres and complex polarization patterns produced by coherent superpositions of vector vortex (VV) beams. We demonstrate the visualization of complex polarization patterns by imprinting them onto a solid surface in the form of periodic nano-gratings oriented parallel to the local structure of the electric field of light. We design unconventional surface structures by controlling the superposition of VV beams. Our method is of potential interest to the production of sub-wavelength nano-structures.

Endoscopic pericranial flap design for the restoration of nasal mid-vault lining defects.

Despite progress made in nasal reconstruction, the restoration of a large defect, including the whole septum and mid-nasal vault structures, remains a challenge. The pericranial flap (PCF) is used widely for the reconstruction of anterior cranial fossa defects. This article presents a surgical technique for nasal lining restoration with an endoscopic PCF design. This technique was used in patients with huge intranasal tumours. Two patients with nasal eosinophilic angiocentric fibrosis were treated. The structural involvement was similar in each case. The tumour was resected completely by combined endoscopic and external methods through an open rhinoplasty approach. The resulting defect included the whole nasal septum, bilateral upper lateral cartilage, and the entire mid-nasal vault mucosal lining. Reconstruction was achieved by endoscopic PCF design for internal lining reconstruction and rib cartilage for framework repair. The first patient was followed up for 18months and the second for 8months. No infection occurred in the postoperative period. Framework stability and texture were good, and both nasal shapes were acceptable. In conclusion, this endoscopic PCF approach for restoring the internal nasal lining appears to be a good choice in selected cases.

Protective effects of Smyrnium cordifolium boiss essential oil on pentylenetetrazol-induced seizures in mice: involvement of benzodiazepine and opioid antagonists.

Smyrnium cordifolium as a wild plant is used in traditional medicine in Iran for the treatment of anxiety and insomnia. The anticonvulsant effect of this plant has not been studied to date, therefore this study aimed to evaluate the anticonvulsant effects of its essential oil and curzerene on seizure. Essential oil of the Smyrnium cordifolium plant was prepared by the hydro-distillation method. Gas chromatography and gas chromatography-mass spectroscopy analysis of the essential oil revealed its main components. Anticonvulsant effects of Smyrnium cordifolium essential oil (SCEO) and curzerene were examined on mice using the pentylentetrazole model (PTZ). Flumazenil (2 mg/kg, i.p) and naloxone (5 mg/kg, i.p) were injected into the relevant groups of mice to realize the anticonvulsant mechanism of SCEO and curzerene, respectively. The main identified components of the plant were curzerene (65.26%), δ-Cadinene (14.39%) and γ-elemene (5.15%), which comprised approximately 85.28% of SCEO. The ED50 values of SCEO and curzerene in the PTZ model were 223±15 and 0.25±0.09 mg/kg, respectively. Curzerene at the dosage of 0.4 mg/kg prolonged the onset time of seizure and decreased the duration of seizure among treated group compared to the saline group. At the dosage of 0.4 mg/kg, seizure and mortality protection rates for the treated group were 100%. Flumazenil and naloxone could suppress the anticonvulsant effects of SCEO and curzerene. It seems that SCEO and curzerene are useful for the treatment of absence seizure and this effect may be related to their effects on GABAergic and opioid systems.

Q-plates as higher order polarization controllers for orbital angular momentum modes of fiber.

We demonstrate that a |q|=1/2 plate, in conjunction with appropriate polarization optics, can selectively and switchably excite all linear combinations of the first radial mode order |l|=1 orbital angular momentum (OAM) fiber modes. This enables full mapping of free-space polarization states onto fiber vector modes, including the radially (TM) and azimuthally polarized (TE) modes. The setup requires few optical components and can yield mode purities as high as ∼30 dB. Additionally, just as a conventional fiber polarization controller creates arbitrary elliptical polarization states to counteract fiber birefringence and yield desired polarizations at the output of a single-mode fiber, q-plates disentangle degenerate state mixing effects between fiber OAM states to yield pure states, even after long-length fiber propagation. We thus demonstrate the ability to switch dynamically, potentially at ∼GHz rates, between OAM modes, or create desired linear combinations of them. We envision applications in fiber-based lasers employing vector or OAM mode outputs, as well as communications networking schemes exploiting spatial modes for higher dimensional encoding.

Assessing the genetic relationships of Curcuma alismatifolia varieties using simple sequence repeat markers.

The genus Curcuma is a member of the ginger family (Zingiberaceae) that has recently become popular for use as flowering pot plants, both indoors and as patio and landscape plants. We used PCR-based molecular markers (SSRs) to elucidate genetic variation and relationships between five varieties of Curcuma (Curcuma alismatifolia) cultivated in Malaysia. Of the primers tested, 8 (of 17) SSR primers were selected for their reproducibility and high rates of polymorphism. The number of presumed alleles revealed by the SSR analysis ranged from two to six alleles, with a mean value of 3.25 alleles per locus. The values of HO and HE ranged from 0 to 0.8 (mean value of 0.2) and 0.1837 to 0.7755 (mean value of 0.5102), respectively. Eight SSR primers yielded 26 total amplified fragments and revealed high rates of polymorphism among the varieties studied. The polymorphic information content varied from 0.26 to 0.73. Dice's similarity coefficient was calculated for all pairwise comparisons and used to construct an unweighted pair group method with arithmetic average (UPGMA) dendrogram. Similarity coefficient values from 0.2105 to 0.6667 (with an average of 0.4386) were found among the five varieties examined. A cluster analysis of data using a UPGMA algorithm divided the five varieties/hybrids into 2 groups.

Genetic relationship among Labisia pumila (Myrsinaceae) species based on ISSR-PCR.

The genus Labisia (Myrsinaceae) is a popular medicinal plant in Malaysia. We examined the genetic relationship among three varieties of L. pumila var. pumila, L. pumila var. alata, L. pumila var. lanceolata and Labisia paucifolia using an ISSR assay. Fifty-eight primers were tested, among which 18 gave reliable polymorphic banding patterns; these yielded 264 polymorphic markers. A similarity matrix was used to construct a dendrogram, and a principal component plot was developed to examine genetic relationships among varieties. Jaccard's similarity coefficient among species ranged from 0.09 to 0.14. At a similarity of 0.117%, species were divided into two main clusters. The mean value of the observed number of alleles, the effective number of alleles, mean Nei's gene diversity, and Shannon's information index were 1.98, 1.64, 0.38, and 0.57, respectively.

Polarization control of single photon quantum orbital angular momentum states.

The orbital angular momentum of photons, being defined in an infinite-dimensional discrete Hilbert space, offers a promising resource for high-dimensional quantum information protocols in quantum optics. The biggest obstacle to its wider use is presently represented by the limited set of tools available for its control and manipulation. Here, we introduce and test experimentally a series of simple optical schemes for the coherent transfer of quantum information from the polarization to the orbital angular momentum of single photons and vice versa. All our schemes exploit a newly developed optical device, the so-called "q-plate", which enables the manipulation of the photon orbital angular momentum driven by the polarization degree of freedom. By stacking several q-plates in a suitable sequence, one can also have access to higher-order angular momentum subspaces. In particular, we demonstrate the control of the orbital angular momentum m degree of freedom within the subspaces of |m| = 2h and |m| = 4h per photon.

[Rare abdominal and peritoneal localizations of hydatid cysts. Report on two cases (author's transl)]. / Localisations abdominales et péritonéales exceptionnelles du kyste hydatique. A propos de deux cas.

Rarely observed isolated peritoneal hydatid cysts, without initial hepatic lesions or later development in other viscera, were detected in two patients. The diagnosis of hydatidosis confined to the mesocolon was established pre-operatively in the first case, enabling mebendazole treatment to be instituted. In the second case, however, pre-operative diagnosis was not possible, demonstrating the sometimes misleading appearances found in this affection. Aetiopathogenic and diagnostic features are briefly discussed. Therapy raises problems, and though good results have recently been obtained with benzimidazole derivatives, surgical excision in currently the only curative treatment available. Medical treatment (with benzimidazole derivatives) is indicated only in cases with multiple cysts inaccessible to surgery, or a complementary therapy to facilitate excision, reduce risks of propagation during operation, and prevent recurrences.