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Background/Objectives: Epiphora, or excessive tearing, is a common symptom often attributed to benign conditions such as dry eye or nasolacrimal duct obstruction. However, it can also be an early indicator of lacrimal sac tumors, which are frequently misdiagnosed or diagnosed late due to their subtle presentation. This study aims to identify the clinical features that contribute to delays and misdiagnoses of lacrimal sac tumors in patients presenting with epiphora, with the goal of improving early detection and treatment outcomes. Methods: This retrospective study reviewed medical records from Taipei Veterans General Hospital between 2007 and 2023, focusing on patients who presented with epiphora and were later diagnosed with pathologically confirmed lacrimal sac tumors. Inclusion criteria were limited to cases that were initially misdiagnosed or had a delayed diagnosis, with imaging and clinical evaluations confirming tumor-related tear drainage obstruction. Patients with non-tumor causes of epiphora were excluded. Results: Eleven cases of lacrimal sac tumors were identified, including two benign and nine malignant tumors. The average duration from symptom onset to diagnosis was 22.4 months. Common symptoms included epiphora (100%), discharge (54.5%), and hemolacria (18.2%). Subtle clinical signs, such as asymmetry in the medial canthal region and non-tender swelling, were frequently noted. Despite receiving appropriate surgical and adjuvant treatments, the impact of delayed diagnosis was significant. Two patients succumbed to tumor-related disease; one developed lung metastasis 12 years after diagnosis, and another experienced recurrence during a six-year follow-up after undergoing extensive exenteration, adjuvant chemotherapy, and radiotherapy. Conclusions: Lacrimal sac tumors can present insidiously with symptoms often mistaken for benign conditions, leading to significant diagnostic delays. Thorough history taking, meticulous physical examination, and timely imaging are crucial for early detection. Increased clinician awareness and a high index of suspicion for lacrimal sac tumors in patients with atypical epiphora are essential to improve prognosis and reduce the risk of severe outcomes. [ABSTRACT FROM AUTHOR]

Recurrence of pressure ulcers following reconstructive surgery occurs frequently, causing a significant burden on the patient and the public health care system. We assessed risk factors for the recurrence of pressure ulcers based on the experience of a single surgeon at our medical centre. We retrospectively analysed patients admitted to our medical centre with stage III and IV pressure ulcers who underwent reconstructive surgery. The hospital database was searched for patients diagnosed with pressure ulcers who underwent reconstructive surgery. Patient characteristics analysed included age, sex, cause and location of defect, comorbidities, lesion size, wound reconstruction methods, operation time, debridement times, duration of hospital stay, and wound complications. Recurrence and mortality rates were retrospectively examined. One hundred and eighty‐nine patients were enrolled, and 166 patients with 176 pressure ulcers met our inclusion criteria. All 14 recurrences (7.95%) were followed for at least 1 year. Logistic regression analysis indicated that recurrence was associated with albumin levels (P = 0.001) and wound size (P = 0.043); however, no association was found for body mass index, bacterial profile, comorbidities, localisation, previous surgery, operation time, or time to admission for reconstruction. In conclusion, higher albumin levels were associated with lower recurrence rates in patients who underwent reconstructive surgery. [ABSTRACT FROM AUTHOR]

Twelve- to sixteen-month-old (G2019S) LRRK2 transgenic mice prepared by us displayed progressive neuronal death of substantia nigra pars compacta (SNpc) dopaminergic cells. In the present study, we hypothesized that prior to a late-phase death of SNpc dopaminergic neurons, (G2019S) LRRK2 also causes an early-phase neuronal dysfunction of SNpc dopaminergic cells in the (G2019S) LRRK2 mouse. Eight to nine-month-old (G2019S) LRRK2 transgenic mice exhibited the symptom of hypoactivity in the absence of the degeneration of SNpc dopaminergic neurons or nigrostriatal dopaminergic terminals. Whole-cell current-clamp recordings of SNpc dopaminergic cells in brain slices demonstrated a significant decrease in spontaneous firing frequency of SNpc dopaminergic neurons of 8-month-old (G2019S) LRRK2 mice. Carbon fiber electrode amperometry recording using striatal slices showed that (G2019S) LRRK2 transgenic mice at the age of 8 to 9 months display an impaired evoked dopamine release in the dorsolateral striatum. Normal nigrostriatal dopaminergic transmission is required for the induction of long-term synaptic plasticity expressed at corticostriatal glutamatergic synapses of striatal medium spiny neurons. Whole-cell voltage-clamp recordings showed that in contrast to medium spiny neurons of 8 to 9-month-old wild-type mice, high-frequency stimulation of corticostriatal afferents failed to induce long-term depression (LTD) of corticostriatal EPSCs in medium spiny neurons of (G2019S) LRRK2 mice at the same age. Our study provides the evidence that mutant (G2019S) LRRK2 causes early-phase dysfunctions of SNpc dopaminergic neurons, including a decrease in spontaneous firing rate and a reduction in evoked dopamine release, and impairment of corticostriatal LTD in the (G2019S) LRRK2 transgenic mouse.

This study investigates the effects of asymmetric coupling strength on nonlinear dynamics of two mutually long-delay-coupled semiconductor lasers through both experimental and numerical efforts. Dynamical maps and spectral features of dynamical states are analyzed as a function of the coupling strength and detuning frequency for a fixed coupling delay time. Symmetry in the coupling strength of the two lasers, in general, symmetrizes their dynamical behaviors and the corresponding spectral features. Slight to moderate asymmetry in the coupling strength moderately changes their dynamical behaviors from the ones when the coupling strength is symmetric, but does not break the symmetry of their dynamical behaviors and the corresponding spectral features. High asymmetry in the coupling strength not only strongly changes their dynamical behaviors from the ones when the coupling strength is symmetric, but also breaks the symmetry of their dynamical behaviors and the corresponding spectral features. Evolution of the dynamical behaviors from symmetry to asymmetry between the two lasers is identified. Experimental observations and numerical predictions agree not only qualitatively to a high extent but also quantitatively to a moderate extent. [ABSTRACT FROM AUTHOR]

This paper presents a novel, compact, low-insertion-loss, sharp-rejection, wideband microstrip bandpass filter. The filter is based on a ring resonator with direct-connected orthogonal feed lines, and uses two stepped-impedance open stubs to construct a wideband passband with two sharp stopbands. The unit cell of the ring resonators is easily cascaded and also has the feature of a compact structure. The filter is designed to reduce interference in full-duplex systems for satellite communications. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 45: 312–315, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20807 [ABSTRACT FROM AUTHOR]

This letter presents the design and implementation of a 24-/60-GHz millimeter-wave dual-band on-chip bandpass filter using a O.18-~im standard CMOS process. The concept of quarter-wavelength stepped-impedance resonator (A/4 SIR) is utilized to realize stopband characteristics at desired frequencies and reduce the chip size. The structure of the open-circuited dual-behavior resonators (OC-DBR5) produces one passband with two transmission zeros on either side. The size of the designed filter is 1.030 x 0.590 mm2. [ABSTRACT FROM AUTHOR]

This letter presents the design and implementation of a 70 GHz millimeter-wave compact folded loop dual-mode on-chip bandpass filter (BPF) using a 0.18 mum standard CMOS process. A compact BPF, consisting of such a planar ring resonator structure having dual transmission zeros was fabricated and designed. The size of the designed filter is 650 X 670 mum2. Calculated circuit model, EM simulated and measured results of the proposed filter operating at 70 GHz are shown in a good agreement and have good performance. The filter has a 3-dB bandwidth of about 18 GHz at the center frequency of 70 GHz. The measured insertion loss of the passband is about 3.6 dB and the return loss is better than 10 dB within the passband. [ABSTRACT FROM PUBLISHER]

This letter presents the design and implementation of a 60-GHz millimeter-wave RF-integrated-circuit-on-chip bandpass filter using a 0.18-µm standard CMOS process. A planar ring resonator structure with dual-transmission zeros was adopted in the design of this CMOS filter. The die size of the chip is 1.148 × 1.49 mm². The investigations of sensitivity to the insertion loss and the passband bandwidth for different perturbation stub sizes are also studied. The filter has a 3-dB bandwidth of about 12 GHz at the center frequency of 64 GHz. The measured insertion loss of the passband is about 49 dB, and the return loss is better than 10 dB within the passband. [ABSTRACT FROM AUTHOR]

A new dual-band planar filter has been proposed. It is shown that the two transmission bands can be excited and designed using proposed resonators which combine different sizes of open-loop resonators. The main resonators control the low-band resonant frequency and the sub resonators control the high-band resonant frequency. With dual-feeding structures added, the performances of the filter such as frequency selectivity and insertion loss are much improved. The embedded resonators structure can further miniaturize the dimensions of the overall structure. The proposed dual-band filter will find applications in wireless communication circuits [ABSTRACT FROM PUBLISHER]

A new type of novel low loss dual-band microstrip filters using folded open-loop ring resonators (OLRRs) is presented in this letter. Both magnetic and electric coupling structures are implemented to provide high performance passband response. The first passband and second passband of the designed dual-band filter can be easily and accurately shifted to a desired frequency band by adjusting the physical dimensions of OLRRs. Finally, the 2.4-GHz/5.7-GHz and 2.4-GHz/5.2-GHz dual-band filters are illustrated and measured in this letter. [ABSTRACT FROM PUBLISHER]

A novel miniaturized microstrip-line filter using a pair of interlocking resonators is proposed. To reduce the size dimensions and suppress the spurious responses simultaneously, a stepped-impedance structure is integrated into this new proposed filter. The cross-coupling effect can be created in this designed filter. Furthermore, the filter has two transmission zeros on both sides of the passband. The full-wave simulator IE3D is used to design and simulate the interlocking resonators bandpass filter. The design is been verified by the experiment results. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 261–263, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21141 [ABSTRACT FROM AUTHOR]

Compared with the conventional log-periodic balun, the design of a symmetric log-periodic balun can provide better performance over the entire designed band. A novel ultra-wideband (UWB) balun with 3–6 GHz passband is demonstrated for UWB applications. The problems of fabrication and measurement of the conventional log-periodic balun operated at higher frequency problems can be further improved. The magnitude and phase difference between two output ports are kept balancing at higher band edge portion. The measured amplitude imbalance is about ±1.1 dB with a corresponding phase difference about ±4°. The bandwidth of the balun is around 70%. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 947–948, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23264 [ABSTRACT FROM AUTHOR]

Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.